subject:(transition metal oxides)

Cornell University

1. Asenath Smith, Emily. Bio-Inspired Crystallization Of Oxides In Inorganic Matrices.

Degree: PhD, Materials Science and Engineering, 2015, Cornell University

► The energy crisis facing our planet requires solutions that take an interdisciplinary approach to the improvement of existing energy systems as well as the development… (more)

▼ The energy crisis facing our planet requires solutions that take an interdisciplinary approach to the improvement of existing energy systems as well as the development of new energy sources. Moreover, the composition of the materials is important: thermally- and chemically-stable materials based on abundant, non-toxic elements are needed to support the sustainability of both the technology and our environment. Biological organisms present multiple examples of hierarchical structures that are optimized for a given function. In particular, biomineralized materials: (i) display crystallographic control across length scales; (ii) are often organic-inorganic composites due to the occlusion of components from the associated organic growth matrix; (iii) and exhibit tailored mechanical properties that are unique to their function. Of great importance to the development of advanced energy materials is the observation that biomineral architectures are built from crystallographically-defined structural elements with interfaces that span multiple length scales. Synthetically, the translation of biological mineralization strategies to oxide compounds is hindered by the low melting temperatures of biopolymer hydrogels that compose extracellular matrices. In order to successfully crystallize oxide compounds using a (bio-inspired) matrix-mediated approach, I had to identify and develop a hydrogel system with thermal stability and chemical compatibility to the growth conditions needed for the oxide. By moving to inorganic networks based on silica, I achieved a thermally-stable growth matrix. By forming these networks at low pH, I obtained a growth environment that was compatible with the crystallization of hematite. With these two features, hematite was crystallized under diffusion-limited conditions, which provided a means to to manipulate its structure and assembly from the atomic- to the microscale. By combining inductively coupled plasma atomic emission spectroscopy with Rietveld refinements to x-ray diffraction data, expansion of the hematite lattice along the c-axis was found to be correlated to increasing silicon in the crystals and the preferential growth of the coherent domains along [110] (perpendicular to the strained c-axis). Using single particle manipulation in a focused ion beam system, electron-transparent thin sections were prepared from precisely-defined geometric locations within the hematite crystals for analysis by transmission electron microscopy. Quantitative analysis on selected area electron diffraction patterns was used to unravel the net orientation of the hematite lattice with respect to the quasi-spherical form and to calculate the misorientation (mosaicity) between the coherent domains. The combined results of these analyses showed that silicon from the growth environment had consistently modified the architecture of hematite, from the atomic to the microscale, leading to microscale structures with surfaces composed of nanoscale, high catalytic activity {110} facets. With hydrogel growth as a… Advisors/Committee Members: Estroff,Lara A. (chair), Disalvo,Francis J (committee member), Gruner,Sol Michael (committee member).

Subjects/Keywords: Biomineralization; Crystallization; Transition Metal Oxides

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APA (6^th Edition):

Asenath Smith, E. (2015). Bio-Inspired Crystallization Of Oxides In Inorganic Matrices. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/40624

Chicago Manual of Style (16^th Edition):

Asenath Smith, Emily. “Bio-Inspired Crystallization Of Oxides In Inorganic Matrices.” 2015. Doctoral Dissertation, Cornell University. Accessed January 24, 2021. http://hdl.handle.net/1813/40624.

MLA Handbook (7^th Edition):

Asenath Smith, Emily. “Bio-Inspired Crystallization Of Oxides In Inorganic Matrices.” 2015. Web. 24 Jan 2021.

Vancouver:

Asenath Smith E. Bio-Inspired Crystallization Of Oxides In Inorganic Matrices. [Internet] [Doctoral dissertation]. Cornell University; 2015. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1813/40624.

Council of Science Editors:

Asenath Smith E. Bio-Inspired Crystallization Of Oxides In Inorganic Matrices. [Doctoral Dissertation]. Cornell University; 2015. Available from: http://hdl.handle.net/1813/40624

Rutgers University

2. Gardner, Graeme Patrick, 1988-. Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides.

Degree: PhD, Chemistry and Chemical Biology, 2016, Rutgers University

URL: https://rucore.libraries.rutgers.edu/rutgers-lib/51292/

► Transition metal oxides and related nitrides/nitride-oxides represent a class of materials that have shown great promise as oxygen electrocatalysts to replace the otherwise non-scalable noble… (more)

