You searched for +publisher:"University of Manchester" +contributor:("Kinloch, Ian").
Showing records 1 – 30 of
35 total matches.
◁ [1] [2] ▶
University of Manchester
1.
Aranga Raju, Arun Prakash.
PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:296571 
► Graphene, a single layer of graphite, owing to its excellent mechanical, electrical, and thermal properties, has evolved as an exceptional nanomaterial in the past decade.…
(more)
▼ Graphene, a single layer of graphite, owing to its
excellent mechanical, electrical, and thermal properties, has
evolved as an exceptional nanomaterial in the past decade. It holds
great promise in developing various novel applications from
biomedical to structural composites. However, several challenges
remain in realising the great potential of this material; one being
the bulk scale production of graphene. This thesis has been
concerned with production of pristine few-layer graphene (FLG)
using liquid phase exfoliation (LPE) of graphite in various solvent
media and exploring the applications of graphene-based composite
coatings as optical Raman-strain sensors.LPE of natural graphite
using bath sonication was used to produce highly stable pristine
FLG in 1-methyl-2-pyrrolidinone (NMP) and N,N-dimethylformamide
(DMF). Atomic force microscope (AFM) was used to analyse the
exfoliation efficiency and lateral dimensions, while Raman
spectroscopy provided an insight about the quality of the graphene
flakes. Moreover, the potential for dynamic light scattering (DLS)
as an efficient in situ characterisation technique for estimating
the lateral dimensions of graphene flakes in dispersions was
demonstrated.LPE was also employed to explore various routes to
produce pristine graphene in aqueous media which can be used for
toxicity studies. Aqueous dispersions were prepared by a solvent
exchange method of graphene originally in organic solvents (NMP and
DMF) using dialysis, achieving 0.1 v/v% organic solvent levels.
Pristine aqueous graphene dispersions were also prepared by
directly exfoliating graphite in biocompatible surfactant (TDOC-
Sodium taurodeoxycholate) and biomolecules (Phosphatidylcholine and
human serum albumin) solutions. Cell culture studies by
collaborators revealed that solvent-exchanged and TDOC-exfoliated
pristine FLG displayed minimal toxicity and albumin-exfoliated FLG
hardly any cytotoxicity, whereas phosphatidylcholine-exfoliated FLG
was cytotoxic.Raman spectroscopy is a well-established technique
used to study the local deformation of carbon-based composites by
following the shift rates of the Raman 2D band with strain. Raman
active strain coatings were produced from epoxy composites made
with the FLG produced by LPE in organic solvents and by
electrochemical exfoliation method. The deformation experiments on
these coatings revealed little or no strain sensitivity, due to
several factors such as length of flakes, processing history,
graphene loading, defects in graphene and alignment of flakes
within the composites. As an alternative, composite coatings made
from chemical vapour deposition (CVD) graphene were investigated.
Excellent strain sensitivity was observed upon various cyclic
deformational sequences and Raman mapping over 100 × 100 µm area.
In comparison to the commercially available wide area strain
sensors, CVD graphene composite coatings with a calculated absolute
accuracy of ~ ± 0.01 % strain and absolute resolution of ~ 27
microstrains show promise for wide area Raman-based strains
sensors.
Advisors/Committee Members: Kinloch, Ian.
Subjects/Keywords: Graphene; Liquid Phase Exfoliation; Raman Spectroscopy; Strain Sensors; Composite Coatings
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Aranga Raju, A. P. (2016). PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:296571
Chicago Manual of Style (16th Edition):
Aranga Raju, Arun Prakash. “PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:296571.
MLA Handbook (7th Edition):
Aranga Raju, Arun Prakash. “PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES.” 2016. Web. 20 Jun 2019.
Vancouver:
Aranga Raju AP. PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:296571.
Council of Science Editors:
Aranga Raju AP. PRODUCTION AND APPLICATIONS OF GRAPHENE AND ITS
COMPOSITES. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:296571
University of Manchester
2.
Lomax, Deborah.
Electrowetting and Electrodeposition on Graphitic
Surfaces.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305768
► Graphite and graphene electrodes are used to study two electrochemical processes: the decoration of these electrodes with Au metallic nanoparticles through the use of electrodeposition,…
(more)
▼ Graphite and graphene electrodes are used to study
two electrochemical processes: the decoration of these electrodes
with Au metallic nanoparticles through the use of
electrodeposition, and electrowetting, the potential-dependent
change in hydrophobicity of a surface. Electrodeposition provides a
useful route to electrode functionalisation, in particular to
combine the enhanced properties of metallic nanoparticles with the
advantageous features of carbon materials. A combination of cyclic
voltammetry, chronoamperometry, and both ex situ and in situ atomic
force microscopy are used to deduce the mechanism of Au
electrodeposition on graphite and graphene. Notably, the mechanism
of Au nanoparticle formation cannot be deduced from simple
voltammetry alone, and the spontaneous formation of Au within the
timescale of the electrodeposition experiment is confirmed.
Electrowetting is a uniquely responsive method to manipulate the
wetting properties of an electrode. However, a dielectric coating
is commonly required to protect the surface from electrolysis,
which in turn further increases the potentials needed to perform
electrowetting. In contrast to this, here it is shown that bare
graphite and graphene electrodes support electrowetting without the
disadvantages of a dielectric coating, allowing an unprecedented
combination of performance and efficiency. Furthermore, the ideal
behaviour this system demonstrates is implemented as a platform to
study electrowetting itself. The influence of electrolyte
composition, surface defects and electrode-blocking dielectric-like
films are investigated to determine the factors that impede
electrowetting, a key step to understanding the phenomenon that is
normally hindered by the use of the dielectric.
none
none
Advisors/Committee Members: KINLOCH, IAN IA, Dryfe, Robert, Kinloch, Ian.
Subjects/Keywords: electrodeposition; electrowetting; graphene; graphite; gold; contact angle
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lomax, D. (2016). Electrowetting and Electrodeposition on Graphitic
Surfaces. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305768
Chicago Manual of Style (16th Edition):
Lomax, Deborah. “Electrowetting and Electrodeposition on Graphitic
Surfaces.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305768.
MLA Handbook (7th Edition):
Lomax, Deborah. “Electrowetting and Electrodeposition on Graphitic
Surfaces.” 2016. Web. 20 Jun 2019.
Vancouver:
Lomax D. Electrowetting and Electrodeposition on Graphitic
Surfaces. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305768.
Council of Science Editors:
Lomax D. Electrowetting and Electrodeposition on Graphitic
Surfaces. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305768
University of Manchester
3.
Woolfson, Robert Jack.
Spins in Rings: New Chemistry and Physics with Molecular
Wheels.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305896
► This thesis explores the synthesis and characterisation of a range of molecular wheels containing unpaired electron spins. These molecular spin systems are of considerable interest,…
(more)
▼ This thesis explores the synthesis and
characterisation of a range of molecular wheels containing unpaired
electron spins. These molecular spin systems are of considerable
interest, both for the insight they provide into the physics of
such systems and for their potential as quantum bits (“qubits”) in
a quantum information processing device. In particular, this thesis
explores using these wheels to meet criteria 1 and 5 of the
DiVincenzo criteria.The synthesis of a novel homometallic and
nonametallic ring of CrIII ions is introduced, along with extensive
physical characterisation. Inelastic Neutron Scattering
measurements suggest that the molecule has an almost degenerate S =
1/2 ground state with only 0.1 meV separation, making this ring a
near perfect example of a Type I frustrated spin system.Chemical
modification of the heterometallic {Cr7M} family of wheels with
both hard and soft Lewis base functionality is also explored. Using
a triphenylphosphine derivative, the coordination chemistry of a
highly sterically hindered mono-substituted triphenylphosphine
derivative with gold is explored, yielding new arrangements of the
wheels. Changes in the electronic and steric properties of the
system are studied by a combination of 31P NMR spectroscopy and DFT
modelling, revealing dramatic changes in the phosphorus donor
properties.The effect of this ligand substitution on the anisotropy
tensor of CoII contained in a heterometallic {Cr7Co} ring is
explored using variable temperature 1H NMR spectroscopy. Using a
combination of the experimentally observed 1H NMR dipolar shifts
and computational modelling, a significant change in the anisotropy
tensor of the cobalt is found.Finally, as part of a g-engineering
approach to qubit design the chemistry of the octametallic {Cr7Ni}
ring functionalised with triphenylphosphine oxide is introduced.
Initial efforts towards developing a hybrid {Cr7Ni}2Ln (Ln = Gd,
Eu) qubit system, along with characterisation by EPR and
luminescence spectroscopy, suggest that this may be a route to
developing a qubit with the capacity for optical control of the
communication.
N/A
N/A
Advisors/Committee Members: KINLOCH, IAN IA, Winpenny, Richard, Kinloch, Ian.
Subjects/Keywords: Molecular Magnetism; Chemistry; Nanoscience; Quantum Computing
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Woolfson, R. J. (2016). Spins in Rings: New Chemistry and Physics with Molecular
Wheels. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305896
Chicago Manual of Style (16th Edition):
Woolfson, Robert Jack. “Spins in Rings: New Chemistry and Physics with Molecular
Wheels.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305896.
MLA Handbook (7th Edition):
Woolfson, Robert Jack. “Spins in Rings: New Chemistry and Physics with Molecular
Wheels.” 2016. Web. 20 Jun 2019.
Vancouver:
Woolfson RJ. Spins in Rings: New Chemistry and Physics with Molecular
Wheels. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305896.
Council of Science Editors:
Woolfson RJ. Spins in Rings: New Chemistry and Physics with Molecular
Wheels. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305896
University of Manchester
4.
Bin Junid, Ramli.
Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305819
► This thesis reports the effects of incorporating graphite nanoplatelets (GNPs) to epoxy-carbon fibre (CF) laminates to produce multiscale composites. A grade of epoxy resin typical…
(more)
▼ This thesis reports the effects of incorporating
graphite nanoplatelets (GNPs) to epoxy-carbon fibre (CF) laminates
to produce multiscale composites. A grade of epoxy resin typical
for the application in aerospace engineering,
triglycidyl-p-aminophenol (TGPAP), was used in this work cured with
4,4’-diaminodiphenyl sulfone (DDS). To improve the processability
of TGPAP, a diluent, the diglycidyl ether of bisphenol F (DGEBF),
was added to formulations. Compositions of TGPAP/DGEBF/DDS were
optimised using response surface methodology (RSM) with the target
response being to obtain high glass transition temperature (Tg) and
low resin viscosity. From RSM, the optimum values were obtained at
55.6 wt. % of DGEBF and a stoichiometric ratio of 0.60. Before
addition into epoxy, GNPs were treated either covalently using
3-aminopropyltriethoxysilane (APTS) or non-covalently using a
commercial surfactant, Triton X-100 (abbreviated as A-GNPs and
T-GNPs, respectively). After treatment, XPS analysis showed a new
peak at 100 eV for A-GNPs indicating silicon and the C/O ratio
increased from 11.0 to 26.2 for T-GNPs relative to unmodified GNPs
(U-GNPs), suggesting attachment of the modifier molecules had
occurred. Nanocomposites (NCs) were prepared by incorporate GNPs
into epoxy using mechanical mixing. Rheological percolation
threshold of GNP-epoxy suspensions were determined using
oscillatory-shear rheometry as 3.9 wt. % for AR-GNPs, 3.6 wt. % for
U-GNPs, 3.2 wt. % for A-GNPs and 3.5 wt. % for T-GNPs, suggesting
surface treatment improved dispersion. At 4 wt. % of GNPs, flexural
strain of NCs was decreased relative to neat epoxy by 46% for
AR-GNPs, 48.6% for U-GNPs, 4.6% for A-GNPs and 30.8% for T-GNPs but
flexural moduli showed small increases of 6.1-7.4%. Fracture
toughness (K1C) also improved. For example, the K1C increased from
0.80 ± 0.04 MPa.m1/2 for neat epoxy to 1.32 ± 0.01 MPa.m1/2 for NCs
containing 6 wt. % of U-GNPs possibly due to the branching of
cracks resulting from the embedded GNPs. Due to their mechanical
performance, A-GNPs were used to fabricate epoxy/CF/A-GNPs
multiscale composites. Multiscale composites showed inferior
properties relative to a comparable conventional composite in
flexural testing, interlaminar shear strength (ILSS) and
interlaminar fracture toughness mode II (G11C) due to weaker
bonding at the matrix-CF interface. However, multiscale composites
showed ~40% higher capability than conventional composite to absorb
energy during impact due to greater interfaces formed by the
inclusion of A-GNPs into the system.
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
Subjects/Keywords: Graphene nanoplatelets; Graphite nanoplaletets; Epoxy/CF Mutliscale composites; Eppoxy/GNPs nanocomposite
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bin Junid, R. (2016). Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305819
Chicago Manual of Style (16th Edition):
Bin Junid, Ramli. “Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305819.
MLA Handbook (7th Edition):
Bin Junid, Ramli. “Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices.” 2016. Web. 20 Jun 2019.
Vancouver:
Bin Junid R. Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305819.
Council of Science Editors:
Bin Junid R. Multiscale Carbon Fibre Composites with Epoxy-Graphite
Nanoplatelet Matrices. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:305819
University of Manchester
5.
Zou, Yuqin.
INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE.
Degree: 2017, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309068
► In this thesis, the synthesis and characterization of nitrogen-doped graphene (NG) and NG-Co3O4 composites are described. Moreover, the effect of airborne contamination and nitrogen doping…
(more)
▼ In this thesis, the synthesis and characterization
of nitrogen-doped graphene (NG) and NG-Co3O4 composites are
described. Moreover, the effect of airborne contamination and
nitrogen doping on the capacitance of graphene was
investigated.Firstly, nitrogen-doped thermally expanded graphene
oxide (NtGO) was prepared by a facile thermal expansion and
hydrothermal doping process. The thermal expansion process plays a
vital role in improving the electrochemical performance of N-doped
graphene by preventing its aggregation and improving its
conductivity. The specific capacitance of NtGO is 270 F g−1 at a
discharge current density of 1 A g−1 and the capacitance retention
is 97 % after 2000 cycles at this current density. Secondly, a
hierarchical electrode structure, consisting of cobalt oxide and
nitrogen-doped graphene foam (NGF), has been fabricated with the
aim of achieving enhanced charge storage performance. The Co3O4/NGF
electrode shows an enhanced charge-storage performance, attributed
to the 3D hierarchical structure and the synergistic effect of
Co3O4 and NGF. The present study shows that specific capacitances
as high as 451 F g−1 can be obtained, indicating that
high-performance electrochemical capacitors can be made using
electrode materials with advanced structures. Thirdly, a study of
the differences between the capacitance of freshly exfoliated
highly ordered pyrolytic graphite (HOPG, sample denoted FEG), HOPG
aged in air (denoted AAG) and aged in an inert atmosphere
(hereafter IAG) is presented in this work. Electrochemical
impedance spectroscopy shows the FEG possesses a higher intrinsic
capacitance (6.0 µF cm−2 at the potential of minimum capacitance)
than AAG (4.3 µF cm−2) and IAG (4.7 µF cm−2). This change in
capacitance is correlated with other physical changes of the
sample, and attributed to contamination due to airborne
hydrocarbons.Finally, the effect of N-doping of graphene prepared
by chemical vapour deposition is investigated. The differential
capacitance of PG and NG was measured by a
microinjection-micromanipulator system. The quantum capacitance of
PG and NG was calculated and discussed. The increase in
differential capacitance with nitrogen-doping and the growth of the
quantum capacitance of NG suggest that the increased capacitance of
many electrodes of electrochemical capacitors is primarily due to
the modification of the electronic structure of the graphene by the
N dopant.
none
none
Advisors/Committee Members: KINLOCH, IAN IA, Dryfe, Robert, Kinloch, Ian.
Subjects/Keywords: graphene; supercapacitor; electrochemical properties
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zou, Y. (2017). INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309068
Chicago Manual of Style (16th Edition):
Zou, Yuqin. “INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE.” 2017. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309068.
MLA Handbook (7th Edition):
Zou, Yuqin. “INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE.” 2017. Web. 20 Jun 2019.
Vancouver:
Zou Y. INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309068.
Council of Science Editors:
Zou Y. INVESTIGATION OF THE ELECTROCHEMICAL PROPERTIES OF
GRAPHENE. [Doctoral Dissertation]. University of Manchester; 2017. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:309068
University of Manchester
6.
Mohd Halit, Muhammad Khairulanwar bin.
Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:314143
► Graphene Nanoplatelets (GNP) was incorporated into polyamide 6 (PA6) matrix by melt compounding method and the enhancements in the properties of the nanocomposites were studied.…
(more)
▼ Graphene Nanoplatelets (GNP) was incorporated into
polyamide 6 (PA6) matrix by melt compounding method and the
enhancements in the properties of the nanocomposites were studied.
Response Surface Methodology (RSM) was employed to assist in the
study of processing conditions in melt compounding. RSM analysis
revealed that the GNP concentrations to be the most significant
term to affect the tensile modulus and crystallinity followed by
the screw speed whereas the residence time was found to be
non-significant. GNP with 5 μm (G5) and 25 μm (G25) were used in
the GNP aspect ratio study. The average flake size of G5 and G25 to
was measured to be 5.07 μm and 22.0 μm, respectively with the G5
distributed narrowly whereas the G25 exhibit broad distribution.
TGA analysis shown that HT25 is more thermally stable compared to
G25 due to some remnants lost during thermal treatment and this was
confirmed by EDX and CHNS analysis. XRD profiles of the PA6-G-NC
illustrate typical peaks of PA6 crystals phase as well as pure
graphite characteristic peak. PA6-G25-NC observed to exhibit
slightly higher peak intensity compared to PA6-G5-NC suggesting
more formation of PA6 crystals. Similar improvement was observed on
PA6-HT25-NC compared to PA6-G25-NC indicating more formation of PA6
crystals due improved dispersion of HT25. DSC on PA6-G25-NC showed
higher cooling temperature and crystallinity compared to PA6-G5-NC
due to larger surface area of the G25. Similarly, PA6-HT25 showed
better improvement in crystallinity over PA6-G25-NC due to increase
nucleation sites by the HT25. The thermal conductivity of
PA6-G25-NC is slightly higher than the thermal conductivity of
PA6-G5-NC but not significant considering the G25 is 5 times larger
than G5. Instead, no significant difference was observed between
PA6-HT25-NC and PA6-G25-NC. Addition of GNP increased the thermal
stability of the PA6-G-NC systems under both nitrogen and air
atmospheres regardless of the GNP aspect ratio. The viscoelastic
properties showed insignificant difference between PA6-G5-NC and
PA6-G25-NC. The inefficient improvement by G25 might be due to
agglomeration formed during processing. The storage modulus and tan
δ of PA6-HT25-NC decreased but the Tg significantly improved
compared to PA6-G25-NC. This was assumed to be because of improved
dispersion of HT25 but reduced interfacial interaction after the
heat treatment. The shear storage modulus, G’ and complex
viscosity, |η*| were observed to increase with increasing GNP
content with more pronounced improvement seen on PA6-G25-NC
compared to PA6-G5-NC. However, no network percolation threshold
was observed until 20 wt.% of GNP. The poor interfacial interaction
of HT25 resulted in lower G’ and |η*| compared to G25. Tensile
test results showed typical improvement with PA6-G25-NC having
higher tensile modulus compared to PA6-G5-NC. Further enhancement
was obtained with PA6-HT25-NC suggesting improved dispersion and
volume of constrained chains mobility despite the poor surface
interaction. Comparison with Halphin-Tsai…
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
Subjects/Keywords: Graphene nanocomposites; Polymer composites; Polyamide 6; Graphene nanoplatelets
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mohd Halit, M. K. b. (2018). Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:314143
Chicago Manual of Style (16th Edition):
Mohd Halit, Muhammad Khairulanwar bin. “Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:314143.
MLA Handbook (7th Edition):
Mohd Halit, Muhammad Khairulanwar bin. “Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites.” 2018. Web. 20 Jun 2019.
Vancouver:
Mohd Halit MKb. Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:314143.
Council of Science Editors:
Mohd Halit MKb. Processing, Structure and Properties of Polyamide
6/Graphene Nanoplatelets Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:314143
University of Manchester
7.
Srivastava, Deepanshu.
Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303607
► Oxide ceramics have been increasingly researched for high temperature thermoelectric (TE) applications. SrTiO3 based materials are promising candidates due to its chemical and thermal stability.…
(more)
▼ Oxide ceramics have been increasingly researched
for high temperature thermoelectric (TE) applications. SrTiO3 based
materials are promising candidates due to its chemical and thermal
stability. In this study, oxide ceramics of composition
(1-x)SrTiO3-(x)La1/3NbO3 (0 ≤ x ≤ 0.3) were prepared by single-step
solid state sintering in Ar/5%H2 at 1700 K. The density of all the
samples prepared was above 90%. All the samples were predominantly
single-phase compositions crystallised with a cubic structure in Pm
̅3m space group.The impact of oxygen deficiency, A-site vacancies
and mixed oxidation states of Ti3+/Nb4+ on electrical and thermal
transport properties was assessed. Optimum TE properties were
obtained for x=0.2 (Sr0.8La0.067Ti0.8Nb0.2O(3-δ) = L2), which has
13.4% A-site vacancies. The ZT values improved from 0.2 to 0.27 at
1000 K, with an increase in sintering time from 8 hours to 48
hours, due to increased carrier concentration. Complex interplay of
oxygen vacancies and excess donor substitution on A/B-sites of L2
(substituting 5-10% Sr/Ti with La/Nb) exhibited 35% improvement in
ZT values, whilst maintaining the A-site vacancies and core-shell
structures within grains, which reduced the thermal conductivity by
~50% compared to undoped SrTiO3 samples, due to strong phonon
scattering. A facile method to incorporate metallic inclusions (2.5
wt% Fe/Cu) at grain boundaries in L2 ceramics is demonstrated. The
modified compositions displayed a maximum ZT of ~0.37 at 1000 K for
L2 samples containing metallic inclusions due to increased carrier
concentration (5.5 x 10
21 carriers/cm
3) and carrier mobility (2.4
cm
2/(V.s).The addition of graphene/Graphene Oxide (GO) flakes in
L2 ceramics has been investigated to improve the electrical
conductivity of L2 composites without significantly increasing the
thermal conductivity. Spark plasma sintering (SPS) of the composite
powders at 1473 K and 50 MPa produced dense samples (>95%
relative density) with a homogeneous dispersion of graphene/GO
flakes, for loadings ≤ 1.0 wt%. The effect of interaction and
distribution of graphene/GO flakes within the ceramics on TE
properties is investigated. The composite samples demonstrate
anisotropic ZT values, with 20% improvement in the direction normal
to the orientation of graphene flakes.A novel sintering method has
been proposed which has strong industrial potential. The L2 based
composites were sintered in Air at 1700 K (ramp rate: ±300 K/min),
whilst samples were covered uniformly. Strong reducing conditions
and evolution of secondary phases in the microstructure helped
achieve, the very low electrical resistivity of ~3.0 x 10^(-6)
ohm.m at room temperature. Secondary phases, sub-micron voids in
the grains and A-site vacancies reduced the lattice thermal
conductivity (~2.0 W/m.K), comparable to the lowest lattice thermal
conductivity achievable (~1.5 W/m.K) at 1000 K and obtain a maximum
ZT of 0.4 at 1000 K for L210G-Air/C composites.
Advisors/Committee Members: KINLOCH, IAN IA, Freer, Robert, Kinloch, Ian.
Subjects/Keywords: Thermoelectrics; Bulk Ceramic; Ceramic Graphene composites; SrTiO3; Figure of merit; Solid state sintering; SPS
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Srivastava, D. (2016). Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303607
Chicago Manual of Style (16th Edition):
Srivastava, Deepanshu. “Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303607.
MLA Handbook (7th Edition):
Srivastava, Deepanshu. “Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics.” 2016. Web. 20 Jun 2019.
Vancouver:
Srivastava D. Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303607.
Council of Science Editors:
Srivastava D. Effect of Processing Conditions and Second-Phase
Additives on Thermoelectric Properties of SrTiO3 Based
Ceramics. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303607
University of Manchester
8.
Alharbi, Abdulaziz Nagi D.
Deformation of Hexagonal Boron nitride.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:317073
► Boron nitride (BN) materials have unique properties, which has led to interest in them in the last few years. The deformation of boron nitride materials…
(more)
▼ Boron nitride (BN) materials have unique
properties, which has led to interest in them in the last few
years. The deformation of boron nitride materials including
hexagonal boron nitride, boron nitride nanosheets (BNNSs) and boron
nitride nanotubes have been studied by Raman spectroscopy. Both
mechanical and liquid exfoliations were employed to obtain boron
nitride nanostructures. Boron nitride glass composites were
synthesised and prepared in thin films to be deformed by bending
test in-situ Raman spectroscopy. Hexagonal boron nitride in the
form of an individual flake and as flakes dispersed in glass
matrices has been deformed and Raman measurement shows its response
to strain. The shift rates were, -4.2 cm-1/%, -6.5 cm-1/% for
exfoliated h-BN flake with thick and thin regions and -7.0 cm-1/%,
-2.8 cm-1/% for the h-BN flakes in the h-BN/ glass (I) and glass
(II) composites. Boron nitride nanosheets (BNNSs) shows a G band
Raman peak at 1367.5 cm-1, and the deformation process of BNNSs/
glass composites gives a shift rate of -7.65 cm-1/% for G band.
Boron nitride nanotubes (BNNTs) have a Raman peak with position at
1368 cm-1, and their deformation individually and in composites
gives Raman band shift rates of -25.7 cm-1/% and -23.6 cm-1/%.
Glass matrices shows compressive stresses on boron nitride fillers
and this was found as an upshift in the frequencies of G band peak
of boron nitride materials. Grüneisen parameters of boron nitride
(BN) were used to calculate the residual strains in glass matrices
of BNNSs nanocomposites as well as to estimate the band shift rates
which found to be in agreement with the experimental shift rate of
bulk BN and BNNTs.
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: boron nitride materials; hexagonal boron nitride (h-BN); boron nitride nanosheets (BNNSs); boron nitride nanotubes (BNNTs); nanocomposites; Raman spectroscopy; deformation and glass composites.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alharbi, A. N. D. (2018). Deformation of Hexagonal Boron nitride. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:317073
Chicago Manual of Style (16th Edition):
Alharbi, Abdulaziz Nagi D. “Deformation of Hexagonal Boron nitride.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:317073.
MLA Handbook (7th Edition):
Alharbi, Abdulaziz Nagi D. “Deformation of Hexagonal Boron nitride.” 2018. Web. 20 Jun 2019.
Vancouver:
Alharbi AND. Deformation of Hexagonal Boron nitride. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:317073.
Council of Science Editors:
Alharbi AND. Deformation of Hexagonal Boron nitride. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:317073
University of Manchester
9.
Liu, Yan.
Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301141
► This thesis reports a study of the effects on processing and properties of incorporating nano-scale reinforcements (multiwall carbon nanotubes, MWCNTs) in the matrix of epoxy-…
(more)
▼ This thesis reports a study of the effects on
processing and properties of incorporating nano-scale
reinforcements (multiwall carbon nanotubes, MWCNTs) in the matrix
of epoxy- carbon fibre (CF) laminate composites to produce
multi-scale composites (M-SC). The main aim of this research was to
study the effects of MWCNTs on matrix toughening and the
through-thickness properties of M-SCs based on a commonly used
aerospace grade epoxy resin — triglycidyl-p-aminophenol (TGPAP)
cured with diaminodiphenyl sulphone (DDS). In order to improve
resin processing, diglycidyl ether of bisphenol F (DGEBF) was added
into the TGPAP/DDS system as a reactive diluent. Factorial
experimental design (FED) was used to optimize the composition of
this tri-component system to obtain high 𝑇𝑔 and low resin
viscosity, which gave a TGPAP/DGEBF/DDS system with 30.56 wt.% of
DGEBF and a chemical stoichiometry of 0.5. Three types of MWCNTs
were used; as-received (AR-), base-washed (BW-) and amine
functionalized (NH2-). These were shear-mixed with both the bi- and
tri-component systems using a 3-roll mill to produce nanocomposite
matrices (NCM). The curing behaviour, dispersion state of MWCNTs in
the resin and processability of NCMs were studied to decide upon
the preparation method for the final M-SC. The fracture toughness
(KIC) and the flexural properties of NCM were affected by both
MWCNTs and the matrix type; thus KIC increased by up to 8 % in
TGPAP/DDS NCM but decreased by 23% in TGPAP/DGEBF/DDS NCM with 0.5
wt.% AR-CNTs. The addition of both non-functionalized and
functionalized MWCNTs increased the flexural modulus. The failure
mechanism of NCMs was found to be dominated by the size and
distribution of CNT aggregates and the behaviour of MWCNTs, both
those dispersed in the matrix and in aggregates. The addition of
functionalized MWCNTs increased the interfacial bonding between
MWCNT and epoxy resin and thus improved the mechanical properties.
All the NCM systems were taken forward to manufacture M-SC using a
hybrid resin film infusion (RFI)/hot press process. The fibre
volume fraction and the void content could be controlled at 43 ± 5
% for M-SC with TGPAP/DDS NCM and 60 ± 6 % for M-SC with
TGPAP/DGEBF/DDS NCM. M-SCs were characterised using a range of
tests, including flexural, interlaminar shear strength (ILSS),
mode-II interlaminar fracture toughness (GIIC), low velocity impact
and compression after impact (CAI). The most obvious improvement
occurred for the M-SC with tri-component system with 0.5 wt.% CNTs,
whereILSS increased by 16 % upon adding NH2-CNTs and GIIC increased
significantly on addition of 0.5 wt.% AR-CNTs and NH2-CNTs, by 85%
and 184% respectively. However the effect of MWCNTs on other
properties was at best marginal. For example, for the M-SC with
TGPAP/DDS, the flexural modulus and ILSS only increased by 4.1 %
and 2.3 % with 0.5 wt.% AR-CNT.
N/A
N/A
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
Subjects/Keywords: carbon nanotube; multi-scale composites; carbon fibre; fracture toughness; interlaminar properties; impact; rheology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, Y. (2016). Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301141
Chicago Manual of Style (16th Edition):
Liu, Yan. “Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301141.
MLA Handbook (7th Edition):
Liu, Yan. “Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites.” 2016. Web. 20 Jun 2019.
Vancouver:
Liu Y. Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301141.
Council of Science Editors:
Liu Y. Nano-reinforced Epoxy Resin For Carbon Fibre Fabric
Composites. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301141
University of Manchester
10.
Cui, Zhengxing.
A study of doubly crosslinked microgels and their
composites.
Degree: 2017, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:308151
► This thesis presents a study of pH-responsive doubly crosslinked microgels (DX MGs) and associated investigations to enhance their performance. The potential application of this material…
(more)
▼ This thesis presents a study of pH-responsive
doubly crosslinked microgels (DX MGs) and associated investigations
to enhance their performance. The potential application of this
material is soft tissue engineering, so the research concerns
mechanical properties, other properties like swelling, microporous
and conductivity are also discussed. The MG particles are based on
poly(EA/MAA/x), where EA is the ethyl acrylate, MAA is the
methacrylate acid and x represents the crosslinker. The particles
were subsequently functionalised using glycidyl methacrylate (GMA)
to introduce vinyl groups in the MG particles. The formation of DX
MGs includes a pH triggered swelling of MG particles in the
dispersion to form a physical gel and a heat-triggered free-radical
reaction to form a covalent hydrogel. The starting point of this
study was using graphene oxide (GO) nanosheets to prepare DX MGs
composites with a high modulus. We mixed low concentrations of GO
with MG particles and formed DX MG/GO gels. Both shear and
compressive modulus linearly increased with the concentration of
GO, but the ductility of gels was slightly reduced. The moduli for
the DX MG/GO gels was increased by a factor of 5 - 6 when only 1.0
wt.% of GO was included.The next study used muti-wall carbon
nanotubes (CNTs) which are widely used to prepare electrical
conductive composites. A big challenge for applying CNTs is that
they easily form large aggregates in water, which was solved by the
space-filling and volume excluded properties of MG particles. The
ductility of the composite DX gels increased with CNT
concentration, as did the modulus. The conductivity of gels
significantly increased with the concentration of CNT and they had
a very low percolation threshold. The cytotoxic study for the
composite gels showed that they were not toxic, so they may be
suitable for soft tissue engineering.The effect of crosslinking
monomers in MG preparation was studied in the last part of the
research. Three types of poly(EA/MAA/x) MGs were studied and
compared. The x value was 1 mol. % of divinylbenzene (DVB);
1,4-butanediol diacrylate (BDDA) or a 1:1 mixture of both DVB and
BDDA. The MGs containing DVB demonstrated higher swelling and more
ductile properties and could withstand ~76% of compressive
deformation. Moreover, the effects of intra-MG crosslinking of the
MGs on the swelling behaviour and the mechanical properties were
investigated.
Advisors/Committee Members: KINLOCH, IAN IA, Saunders, Brian, Kinloch, Ian.
Subjects/Keywords: microgels; composites
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cui, Z. (2017). A study of doubly crosslinked microgels and their
composites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:308151
Chicago Manual of Style (16th Edition):
Cui, Zhengxing. “A study of doubly crosslinked microgels and their
composites.” 2017. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:308151.
MLA Handbook (7th Edition):
Cui, Zhengxing. “A study of doubly crosslinked microgels and their
composites.” 2017. Web. 20 Jun 2019.
Vancouver:
Cui Z. A study of doubly crosslinked microgels and their
composites. [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:308151.
Council of Science Editors:
Cui Z. A study of doubly crosslinked microgels and their
composites. [Doctoral Dissertation]. University of Manchester; 2017. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:308151
University of Manchester
11.
Li, Zheling.
Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites.
Degree: 2015, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:267458
► The reinforcement mechanisms in graphene-based nanocomposites have been studied in this project, which primarily consists of three parts: the size and orientation effects of the…
(more)
▼ The reinforcement mechanisms in graphene-based
nanocomposites have been studied in this project, which primarily
consists of three parts: the size and orientation effects of the
graphene-based nano-fillers and their interfacial adhesion with the
matrix. Overall Raman spectroscopy has been demonstrated to be a
powerful technique to study the graphene-based nanocomposites.The
deformation of small size graphene has been followed and a new
model has been established to consider both the non-uniformity of
strain along the graphene and laser intensity within the laser
spot, which interprets the observed unusual Raman band shift well.
Additionally, the deformation of monolayer graphene oxide (GO) has
been followed for the first time. It appears that continuum
mechanics is still valid, and the approximately constant strain
distribution along the GO flake suggests a better stress transfer
efficiency of GO than that of graphene. The spatial orientation of
graphene has been studied based on the Raman scattering obtained
from transverse sections of graphene, where the Raman bands
intensities show a strong polarization dependence. Based on this, a
new model has been established to quantify the spatial orientation
of graphene in terms of an orientation distribution function, and
the spatial orientation of monolayer graphene has been further
confirmed by its surface roughness. This model has been extended to
a variety of graphene-based materials and nanocomposites. It is
also shown how the spatial orientation of graphene-based fillers
affects the mechanical properties of the nanocomposites, through
the first determination of the Krenchel orientation factor for
nanoplatelets.The findings on both the size and orientation effects
have been employed to study the deformation mechanics of bulk GO
reinforced nanocomposite films. It has been demonstrated for the
first time that the effective modulus of GO can be estimated using
the Raman D band shift rate, and this is in agreement with the
value measured using conventional mechanical testing. The effective
modulus of GO is found to be lower than its Young’s modulus,
probably due to the mis-orientation, waviness, wrinkling and
agglomeration of the GO fillers.
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: Graphene; Raman spectroscopy; Nanocomposites; Mechanics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, Z. (2015). Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:267458
Chicago Manual of Style (16th Edition):
Li, Zheling. “Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites.” 2015. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:267458.
MLA Handbook (7th Edition):
Li, Zheling. “Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites.” 2015. Web. 20 Jun 2019.
Vancouver:
Li Z. Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2015. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:267458.
Council of Science Editors:
Li Z. Raman Spectroscopic Studies of the Mechanics of
Graphene-based Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2015. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:267458
University of Manchester
12.
Al-Hilfi, Samir.
CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313458
► Among all the methods of produce graphene, chemical vapour deposition (CVD) is the most promising route, due to the high quality of the graphene film…
(more)
▼ Among all the methods of produce graphene, chemical
vapour deposition (CVD) is the most promising route, due to the
high quality of the graphene film produced and the large
scalability. The mechanism of graphene growth by CVD on a metal
substrate is believed to be controlled by its solubility for carbon
with precipitation dominant at high carbon solubility and surface
diffusion at low solubility. This thesis is exploring the impact of
C solubility in the catalytic substrates, on the CVD growth of
graphene. Cu-Ni alloys show complete solid solubility across their
composition range and can be used to explore the influence of C
solubility on graphene growth. Graphene is grown on Cu-Ni alloys of
composition Cu, Cu70-Ni30, Cu55-Ni45, Cu33-Ni67 and Ni in a
hot-wall CVD reactor. Firstly, the growth was achieved on pure
metals (Cu and Ni) using CH4 as a C source and the produced film
was characterised by Raman spectroscopy and scanning electron
microscopy (SEM). The C profile within the substrate bulk was
measured by glow discharge optical emission stereoscopy (GDOES).
The latter showed the difference in bulk C content between Cu and
Ni, which reflects the influence on the graphitic film on the
surface. The CVD growth of graphene on Cu-Ni alloy showed a
transition from bilayer graphene (BLG) to few layer graphene (FLG)
surface coverage when the Ni content increased, which is
accompanied by an increase in the diffusion of C in the bulk and
incubation time. The cooling rate showed a significant effect on
the graphene surface coverage; however, the influence varied with
Ni content. The fluid flow simulation indicated that the gas
velocity beneath the substrate is very low which results in a lower
mass transfer to the bottom substrate surface. Gas-phase kinetics
simulation reveals the impact of gas residence time on the
concentration of active species; moreover, the concentration
increases down the stream of the flowing gas. Finally, the surface
reactions of the CH4/H2 mixture model showed a good agreement with
the experimental observations under low growth pressure; however,
it failed at high growth pressure.
Advisors/Committee Members: KINLOCH, IAN IA, Derby, Brian, Kinloch, Ian.
Subjects/Keywords: CVD; Cu-Ni alloy; Carbon solubility
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Al-Hilfi, S. (2018). CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313458
Chicago Manual of Style (16th Edition):
Al-Hilfi, Samir. “CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313458.
MLA Handbook (7th Edition):
Al-Hilfi, Samir. “CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY.” 2018. Web. 20 Jun 2019.
Vancouver:
Al-Hilfi S. CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313458.
Council of Science Editors:
Al-Hilfi S. CHEMICAL VAPOUR DEPOSITION OF GRAPHENE ON COPPER-NICKEL
ALLOY. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313458
University of Manchester
13.
Zhao, Xin.
Mechanical Properties of Graphene and Graphene-based
Nanocomposites.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313601
► A detailed review has been undertaken upon graphene and graphene reinforced epoxy nanocomposites. In addition, the literature on Raman spectroscopy and its application in graphene…
(more)
▼ A detailed review has been undertaken upon graphene
and graphene reinforced epoxy nanocomposites. In addition, the
literature on Raman spectroscopy and its application in graphene
and graphene nanocomposites has also been reviewed. The deformation
and fracture behaviour of one-atom-thick monolayer graphene has
been studied in detail. Monolayer graphene flakes with different
widths and shapes were successfully prepared by mechanical
exfoliation and pressed onto PMMA beams. It has been possible to
follow the fracture behaviour of one-atom-thick monolayer graphene
by deforming the PMMA beams. Through in-situ Raman mapping at
different strain levels, the strains over the whole flake were
determined from the shift of the graphene Raman 2D band. The
fracture of the flakes was observed from the development of zero
strain lines that prefer to form in a direction perpendicular to
the strain axis but it still tends to follow the zig-zag or
armchair crystallographic direction in graphene single crystal if
the angle is close. It was found that the strength of the monolayer
graphene flakes with no clear edge defects decreases with an
increase in the flake width. The strength dropped to only 5 GPa for
some large flakes, much less than the reported 130 GPa. This was
thought to be due to the presence of topological defects that may
form pseudo cracks. It was also found that the strength for small
monolayer graphene flakes with pre-existing cracks and notched
edges is only about 4 to 5 GPa. Seven different kinds of graphene
materials with different microstructural parameters including flake
width, thickness, defect concentration and chemical
functionalization have been studied and used to fabricate the
nanocomposites with an epoxy matrix. Graphene materials with higher
aspect ratios have been found to give better reinforcement than
those with lower aspect ratios. Oxidative functional groups on
graphene flakes can help achieve a better dispersion but they also
can compromise the mechanical properties of the graphene materials.
The strength of pristine graphene reinforced epoxy nanocomposites
is dominated by the width of the graphene flakes and the dispersion
quality of graphene materials within epoxy matrix. The narrower the
graphene flakes or the better the dispersion, the higher the
strength. Defects in the functionalised graphene flakes have
potential to nucleate cracks within the nanocomposites and cause
premature fracture that reduces the strength.
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: Raman; Graphene; Strength; Toughness; Reinforcement Effect
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhao, X. (2018). Mechanical Properties of Graphene and Graphene-based
Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313601
Chicago Manual of Style (16th Edition):
Zhao, Xin. “Mechanical Properties of Graphene and Graphene-based
Nanocomposites.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313601.
MLA Handbook (7th Edition):
Zhao, Xin. “Mechanical Properties of Graphene and Graphene-based
Nanocomposites.” 2018. Web. 20 Jun 2019.
Vancouver:
Zhao X. Mechanical Properties of Graphene and Graphene-based
Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313601.
Council of Science Editors:
Zhao X. Mechanical Properties of Graphene and Graphene-based
Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313601
University of Manchester
14.
Li, Suhao.
Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313086
► The microstructure and properties have been investigated in nanocomposites consisting of graphite nanoplatelets (GNPs) in natural rubber (NR) and nitrile butadiene rubber (NBR). Nanocomposites with…
(more)
▼ The microstructure and properties have been
investigated in nanocomposites consisting of graphite nanoplatelets
(GNPs) in natural rubber (NR) and nitrile butadiene rubber (NBR).
Nanocomposites with four different loadings of three different
sized GNPs (nominal lateral dimension of 5, 15 and 25 microns) were
prepared that were bench-marked against nanocomposites loaded with
N330 carbon black. The materials were processed using conventional
melt-processing methods in a two-roll mill and the composition of
the nanocomposites was confirmed by thermogravimetric analysis. The
microstructure of the nanocomposites was characterised though a
combination of scanning electron microscopy, polarised Raman
spectroscopy and X-ray computer tomography (CT) scanning, where it
was shown that the GNPs were well dispersed with a preferred
orientation parallel to the surface of the nanocomposite sheets.
The mechanical properties of the nanocomposites were evaluated
through tensile testing, Shore A hardness testing and tear testing.
It was shown that, for a given loading, there was a three times
greater increase in stiffness for the GNPs than for the carbon
black. The size effect of the particles is significant in the
mechanical properties. Stress transfer from the NR and the NBR to
the GNPs was evaluated from stress-induced Raman bands shifts
indicating that the effective Young’s modulus of the GNPs in the
NR was only of the order of 100 MPa, similar to the value evaluated
using the rule of mixtures from the stress-strain data. A
comprehensive theory was developed to explain the deficiency of the
stress transfer in soft matrix systems. Transport properties
including solvent diffusion and thermal conductivity were
investigated. Anisotropic swelling was observed for all the GNPs
composites due to the orientation of the GNP flakes. The diffusion
coefficient decreases with the increasing loading of the fillers
and the increasing particle size. Thermal conductivity was enhanced
with the addition of the fillers and the largest particle gives
rise to the highest enhancement.
For the CT scanning videos of GNP/NR
nanocomposites, please see the following link
https://link.springer.com/article/10.1007/s10853-017-1144-0.
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: GNP; Elastomer; Structure; Mechanical properties; Swelling behaviour; Thermal conductivity; Stress transfer; Shear-lag theory; Raman band shift
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, S. (2018). Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313086
Chicago Manual of Style (16th Edition):
Li, Suhao. “Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313086.
MLA Handbook (7th Edition):
Li, Suhao. “Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets.” 2018. Web. 20 Jun 2019.
Vancouver:
Li S. Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313086.
Council of Science Editors:
Li S. Structure/Property Relationships in Elastomers Filled
with Graphite Nanoplatelets. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313086
15.
Li, Zhe.
Routes towards Manufacturing Janus Carbon
Nanotubes.
Degree: 2013, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:215976
► This project aimed to produce Janus carbon nanotubes (CNTs) that have onehydrophobic and one hydrophilic end. These particles could then be manipulated intwo-phase polymer systems…
(more)
▼ This project aimed to produce Janus carbon
nanotubes (CNTs) that have onehydrophobic and one hydrophilic end.
These particles could then be manipulated intwo-phase polymer
systems or at liquid-liquid interfaces enabling new routes to
novelnanotube architectures.Vertically aligned arrays of MWNTs were
grown on silicon wafers by an injectionCVD method using toluene as
carbon source and ferrocene as catalyst. The lengths ofCNTs were
found to be affected by the reaction time and the flowrate of
carrier gas.The optimum growth conditions for aligned CNT arrays
which could be masked were100 ml/min argon as carrier gas and a
reaction time of 1 h.Partial masking which protected half the
length of the CNT arrays has been used inorder to subsequently
realise asymmetric functionalisation. It was not found possibleto
partially mask the CNT arrays using polystyrene by various
approaches. Howeverpartial masking was achieved by the
thermal-impregnation of paraffin wax. It wasfound that impregnating
at 90 ºC for 3 min led to wax masking the top half of thealigned
CNTs, which was suitable for further modification. Theoretical
models werealso considered to interpret the thermal-impregnation
process of paraffin wax into theCNTs array.Two routes were proposed
to selectively functionalise the masked nanotubes, namelyplasma
treatment, and electrochemical oxidation. Decline of water contact
angles andincrease of ID/IG ratio proved plasma treatment to be
effective to functionalise alignedCNTs array. The paraffin wax on
partially masked array was sacrificially etched byplasma and
prevented CNT functionalisation. As a consequence, the wax-masked
endof nanotubes remained hydrophobic, while the unmasked end became
nearlyhydrophilic.Electrodes were prepared from the aligned CNT
arrays for the electrochemicaloxidation. CV and Raman spectra
indicated the formation of oxygen-containingfunctional groups on
the CNTs. A constant potential of 1.4 V for 30 s was found to
beefficient to electrochemically oxidise the CNTs. According to the
contact anglemeasurements, the electrochemically oxidised sample
could be considered as Januscarbon nanotubes, which are hydrophilic
on one side and hydrophobic on the other.
Advisors/Committee Members: Kinloch, Ian.
Subjects/Keywords: Carbon nanotubes; Janus particles
…MPhil
The University of Manchester
September 2013
This project aimed to produce Janus carbon… …x29; and s/he has given The
University of Manchester certain rights to use such Copyright…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, Z. (2013). Routes towards Manufacturing Janus Carbon
Nanotubes. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:215976
Chicago Manual of Style (16th Edition):
Li, Zhe. “Routes towards Manufacturing Janus Carbon
Nanotubes.” 2013. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:215976.
MLA Handbook (7th Edition):
Li, Zhe. “Routes towards Manufacturing Janus Carbon
Nanotubes.” 2013. Web. 20 Jun 2019.
Vancouver:
Li Z. Routes towards Manufacturing Janus Carbon
Nanotubes. [Internet] [Doctoral dissertation]. University of Manchester; 2013. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:215976.
Council of Science Editors:
Li Z. Routes towards Manufacturing Janus Carbon
Nanotubes. [Doctoral Dissertation]. University of Manchester; 2013. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:215976
16.
Li, Yanning.
Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures.
Degree: 2014, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217714
► Silica and titania nanoparticles have been produced by using carbon nanotubes (CNTs) and graphene as templates in a sol-gel reaction. A range of Fmoc terminated…
(more)
▼ Silica and titania nanoparticles have been produced
by using carbon nanotubes (CNTs) and graphene as templates in a
sol-gel reaction. A range of Fmoc terminated amino-acids (Fmoc-AAs)
were studied as surface modifiers to encourage the templating on
the nanocarbons. After annealing the deposited structures, the
carbon templates were either left in place to give hybrid
structures or oxidized to leave pure inorganic
nanoparticles.Absorption studies were initially conducted to
identify Fmoc-AAs that would bind well to the CNTs. Fmoc-Trp had
the best affinity for CNTs out of the amino acids studied. The
fully reversible nature of the binding process was demonstrated via
the desorption of Fmoc-AAs from CNTs in water. The equilibrium data
were found to be well described by the Freundlich isotherm model.
The competitive binding from a library of Fmoc-AAs on graphite was
developed to efficiently identify the strongest binding
candidate.The synthesis of CNT-SiO2 and CNT-TiO2 nanohybrids were
successfully demonstrated. The morphology of the hybrids was found
to be dependent on the CNT:precursor and Fmoc-AA:CNT ratios.
Fmoc-AAs were believed to play a dual role: (1) electrostatically
stabilizing the NT dispersion and (2) the functionalities from the
side chains of the amino acids providing binding sites for SiO2 and
TiO2 deposition. Uniform anatase nanotubes (NTs) were synthesized
after calcination of the CNT-TiO2 nanohybrids. Both the inner
diameter and wall thickness of the synthesized TiO2 NTs were
controlled by the dimension of CNT templates and the ratio of
CNT:precursor. The transition from anatase to rutile phase was
found to be affected by heating temperature, pre-treatment and ramp
rate. A simple route towards the production of TiO2 NT arrays was
also demonstrated by using aligned CNT arrays as templates in the
presence of the Fmoc-AAs.Graphene based nanohybrids were
synthesized in the presence of graphene oxide (GO), Fmoc-Trp
stabilized base-washed graphene oxide (bwGO) and exfoliated
graphene via the sol-gel process. It was found that the morphology
of the products was highly dependent on the reaction media.
Graphene dispersions were prepared by direct exfoliation of
graphite in Fmoc-Trp solution. Raman, TEM and AFM analyses
suggested the dispersion comprised of mainly few layer graphene
(<5 layers) with a broad size distribution and that the defects
introduced during sonication were predominately associated with the
formation of new flake edges due to sonication-induced cutting.A
preliminary study was conducted on the silicification of Fmoc-Y and
Fmoc-FY self-assembled hydrogels. The presence of a high density of
–OH group on the nanofibers’ surface was found to promote silica
deposition.
Advisors/Committee Members: Kinloch, Ian.
…rights in it (the “Copyright”) and s/he
has given The University of Manchester…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, Y. (2014). Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217714
Chicago Manual of Style (16th Edition):
Li, Yanning. “Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures.” 2014. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217714.
MLA Handbook (7th Edition):
Li, Yanning. “Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures.” 2014. Web. 20 Jun 2019.
Vancouver:
Li Y. Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217714.
Council of Science Editors:
Li Y. Production of inorganic nanohybrids by the templating of
carbon and peptide nanostructures. [Doctoral Dissertation]. University of Manchester; 2014. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217714
17.
Aranga Raju, Arun Prakash.
Graphene Functional Composites.
Degree: 2012, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:159422
► Raman spectroscopy is a powerful technique for characterizing carbon materials and their derivatives. In this project, Raman spectroscopy was used to characterize graphene and its…
(more)
▼ Raman spectroscopy is a powerful technique for
characterizing carbon materials and their derivatives. In this
project, Raman spectroscopy was used to characterize graphene and
its composites with the ultimate aim of developing graphene
composites for use as wide area strain sensors in structural
engineering applications. Model coating systems were made by
depositing micromechanically-cleaved graphene onto PMMA substrates.
These sensors could sense uniaxial strain to an accuracy of ± 720
microstrain over repeated cyclic deformation. This relatively low
accuracy was due to both the strain hardening behaviour of graphene
and the interfacial damage that occurred between the graphene and
the matrix during the deformation. The interfacial damage led to
increasing energy dissipation during each cycle and a build-up of
residual stress. The strain sensitivity of micromechanically
cleaved graphene deposited on engineering materials like spring
steel was also demonstrated. Finally, in order to assess the
scale-up potential of the graphene coatings, composites were
prepared from solvent- phase exfoliated graphene and commercial
graphene nanoplatelets, using either casting or compound mixing
methods. In order to achieve large flakes for maximum stress
transfer, the solvent phase exfoliation of graphene as a function
of sonication time was investigated. The higher the sonication
time, the higher concentration of graphene achieved. But presence
of large graphite like flakes were evident from the Raman
spectroscopy and SEM results, suggesting that low rotation speeds
of 500 rpm in NMP was not sufficed enough to remove larger/thicker
flakes.
Advisors/Committee Members: Kinloch, Ian.
Subjects/Keywords: graphene composite; strain sensor; Raman spectroscopy; accuracy
…University of Manchester certain rights to use such Copyright, including for administrative… …when Geim and his co-workers at The University of Manchester produced graphitic
sheets with… …coatings were evaluated as strain sensors as
part of a University of Manchester Intellectual… …layer graphene on SiO2/Si substrate observed by Geim and his co-workers
at University of… …x5D; In particular, Geim and
his co-workers isolated graphene at The University of…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Aranga Raju, A. P. (2012). Graphene Functional Composites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:159422
Chicago Manual of Style (16th Edition):
Aranga Raju, Arun Prakash. “Graphene Functional Composites.” 2012. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:159422.
MLA Handbook (7th Edition):
Aranga Raju, Arun Prakash. “Graphene Functional Composites.” 2012. Web. 20 Jun 2019.
Vancouver:
Aranga Raju AP. Graphene Functional Composites. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:159422.
Council of Science Editors:
Aranga Raju AP. Graphene Functional Composites. [Doctoral Dissertation]. University of Manchester; 2012. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:159422
18.
Xu, Haixia.
AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY.
Degree: 2011, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128758
► Nanoscale, conductive wires fabricated from organic molecules have attracted considerable attention in recent years due to their anticipated applications in the next generation of optical…
(more)
▼ Nanoscale, conductive wires fabricated from organic
molecules have attracted considerable attention in recent years due
to their anticipated applications in the next generation of optical
and electronic devices. Such highly ordered 1D nanostructures could
be made from a number of routes. One route of particular interest
is to self-assemble the wires from biomolecules due to the wide
range of assembly methods that can be adapted from nature. For
example, biomolecules with aromatic motifs can be self-assembled so
that good stacking is achieved in the resultant nanostructure.
An additional advantage of using biomolecules is that it enables
the interface of the electronic materials with biological systems,
which is important for many applications, including nerve cell
communication and artificial photosynthesis. In this study,
nanowires were prepared by the molecular self-assembly of
oligopeptides that were coupled to aromatic components. In order to
achieve charge transport though the nanowires, it was imperative
that the aromatic components were arranged so that there was
stacking with very few structural defects. Therefore, enzymes
were used to control the formation of the hydogelators which
subsequently self-assembled to produce nanowire networks. Two main
systems were studied in this thesis.In the first system,
hydrogelators were produced from aromatic peptide amphiphiles via
the enzymatic hydrolysis of the methyl ester of
fluorenylmethoxycarbonyl (Fmoc)-di/tripeptides. These hydrogelators
formed nanostructures due to -stacking between the Fmoc groups
and H-bonding between the peptides. The nanostructures in turn
produced macroscale gel networks. The nanostructures were analyzed
by wide angle X-ray diffraction and fluorescence spectroscopy. A
combination of Fourier transform infra-red (FTIR), Transmission
Electron Microscopy (TEM), Cryo-TEM, and Atomic Force Microscopy
(AFM) was used to characterize the networks. The charge transport
properties of the dried networks were studied using impedance
spectroscopy. Fmoc-L3 was found to assemble into nanotubes whose
walls consisted of 3 self-assembled layers and possessed inner and
outer diameters of ~ 9 nm and ~ 18 nm, respectively. The Fmoc-L3
networks were structurally stabile and were electronically
conductive under a vacuum. The sheet resistance of the peptide
networks increased with relative humidity due to the increasing
ionic conductivity. The resistance of the networks was 0.1 MΩ/sq in
air and 500 MΩ/sq in vacuum (pressure: 1.03 mbar) at room
temperature. The networks had a band gap of between 1 to 4 eV as
measured by UV-Vis spectroscopy and the temperature-impedance
studies. Possible routes for aligning the Fmoc-L3 networks were
studied in an attempt to improve their conductivity in one
direction. In particular, the peptides were assembled under an
electric field (0 to 3.75 kV/cm). Random networks were produced at
low field strengths, whereas a degree of alignment was obtained at
a field strength of 3.75 kV/cm. The conductivity of the aligned
networks…
Advisors/Committee Members: Kinloch, Ian.
Subjects/Keywords: self-assembly; peptide nanotubes; hydrogel;
nanostructures; conductivity; alignment
…x28;the “Copyright”) and she has given The University of Manchester
certain rights to… …Masaki from the University of Manchester
Chemistry Department, for his generous help with… …from Materials Science in the
University of Manchester for revolutionizing my understanding…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Xu, H. (2011). AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128758
Chicago Manual of Style (16th Edition):
Xu, Haixia. “AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY.” 2011. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128758.
MLA Handbook (7th Edition):
Xu, Haixia. “AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY.” 2011. Web. 20 Jun 2019.
Vancouver:
Xu H. AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY. [Internet] [Doctoral dissertation]. University of Manchester; 2011. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128758.
Council of Science Editors:
Xu H. AN INVESTIGATION OF THE CONDUCTIVITY OF PEPTIDE
NANOSTRUCTURED HYDROGELS VIA MOLECULAR SELF-ASSEMBLY. [Doctoral Dissertation]. University of Manchester; 2011. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:128758
University of Manchester
19.
Mcardle, Trevor.
Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis.
Degree: 2015, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:272220
► This thesis investigates the adsorption mechanisms and changes in activity of bilirubin oxidase from Myrothecium verrucaria immobilised to gold- and silica-modified surfaces. This enzyme is…
(more)
▼ This thesis investigates the adsorption mechanisms
and changes in activity of bilirubin oxidase from Myrothecium
verrucaria immobilised to gold- and silica-modified surfaces. This
enzyme is used as an efficient bioelectrocatalyst for the
four-electron oxygen reduction in fuel cells. An electrochemical
quartz crystal microbalance with dissipation monitoring (E–QCM–D)
was used to show how applying a constant potential to bilirubin
oxidase adsorbed to a carboxylate-terminated gold electrode
resulted in activity loss attributed to structural rearrangement of
the adsorbed enzyme layer. When a varying potential was applied,
rapid enzyme deactivation occurred, with no mitigation of activity
loss through covalent attachment to the electrode.The E-QCM-D was
further used to observe how changing enzyme concentration affects
the adsorption mechanics and catalytic activity of the adsorbed
layer. An optimum concentration produced greatest activity and
stability, with lower concentrations denaturing more readily, and
higher concentrations adopting an unfavourable geometry for
electron transfer. Surface functionality showed adsorption to
hydrophobic methyl- terminated electrodes revealed a rigid layer
with reduced catalytic activity. Ammonium terminated surfaces
resisted denaturation, but misorientated the enzyme for efficient
electrocatalysis. Increasing the chain length of the surface
modifiers increased the enzyme–electrode distance; this decreased
activity for the carboxylate surface and removed the activity for
methyl- or ammonium-terminated surfaces. Dual polarisation
interferometry further showed no enzyme denaturation when it was
adsorbed to amine and sulfonic acid surfaces.Enzyme adsorption
under an applied constant potential caused a decrease in both mass
loading and activity when compared to open circuit potential
adsorption. The presence of an applied potential did not cause
increased layer denaturation, but changed the orientation of the
enzyme in a position unfavourable for electron transfer. Lower
applied potential give lower mass loadings, yet similar surface
mechanics and activity per adsorbed enzyme.Chemical modification to
pristine graphene showed targeted interactions with biomolecules
such as proteins and fluorophores. This surface modification has
the potential to be adapted towards adsorption of bilirubin oxidase
for fuel cell catalysis and other electrochemical sensing
applications.The observations in this thesis show how the E–QCM–D
and DPI can provide a more expansive picture of the applicability
of redox enzymes in fuel cell systems. Preventative steps need to
be taken in order to maintain an enzyme’s structural integrity and
in turn its catalytic competency. Without such provisions the
observations above suggest that redox enzymes have a finite
lifetime when under conditions approximating fuel cell
systems.
Advisors/Committee Members: DRYFE, ROBERT RAW, KINLOCH, IAN IA, Dryfe, Robert, Kinloch, Ian, Blanford, Christopher.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mcardle, T. (2015). Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:272220
Chicago Manual of Style (16th Edition):
Mcardle, Trevor. “Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis.” 2015. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:272220.
MLA Handbook (7th Edition):
Mcardle, Trevor. “Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis.” 2015. Web. 20 Jun 2019.
Vancouver:
Mcardle T. Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis. [Internet] [Doctoral dissertation]. University of Manchester; 2015. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:272220.
Council of Science Editors:
Mcardle T. Optimising the adsorption of bilirubin oxidase using dual
polarisation interferometry and an electrochemical quartz crystal
microbalance with dissipation analysis. [Doctoral Dissertation]. University of Manchester; 2015. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:272220
University of Manchester
20.
Lewis, Amanda.
Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper.
Degree: 2014, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:216370
► The chemical vapour deposition (CVD) of graphene is the most promising route for production of large-area graphene films. However there are still major challenges faced…
(more)
▼ The chemical vapour deposition (CVD) of graphene is
the most promising route for production of large-area graphene
films. However there are still major challenges faced by the field,
including control of the graphene coverage, quality, and the number
of layers. These challenges can be overcome by developing a
fundamental understanding of the graphene growth process. This
thesis contributes to the growing body of work on graphene CVD by
uniquely exploring the gas phase chemistry and fluid flow in the
hot-wall graphene CVD reactor.Firstly the reported parameter space
for the hot-wall CVD of graphene on copper was mapped, informing
the subsequent work and providing a resource for the wider
community. A CVD reactor was constructed to extend this parameter
space to lower pressures using methane as a carbon source, and the
films were categorised using scanning electron microscopy, Raman
spectroscopy and optical dark field microscopy.The latter showed
particular promise as a rapid and non-destructive characterization
technique for identifying graphene films on the deposition
substrate. The gas phase equilibrium compositions were calculated
across the parameter space, and correlations between the
stabilities of various chemical species and the types of deposition
were drawn. This laid a foundation for the remainder of the
experimental work, which explored the effect of diluent gases and
different feedstocks on the growth to understand the importance of
the identified correlations.Diluent gases (argon and nitrogen) were
added to the experimental conditions and the thermodynamic model,
and were found to reduce the degree of coverage of the graphene
films. This result shows that the CVD of graphene is sensitive to
factors other than the thermodynamic state parameters, such as the
fluid flow profile in the reactor and inelastic collisions between
the higher mass diluent gases and the methane/hydrogen/copper
system. Using a nitrogen diluent raises the equilibrium carbon
vapour pressure and seems to allow larger graphene grains to form.
This suggests that thermodynamic factors can contribute to the
nucleation of graphene films. Varying the hydrocarbon feedstock and
the process conditions indicated that the structure of the
deposited carbon is closely related to the nucleation kinetics.
Three nucleation regimes are associated with different types of
deposition: homogeneous nucleation with amorphous carbon or soot;
uncatalysed nucleation with multilayer deposition; and nucleation
processes controlled by the copper substrate withpredominantly
monolayer deposition. Changing the feedstock from methane to
acetylene resulted in poorer graphene coverage, showing that
thermodynamic control does not apply in the portion of the
parameter space at the high temperatures and lowpressures most
successfully used for the deposition of continuous graphene
monolayers.
Under certain conditions, heating copper in the
presence of hydrogen and hydrocarbons allows a monolayer of carbon
atoms, a graphene coating, to form on the metal surface.…
Advisors/Committee Members: DERBY, BRIAN B, Derby, Brian, Kinloch, Ian.
Subjects/Keywords: Graphene; CVD; copper; thermodynamics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lewis, A. (2014). Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:216370
Chicago Manual of Style (16th Edition):
Lewis, Amanda. “Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper.” 2014. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:216370.
MLA Handbook (7th Edition):
Lewis, Amanda. “Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper.” 2014. Web. 20 Jun 2019.
Vancouver:
Lewis A. Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:216370.
Council of Science Editors:
Lewis A. Fundamental Studies of the Chemical Vapour Deposition of
Graphene on Copper. [Doctoral Dissertation]. University of Manchester; 2014. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:216370
University of Manchester
21.
Viita, David.
Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour.
Degree: 2014, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217580
► This thesis, by David Viita, submitted for the degree of Doctor of Philosophy to the University of Manchester in September 2013, entitled “Static and Dynamic…
(more)
▼ This thesis, by David Viita, submitted for the
degree of Doctor of Philosophy to the
University of
Manchester in
September 2013, entitled “Static and Dynamic Raman Spectroscopic
Studies of Woven Body Armour”, studies the behaviour under strain
of the high strength para-aramid polymer fibre, Twaron® and fabrics
woven from it using Raman spectroscopy. These fabrics are widely
used in armour and the project aimed to understand how strain
developed in them during penetration. Three key conclusions were
reached. Firstly, as well as shifting near-linearly with strain,
the 1610 cm-1 spectral peak of Twaron broadens reversibly with
strain. The broadening follows an exponential curve. Others have
attributed this broadening to either molecular-level shear lag or
misorientation of the pleated crystallites causing unequal loading.
However, analysis of the data herein contradicts both
hypotheses.Secondly, in order to understand the shear lag that
occurs as fibres are strained over metal surfaces, Twaron yarns and
filaments were stretched over metal rods to replicate and extend
previous work by Kuo. Reasonable agreement with Kuo was found.
Fabric were then strained step-wise by indenting the fabric with a
bullet-shaped head. The strain in these fabrics was mapped from
yarn and sub-yarn (microscale) levels through Raman spectroscopy,
using the dependencies measured earlier in the thesis. The strain
along yarns was found to decay with distance from the bullet, due
to friction with transverse yarns. This data was initially fitted
with 2D Gaussian and Voigt curves. A theoretical underpinning was
then developed presenting a similar, yet distinct, behaviour to an
exponential decay. Typically, the strain decayed to 36% of its peak
value by 15 yarns distance (1.8 cm) from the bullet apex. The
strain was also mapped in two-layer fabrics which had a
misorientation between the layers. These two-layer fabrics had a
more “circular” strain profile than single-layer fabrics.Finally,
the measurement of strain in real time through Raman spectroscopy
was considered (“dynamic strain” tests). A spectrum simulator was
built in Excel® to predict how Raman spectra would appear when
taken from samples which changed strain state during the
measurement. This simulation produced realistic-looking spectra and
were analysed in the same manner as real data. The main difference
between spectra taken at a single strain and those taken with
changing strain was an increase in the apparent width of the peaks
due to their shifting during the measurement. Noise was added to
the simulated spectra through analysis of experimental data taken
at different exposure times.The simulation was then used to predict
the minimum change in strain that could be measured given the
signal noise. This is essential groundwork to interpreting spectra
taken during a shooting test on a fabric panel. It was predicted
that static curves could be distinguished from dynamic ones (0% to
3.4% strain) in spectra taken in 50 ms or less. Longer exposure
times enabled slower strain-changes to be…
Advisors/Committee Members: YOUNG, ROBERT RJ, Young, Robert, Kinloch, Ian.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Viita, D. (2014). Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217580
Chicago Manual of Style (16th Edition):
Viita, David. “Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour.” 2014. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217580.
MLA Handbook (7th Edition):
Viita, David. “Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour.” 2014. Web. 20 Jun 2019.
Vancouver:
Viita D. Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217580.
Council of Science Editors:
Viita D. Static and Dynamic Raman Spectroscopic Studies of Woven
Body Armour. [Doctoral Dissertation]. University of Manchester; 2014. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:217580
University of Manchester
22.
Cao, Gaoxiang.
Multi-functional epoxy/graphene nanoplatelet
composites.
Degree: 2016, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301217
► Graphene nanoplatelets (GNP) with thickness of 6 ~ 8 nm and lateral dimension of 5 μm (M5) and 25 μm (M25) have been used to…
(more)
▼ Graphene nanoplatelets (GNP) with thickness of 6 ~
8 nm and lateral dimension of 5 μm (M5) and 25 μm (M25) have been
used to prepare epoxy composites. Epoxy composites were fabricated
initially by shear mixing to investigate the effects of filler type
on the structure and properties of composites. The complex
viscosity of GNP-epoxy mixture was found to increase by almost
three orders of magnitude going from the neat epoxy to the 8 wt.%
loading, leading to difficulties in their processing. Scanning
electron microscopy of the composites showed that both fillers
aggregated at high loadings with the M25 buckling more easily due
to its larger diameter, which compromises its aspect ratio
advantage over M5, resulting in only slightly better mechanical
performance. Polarized Raman spectroscopy revealed that both M5 and
M25 were randomly distributed in the epoxy matrix, After adding M5
and M25 fillers, the storage modulus increase with the filler
loadings, however, the glass transition temperature (Tg) drops
slightly after initial incorporation, then rises with further
filler addition attributed to the pin effects of filler
aggregations. In terms of electrical property, M25 has lower
percolation (1 wt.%) than M5 composites due to its bigger aspect
ratio, which enable M25 to form a conductive network more
efficiently. Furthermore, M25 composites also have slightly better
thermal and mechanical properties over that of M5 composites.
However, the difference is not significant considering the aspect
ratio of M25 is five times of that of M5. The reason is that the
aggregation and buckling of M25 compromise its advantage over M5.
Due to the better performance of M25 as filler, M25/epoxy
composites were prepared by shear mixing, solvent compounding and
three-roll mill. Samples made by solvent compounding display the
lowest percolation threshold (0.5 wt.%), related to its relatively
uniform dispersion of M25 in matrix, resulting in higher thermal
conductivity and better mechanical properties. Water uptake in a
water bath at 50 °C took 75 days to be saturated. Higher loaded
samples have lower diffusion coefficient because of the barrier
effects of GNP fillers, but have higher maximum water absorbed,
which is owing to filler aggregation. Properties test of aged and
unaged specimens show thermal conductivity of the aged was enhanced
due to water’s higher thermal conductivity than epoxy resin matrix,
while electrical performance was compromised due to the swelling
effects caused by absorbed water. The mechanical properties of aged
samples also dropped slightly due to plasticization
effects.
Advisors/Committee Members: YOUNG, ROBERT RJ, Young, Robert, Kinloch, Ian.
Subjects/Keywords: Eopxy; Graphene nanoplatelet; composites; Impedance
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cao, G. (2016). Multi-functional epoxy/graphene nanoplatelet
composites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301217
Chicago Manual of Style (16th Edition):
Cao, Gaoxiang. “Multi-functional epoxy/graphene nanoplatelet
composites.” 2016. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301217.
MLA Handbook (7th Edition):
Cao, Gaoxiang. “Multi-functional epoxy/graphene nanoplatelet
composites.” 2016. Web. 20 Jun 2019.
Vancouver:
Cao G. Multi-functional epoxy/graphene nanoplatelet
composites. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301217.
Council of Science Editors:
Cao G. Multi-functional epoxy/graphene nanoplatelet
composites. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:301217
University of Manchester
23.
Saeed, Maryam.
CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS).
Degree: 2017, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:312095
► Graphene, a two-dimensional sheet of sp2 carbon, has been the focus of research communities across the globe due to its remarkable combination of properties. Chemical…
(more)
▼ Graphene, a two-dimensional sheet of sp2 carbon,
has been the focus of research communities across the globe due to
its remarkable combination of properties. Chemical vapour
deposition (CVD) has the potential to produce graphene films on a
large-scale, enabling its use in many applications. Typically,
graphene is grown on a solid substrate, with the structure of the
substrate influencing the resulting graphene. Thus, there has been
a move towards using liquid metal substrates in recent years.
However, whilst there are many studies reporting on the effect of
growth parameters of CVD graphene over solid copper (Cu) and nickel
(Ni) substrates, there is little on liquid substrates. This
challenge is addressed in this thesis, with a consideration of the
material properties of liquid substrates (e.g. carbon solubility)
on CVD graphene nucleation and growth. In particular, low melting
point substrates were studied with the aim of transferring the
graphene directly from the liquid metal without any need to
solidify it. Firstly, the graphene films were grown by atmospheric
pressure CVD (APCVD) on liquid Cu substrates, which were found to
show characteristic hexagonal defects when the Cu was held in a
molybdenum (Mo) crucible not present when using a tungsten (W)
crucible. These defects were identified as thin precipitates of
Mo2C, highlighting the effect of the support substrate on the
quality of the grown graphene film. Thermodynamic calculations
indicated that under typical CVD conditions, using a CH4/H2 process
gas, Mo2C is stable in the presence of C whereas WC is not. A
mechanism driven by the vapour phase transport of the volatile MoO3
phase from the metal boat surface was subsequently proposed. Low
melting point metal, tin (Sn) and indium (In) were then studied as
growth substrates. The effect of hydrogen, hydrocarbon feedstock,
growth temperature, reactants' residence time and growth time were
also explored. The relationship between the partial pressure of the
reactive gases and the resultant graphene was found to differ
across the two metals. That is, high quality graphene on liquid Sn
was obtained at high partial pressure of the hydrocarbon and long
residence time. Conversely, in the case of high quality graphene on
liquid In, the opposite was found to occur. The excellent catalytic
nature of Cu in graphene growth is well-known. Thus, after
optimising the growth conditions for high quality graphene on
liquid Sn and In, this study aimed to explore the effect of adding
different doses of Cu to form Cu-Sn and Cu-In alloys. Different
compositions of low melting alloys, Sn-In have also been explored.
It was found that the optimal growth conditions for the alloys
matched those of the dominant metals, with sub- optimal growth
occurring for the alloys with relatively even concentrations of
metals. Finally, this study attempted to find direct transfer
routes of graphene from liquid growth substrates, with the aim of
avoiding the strain and damage induced in traditional transfer
approaches. Various transfer substrates with…
Advisors/Committee Members: DERBY, BRIAN B, Kinloch, Ian, Derby, Brian.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Saeed, M. (2017). CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS). (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:312095
Chicago Manual of Style (16th Edition):
Saeed, Maryam. “CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS).” 2017. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:312095.
MLA Handbook (7th Edition):
Saeed, Maryam. “CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS).” 2017. Web. 20 Jun 2019.
Vancouver:
Saeed M. CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS). [Internet] [Doctoral dissertation]. University of Manchester; 2017. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:312095.
Council of Science Editors:
Saeed M. CVD GRAPHENE ON LIQUID SUBSTRATES (REPLACEMENTS FOR ITO
IN SOLAR AND DISPLAY APPLICATONS). [Doctoral Dissertation]. University of Manchester; 2017. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:312095
University of Manchester
24.
Wang, Fang.
Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313220
► The reinforcement mechanism in WS2-based nanocomposites has been investigated in the project. It started with the deformation analysis on the micromechanical exfoliated WS2 (monolayer and…
(more)
▼ The reinforcement mechanism in WS2-based
nanocomposites has been investigated in the project. It started
with the deformation analysis on the micromechanical exfoliated WS2
(monolayer and fewlayer) and nanotube WS2 using photoluminescence
(monolayer only) and Raman spectroscopies. For monolayer, a massive
PL energy shift has been observed caused by uniaxial tensile strain
engineered optical bandgap. A new feature in the PL spectra
corresponding to the indirect band gap transition (Γ-T) has
emerged under moderate uniaxial stress level. In all cases,
significant Raman band shifts have been found for both E2g1 and A1g
modes due to strain-induced phonon softening. The E2g1 mode
undergoes splitting at high strain level, which was taken advantage
of to determine the crystalline orientation of exfoliated WS2. A
systematic study has been undertaken on the monolayer, bilayer,
trilayer and fewlayer WS2 under deformation to determine the
optimum the number of layers for reinforcement. An anomalous phonon
behavior for the thicker WS2 during deformation has been found and
addressed. By following the E2g1 mode and PL energy band, the
stress transfer in exfoliated WS2 has been examined in a model
composite under uniaxial strain. These behaviors have demonstrated
the WS2 can act as reinforcing phase in its nanocomposites and the
behavior can be predicted with shear lag theory. The study has also
suggested moderated interfacial bonding between the WS2 and polymer
matrix and given an implication of the use of WS2 for polymer
reinforcement. Finally, the bulk PVA nanocomposites reinforced by
liquid exfoliated WS2 were investigated to validate our finding
from the model composites. Significant increase in
Young’s modulus occurs at a very low WS2 loading. The
most effective reinforcement is brought by the incorporation of WS2
at 1.2 wt% fractions. The effective modulus of WS2 in the
composites was calculated by the rule of mixture. The interlayer
slippage of fewlayer WS2 has been found to be a significant factor
that compromises the reinforcing effect.
N\A
N\A
Advisors/Committee Members: YOUNG, ROBERT RJ, Kinloch, Ian, Young, Robert.
Subjects/Keywords: WS2; Raman; Photoluminescence; Polymer Nanocomposites
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, F. (2018). Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313220
Chicago Manual of Style (16th Edition):
Wang, Fang. “Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313220.
MLA Handbook (7th Edition):
Wang, Fang. “Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites.” 2018. Web. 20 Jun 2019.
Vancouver:
Wang F. Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313220.
Council of Science Editors:
Wang F. Raman and Photoluminescence Spectroscopic Studies of the
Micromechanics of WS2 Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:313220
University of Manchester
25.
Hick, Ralph.
Hierarchical Graphene Supercapacitors.
Degree: 2018, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:315472
► Electrochemical supercapacitors are promising devices for energy storage applications. However, their uptake is currently limited by their relatively low energy density. The recent discovery of…
(more)
▼ Electrochemical supercapacitors are promising
devices for energy storage applications. However, their uptake is
currently limited by their relatively low energy density. The
recent discovery of graphene has strengthened supercapacitor
research, due to graphene’s high surface area, conductivity,
strength, and flexibility. However, the synthesis of large
quantities of defect-free graphene and its subsequent incorporation
into supercapacitors has proved difficult due to aggregation and
restacking of the graphene. Hence, in order to retain the high
surface area of graphene, it needs to be incorporated into
hierarchical structures. Given these issues, this thesis aimed to
produce high quality graphene flakes via electrochemical
exfoliation. These flakes were then processed into hierarchical
structures (foams and fibres) for supercapacitor devices. The
graphene was exfoliated using a reductive process, with two
different cells designs explored. The influence of the
microstructure of the initial graphite on the exfoliation process
was also studied. The hierarchical foams were produced by
depositing the graphene onto nickel foam. It was found that the
degree of exfoliation has a marginal effect on the capacitance of
the device. This electrochemically exfoliated graphite was also
wet-spun with polyacrylonitrile (PAN) and carbonised to produce
carbon fibre-graphene composites. It was found that the carbonised
materials had a higher capacitance than the precursor material (33
F g-1 and 47 F g-1 respectively). As a comparison, wet-spun
graphene oxide fibres were synthesised with polyvinyl alcohol and
were subsequently carbonised and reduced. These fibres gave
comparable capacitance results to the carbonised polyacrylonitrile
fibres (47 F g-1 and 40 F g-1 respectively).
Advisors/Committee Members: DRYFE, ROBERT RAW, Kinloch, Ian, Dryfe, Robert.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hick, R. (2018). Hierarchical Graphene Supercapacitors. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:315472
Chicago Manual of Style (16th Edition):
Hick, Ralph. “Hierarchical Graphene Supercapacitors.” 2018. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:315472.
MLA Handbook (7th Edition):
Hick, Ralph. “Hierarchical Graphene Supercapacitors.” 2018. Web. 20 Jun 2019.
Vancouver:
Hick R. Hierarchical Graphene Supercapacitors. [Internet] [Doctoral dissertation]. University of Manchester; 2018. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:315472.
Council of Science Editors:
Hick R. Hierarchical Graphene Supercapacitors. [Doctoral Dissertation]. University of Manchester; 2018. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:315472
26.
Alshammari, Basheer.
Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites.
Degree: 2015, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:246461
► Incorporation of conductive carbon fillers into polymer matrices can improve electrical,thermal and mechanical properties of the resulting composites. In this work, three differentconductive carbon fillers…
(more)
▼ Incorporation of conductive carbon fillers into
polymer matrices can improve electrical,thermal and mechanical
properties of the resulting composites. In this work, three
differentconductive carbon fillers were used; i.e. graphite,
graphite nanoplatelets (GNP) and asreceivedmultiwall carbon
nanotubes (A-MWCNT). In addition, A-MWCNT were modifiedusing mixed
acids and named as T-MWCNT. These four fillers were incorporated
into poly(ethylene terephthalate) (PET) to prepare four types of
PET/carbon micro- and nanocomposites.These composites were prepared
by melt compounding using a Haake Minilabextruder equipped with a
co-rotating twin screws. The extruded samples were
compressionmoulded to films of 1 mm thickness and were subsequently
quenched to obtain lowcrystallinity samples. The extruded samples
were also injection moulded to obtain dumbbellshaped specimens. The
electrical, morphological, thermal and mechanical properties of
thesecomposites were studied and characterized as a function of
carbon filler types and contentsusing a wide range of analytical
and testing techniques: namely; impedance spectroscopy,DSC, TGA,
SEM, TEM, FTIR, DMTA and tensile testing. The results demonstrated
that theaddition of graphite, GNP and A-MWCNT produced electrically
conductive composites andthat the conductivities were found to be
dependent on several factors; including filler type,filler content
and processing conditions. The PET/A-MWCNT nanocomposites showed
anexcellent electrical conductivity (~ 0.2 S/m at 2 wt. % A-MWCNT)
with a low percolationthreshold (Fc ~ 0.33 wt. %). In contrast,
PET/T-MWCNT nanocomposites displayed similarelectrical conductivity
to that of pure PET and no percolation threshold was observed in
thiscase (until 2 wt. % of CNT), this was attributed to the acid
treatment which disrupted theinherent electrical conductivity of
the CNT and also reduced their aspect ratio. However, TMWCNTshowed
better dispersion and distribution into the PET matrix as well as
reducedCNT-CNT interactions and therefore do not as readily form
network structures. This resultedin better mechanical properties in
comparison to the PET/A-MWCNT nanocomposites. Interms of
processing, increasing screw speed during mixing was found to
enhance theelectrical conductivities of PET/carbon nanocomposites
(GNP and A-MWCNT), but onlyabove the percolation thresholds values,
by ~ 2 – 3 orders of magnitude. However, nosignificant change was
observed in the electrical conductivities of
PET/graphitemicrocomposites. All the carbon fillers, with different
dimensions, were found to act asnucleating agents for the PET
matrix and hence accelerated crystallization and increased
thedegree of crystallinity. CNT were found to accelerate the
crystallization at lower loadingscompared to GNP and graphite. In
addition, it was found that quenched PET and compositesamples were
not fully crystallized after processing and therefore (cold)
crystallized duringthe first heating cycle in both DSC and DMTA, as
indicated by crystallisation peaks duringthe DSC first-heat and a…
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
…composites
The University of Manchester
Basheer A. Alshammari
Doctor of Philosophy
18, September… …x28;the “Copyright”) and he has given The
University of Manchester certain rights to…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Alshammari, B. (2015). Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:246461
Chicago Manual of Style (16th Edition):
Alshammari, Basheer. “Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites.” 2015. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:246461.
MLA Handbook (7th Edition):
Alshammari, Basheer. “Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites.” 2015. Web. 20 Jun 2019.
Vancouver:
Alshammari B. Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites. [Internet] [Doctoral dissertation]. University of Manchester; 2015. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:246461.
Council of Science Editors:
Alshammari B. Processing, Structure and Properties of Poly
(ethyleneterephthalate)/Carbon Micro- and
Nano-composites. [Doctoral Dissertation]. University of Manchester; 2015. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:246461
27.
Gong, Lei.
Deformation Micromechanics of Graphene
Nanocomposites.
Degree: 2013, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:189695
► Graphene nanocomposites have been successfully prepared in this study in the form of a sandwich structure of PMMA/graphene/SU-8. It has been proved that Raman spectroscopy…
(more)
▼ Graphene nanocomposites have been successfully
prepared in this study in the form of a sandwich structure of
PMMA/graphene/SU-8. It has been proved that Raman spectroscopy is a
powerful technique in the characterisation of the structure and
deformation of graphene. The 2D band of the monolayer graphene has
been used in the investigation of stress transfer in the graphene
reinforced nanocomposites. It has been demonstrated that the 2D
band moves towards low frequency linearly under tensile stress,
which is shown to be significant method of monitoring the strain in
graphene in a deformed specimen. The Raman spectroscopy behaviour
under deformation validates that the monolayer graphene acts as a
reinforcing role in nanocomposites although it is only one atom
thick.A systematic investigation of the deformation of bilayer,
trilayer and few-layer graphene has been undertaken with a view to
determine the optimum number of layers for the reinforcement of
nanocomposites. It has been demonstrated that monolayer graphene is
not necessarily the optimum material to use for reinforcement in
graphene-based polymer nanocomposites and bilayer graphene will be
equally as good as monolayer graphene. There is therefore a balance
to be struck in the design of graphene-based nanocomposites between
the ability to achieve higher loadings of reinforcement and the
reduction in effective Young’s modulus of the reinforcement, as the
number of layers in the graphene is increased.Both the G and 2D
bands have been found to undergo splitting under high strain levels
or asymmetric band broadening in lower strain deformation. The G
band polarisation property has been utilized to determine the
crystallographic orientation of monolayer graphene by measuring the
intensity ratio of G-/G+ bands. Analogously, the 2D band also
undergoes strain-induced splitting where the 2D- band has higher
Raman shift rate than that of the 2D+ band.
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: Graphene; Graphene Nanocomposite; Raman; Strain
mapping; Reinforcement
…x28;the “Copyright”) and he has
given The University of Manchester certain rights to… …Novoselov of the University of Manchester,
Department of Physics and Astronomy)
The simplest…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gong, L. (2013). Deformation Micromechanics of Graphene
Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:189695
Chicago Manual of Style (16th Edition):
Gong, Lei. “Deformation Micromechanics of Graphene
Nanocomposites.” 2013. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:189695.
MLA Handbook (7th Edition):
Gong, Lei. “Deformation Micromechanics of Graphene
Nanocomposites.” 2013. Web. 20 Jun 2019.
Vancouver:
Gong L. Deformation Micromechanics of Graphene
Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2013. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:189695.
Council of Science Editors:
Gong L. Deformation Micromechanics of Graphene
Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2013. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:189695
28.
Jirakittidul, Kittimon.
Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites.
Degree: 2013, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:211995
► In this research work, the relationships between structure and properties in micro-composites and nano-composites of polyurethane (PU) and conductive carbon particles have been studied. PU…
(more)
▼ In this research work, the relationships between
structure and properties in micro-composites and nano-composites of
polyurethane (PU) and conductive carbon particles have been
studied. PU is a class of block copolymers containing the urethane
linkage (-NHCO-O-) within its structure. Most PU block copolymers
consist of alternating ‘soft’ and ‘hard’ segments. The hard segment
used in this study was based on 4,4’-methylenebisphenylisocyanate
(MDI) and 2-methyl 1,3 propanediol (MP-Diol) which produced a stiff
aromatic polyurethane. Two soft segments; poly(tetrahydofuran)
(PTHF) and poly(propylene oxide) based polyol end-capped with
ethylene oxide (PPO-EO) were used to study the effects of soft
segment structure on PU properties. DMTA, DSC and modulated-DSC
indicated that PU-PTHF had higher microphase separation due to
greater immiscibility between PTHF and the MDI/MP-Diol hard
segments. In order to improve the electrical and mechanical
properties of PU, conductive carbon particles were incorporated.
The critical factor was the dispersion of these conductive fillers
in the PU matrix to obtain optimum properties. The first carbon
filler studied was carbon black (CB). PU composites prepared by the
adding of MP-Diol plus ultrasonication (MU) gave the best
dispersion of CB aggregates resulting in higher thermal
decomposition temperature and good conductivity. However, the
mechanical toughness was reduced. In subsequent studies, PU
composites incorporating three different treated multiwalled carbon
nanotubes (MWCNT) were investigated. MWCNT were disentangled and
shortened by ultrasonication and acid cutting treatments. The
ultrasonicated MWCNT (MWCNT_U) had longer length than the acid-cut
MWCNT (MWCNT_AC). Ultrasonication was the best technique for
dispersing MWCNT since the storage modulus was increased by ~200%
at low MWCNT_U loading and the toughness remained the same as
unfilled PU. PU/MWCNT_AC nanocomposites at 1 – 3 wt% of MWCNT_AC
exhibited similar electrical conductivities to unfilled PU at an
order of 10-8 S/cm, implying that the acid cutting treatment might
disturb the inherent conductivity in MWCNT. The conductive
percolation thresholds of composites were determined following the
percolation theory. It was found that the percolation thresholds
for MWCNT-filled composites were significantly lower than that of
CB-filled composites. The lowest percolation threshold was observed
in MWCNT_U-filled composite at 0.31 wt%.
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
Subjects/Keywords: Polyurethane; Nanocomposite; Carbon black; Carbon nanotube
…University of Manchester
Kittimon Jirakittidul
Structure-Property Relationships in Polyurethane… …x29; and s/he has
given The University of Manchester certain rights to use such Copyright…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Jirakittidul, K. (2013). Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:211995
Chicago Manual of Style (16th Edition):
Jirakittidul, Kittimon. “Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites.” 2013. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:211995.
MLA Handbook (7th Edition):
Jirakittidul, Kittimon. “Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites.” 2013. Web. 20 Jun 2019.
Vancouver:
Jirakittidul K. Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2013. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:211995.
Council of Science Editors:
Jirakittidul K. Structure-Property Relationships in Polyurethane-Carbon
Particle Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2013. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:211995
29.
Othman, Raja.
Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles.
Degree: 2012, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:181296
► Carbon nanotubes (CNTs) have been successfully grafted onto the surfaces of spherical silica gels via a floating-catalyst chemical vapour deposition method. Two types of silica…
(more)
▼ Carbon nanotubes (CNTs) have been successfully
grafted onto the surfaces of spherical silica gels via a
floating-catalyst chemical vapour deposition method. Two types of
silica gels were used as substrates; SG6 (6 – 8 nm pore size) and
SG26 (26 – 34 nm pore size). The optimum growth conditions were
found to be 760 °C growth temperature, 3 hours growth time, and 5
wt .% of ferrocene catalyst (dissolved in toluene) injected into
the furnace at a rate of 0.04 ml/min. Under these conditions, CNTs
coated the exterior surface of the gels with growth occurring from
both the pores and from the surface. The geometry and porosity of
the silica gel were also found to influence the alignment and
density of the grafted CNTs, with SG6 producing the best quality
hybrid particle under the above conditions (labelled SG6_3).
Thermal Gravimetric Analysis showed the yield of CNTs grown under
these optimum condition was 33.6 + 0.37 wt. %. As the CNTs remained
strongly attached to the surface of the gel, the grafting process
produced excellent dispersion of the CNTs within polymer matrices
as CNT bundle formation was prevented. The inclusion of micron size
silica introduced a large excluded volume within polymer matrices,
with the dispersion of CNTs restricted to a region along the silica
surface. This arrangement aided the formation of an electrically
conductive network in a poly (vinyl) alcohol matrix, where the
critical percolation threshold (pc) was calculated as 0.62 wt. % of
SG6_3, equivalent to a CNT content of 0.2 wt. %.The inclusion of
SG6_3 into an epoxy resin suspension did not alter the rheological
behaviour of the resin up to the highest loading employed (5 wt. %,
≈1.65 wt. % of CNTs). Within the linear viscoelastic region the
viscoelastic moduli of the neat resin remained within the same
magnitude, whilst the addition of 1.65 wt. % of commercially
available CNTs into the same resin increased the storage and loss
moduli by up to seven and three orders of magnitude, respectively.
The complex viscosity of the suspension remained unchanged
regardless of the amount of SG6_3 added; whereas an increase in
viscosity of up to five orders of magnitude resulted from the
addition of 1.65 wt. % non – grafted CNTs.Grafting of CNTs onto the
surface of micron size spherical silica gel has been shown to
provide a means of incorporating CNTs into a polymer without
increasing viscosity. In addition, the SG6_3 also formed an
electrically-conductive percolated network in an epoxy resin
composite at low levels of addition, with pc = 0.16 wt. % of CNTs
(i.e. 0.5 wt. % SG6_3).
Advisors/Committee Members: KINLOCH, IAN IA, Wilkinson, Arthur, Kinloch, Ian.
Subjects/Keywords: Rheology; Carbon Nanotube; Impedance
…18
Abstract
The University of Manchester
Raja Nor Raja Othman
Doctor of Philosophy… …of Manchester certain rights to use such Copyright, including for
administrative purposes… …copyright ore related rights in it (the “Copyright”) and s/he has given
The University…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Othman, R. (2012). Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:181296
Chicago Manual of Style (16th Edition):
Othman, Raja. “Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles.” 2012. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:181296.
MLA Handbook (7th Edition):
Othman, Raja. “Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles.” 2012. Web. 20 Jun 2019.
Vancouver:
Othman R. Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:181296.
Council of Science Editors:
Othman R. Synthesis and Characterisation of Hybrid Carbon -
Nanotube Silica Microparticles. [Doctoral Dissertation]. University of Manchester; 2012. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:181296
30.
Wafy, Tamer.
Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites.
Degree: 2013, University of Manchester
URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:188012
► Characterization of Chemical and Mechanical Properties of Polymer Based NanocompositesThe University of ManchesterTamer Wafy Doctor of Philosophy17 January, 2013One of the most significant issues in…
(more)
▼ Characterization of Chemical and Mechanical
Properties of Polymer Based NanocompositesThe
University of
ManchesterTamer Wafy Doctor of Philosophy17 January, 2013One of the
most significant issues in nanocomposite performance is improving
the dispersion of carbon nanotubes (CNTs) in thermosetting or
thermoplastic polymers in order to gain good mechanical properties.
Several studies have investigated the fabrication of nanocomposites
based on carbon nanotubes and analysed properties, but there is
still insufficient data on their structure-property relationships.
This thesis has investigated the central importance of stress
transfer Raman studies in epoxy composites reinforced with
single-walled carbon nanotubes (SWCNTs), double-walled carbon
nanotubes (DWCNTs) and multiwall carbon nanotubes (MWCNTs) to
elucidate the reinforcing ability of the CNTs in an epoxy matrix.
This project was undertaken to synthesise and characterize MWCNTs
and determine the effect of different weight fractions of untreated
MWCNTs on the stress transfer efficiency at the MWCNTS / epoxy
interface and on the stiffness of the thermomechanical properties
of the MWCNTS / epoxy composites. It was undertaken to assess the
stress transfer efficiency at the CNT / epoxy interface and at the
inter-walls of the CNTs with tensile deformation and with cyclic
loading.Optimized conditions of the injection chemical vapour
deposition method (CVD), such as long injection times were applied
to produce MWCNTs with a high yield, high aspect ratio and
well-defined G' Raman peak. The morphology and size of CNTs were
observed by scanning electron microscopy (SEM) and transmission
electron microscopy (TEM) while their thermal stability was
examined by Thermogravimetric analysis (TGA). Both Raman
spectroscopy and mechanical testing (static and dynamic) were
utilized in this study. The Raman spectroscopy research consisted
of following the G'-band frequency and linewidth as well as the
intensity of radial breathing modes (RBMs) during tensile
deformation. The stress-induced Raman shifts in the nanocomposites
have been shown to be controlled by the number of carbon
nanolayers. A theory has been developed to determine and simulate
the stress transfer efficiency parameter, (k_i) for MWCNTs. Tensile
tests and dynamic mechanical testing were used to assess the
mechanical properties of the nanocomposites.The most obvious
finding to be drawn from the present study is that the
reinforcement of the epoxy resin with different loadings of MWCNTs
is useful, but the best reinforcement was at low loadings of
MWCNTs. One of the more significant findings to emerge from this
study is that (k_i) between the inner walls of the DWCNTs and
MWCNTs are quite similar (~0.7), which suggest that (k_i) may be
similar for all CVD MWCNTs and DWCNTs. The second major finding was
that there were RBM intensity variations for the SWCNTs and DWCNTs
in the hot-cured epoxy composites and that for the DWCNTs both the
inner and outer nanotube walls are stressed during
deformation
Advisors/Committee Members: KINLOCH, IAN IA, Young, Robert, Kinloch, Ian.
Subjects/Keywords: Single-walled carbon nanotubes (SWCNTs); Double-walled carbon nanotubes (DWCNTs); Multiwall carbon nanotubes (MWCNTs); Graphene; Stress transfer; Raman spectroscopy; Epoxy nanocomposites; Mechanical properties; G' Raman peak
…of Polymer Based
Nanocomposites
The University of Manchester
Tamer Wafy
Doctor of…
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wafy, T. (2013). Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:188012
Chicago Manual of Style (16th Edition):
Wafy, Tamer. “Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites.” 2013. Doctoral Dissertation, University of Manchester. Accessed June 20, 2019.
http://www.manchester.ac.uk/escholar/uk-ac-man-scw:188012.
MLA Handbook (7th Edition):
Wafy, Tamer. “Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites.” 2013. Web. 20 Jun 2019.
Vancouver:
Wafy T. Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites. [Internet] [Doctoral dissertation]. University of Manchester; 2013. [cited 2019 Jun 20].
Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:188012.
Council of Science Editors:
Wafy T. Characterization of Chemical and Mechanical Properties of
Polymer Based Nanocomposites. [Doctoral Dissertation]. University of Manchester; 2013. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:188012
◁ [1] [2] ▶
. 
Open Access Theses and Dissertations