▼ Transition metal oxides and related nitrides/nitride-oxides represent a class of materials that have shown great promise as oxygen electrocatalysts to replace the otherwise non-scalable noble metal-based catalysts currently implemented in commercial technologies. That is, compounds in this class of materials have shown promise as electrocatalysts for both the oxygen evolution (OER) and oxygen reduction reactions (ORR). The two aforementioned half-reactions are at the cornerstone of most renewable energy transformations, as oxygen is an inherently practical and abundant source and sink for electrons. In water electrolysis to produce hydrogen, oxygen is inevitably formed, and in a fuel cell the driving force for extracting electrochemical energy from hydrogen is pairing it with the reduction of oxygen to water. If this can be accomplished reversibly, the problem of "transient" renewable energy and its storage can be mitigated. We have examined many metal oxides and related compounds based upon Earth- abundant transition metals (primarily first row) that are crystalline, yet high surface area, for these important electrocatalytic reactions, and found that crystal structure plays a crucial role in determining activity. In fact, while most studies on heterogeneous catalysis focus on the synthesis of defect-rich, high surface area, practically amorphous materials to elicit high activity, we have found that particular crystalline phases possess not only the appropriate activity, but to some degree more importantly, the stability to be named good catalysts. In Chapter 2, we demonstrate that of the two structural types of lithium cobalt oxide (LiCoO2) - layered (R-3m) and cubic (Fd-3m) - only the cubic phase is revealed to be an efficient and stable catalyst for OER. Whether water oxidation is driven photochemically, or electrochemically, the cubic phase LiCoO2 possessing a spinel-like structure (AB2O4) with [Co4O4] subunits within the crystal is more active. It is seen that electrochemically, both the cubic and layered phases transform to the spinel LiCo2O4 at surface and subsurface levels. This coincides with partial delithiation that is more extensive in layered LiCoO2. It is revealed that the oxidation of Co3+ to Co4+ is accompanied by delithiation in aqueous electrolyte to form the active state of the LiCoO2 catalyst. The electronic properties of the cubic spinel allow for localization of electron holes at cubic core active sites to effect water oxidation, whereas holes are more extensively delocalized in layered LiCoO2 in concert with the Li+ deintercalation reaction. In Chapter 3, we investigate the influence of chemical composition on the catalytic water oxidation activity of Co-substituted spinel LiMn2O4 and Mn-substituted cubic LiCoO2. We find that in the spinel LiMn2O4, Co3+ substitution occurs at the B-site for Mn3+, and the solid solution limit for starts at 1:1 Co:Mn ratio, where Co begins to go into the A-site. The activity for OER increases with increasing Co, owing to the symmetrization of the M4O4 core… Advisors/Committee Members: Dismukes, Gerard Charles (chair), Castner, Edward W. (internal member), Greenblatt, Martha (internal member), Amatucci, Glenn G (outside member).

Subjects/Keywords: Transition metal oxides; Catalysts

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APA (6^th Edition):

Gardner, Graeme Patrick, 1. (2016). Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/51292/

Chicago Manual of Style (16^th Edition):

Gardner, Graeme Patrick, 1988-. “Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides.” 2016. Doctoral Dissertation, Rutgers University. Accessed January 24, 2021. https://rucore.libraries.rutgers.edu/rutgers-lib/51292/.

MLA Handbook (7^th Edition):

Gardner, Graeme Patrick, 1988-. “Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides.” 2016. Web. 24 Jan 2021.

Vancouver:

Gardner, Graeme Patrick 1. Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides. [Internet] [Doctoral dissertation]. Rutgers University; 2016. [cited 2021 Jan 24]. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/51292/.

Council of Science Editors:

Gardner, Graeme Patrick 1. Structural implications for oxygen electrocatalysis in Earth-abundant transition metal oxides. [Doctoral Dissertation]. Rutgers University; 2016. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/51292/

Oregon State University

3. Gatimu, Alvin J. Structure-property relationships in oxides containing select platinum group metals.

Degree: PhD, Chemistry, 2012, Oregon State University

URL: http://hdl.handle.net/1957/31770

► Oxide materials exhibit a wide variety of structures and properties. In particular, transition metal oxides tend to be highly stable while exhibiting a wide range… (more)

▼ Oxide materials exhibit a wide variety of structures and properties. In particular, transition metal oxides tend to be highly stable while exhibiting a wide range of properties that can be used for numerous applications. This work focuses on investigating how the structures’ of 4d and 5d transition metal oxides influences their properties. Specifically oxides of Ru, Rh and Ir were investigated. A complete solid solution was found between isostructural Pb₃Mn₇O₁₅ and Pb₃Rh₇O₁₅. Pb₃Rh₇O₁₅ shows a Verwey-type transition at 185 K. This transition remains with a 3 % substitution of Mn for Rh but disappears with a 4 % substitution of Mn for Rh. The structure was found to expand in the direction perpendicular to the layers of the structure, which is the c-axis, despite a contracting unit cell. Bi for Pb substitution in Pb₃Mn₇O₁₅ was found to be limited as compared to in Pb₃Rh₇O₁₅. Alkali metal substitution on the A-site of the orthorhombic perovskite SrRuO₃ showed only low substitution levels were possible. Nonetheless, the substituted phases showed decreased ferromagnetic Curie temperatures, increased electrical resisitivity and relatively unchanged Seebeck coefficients. Thermoelectric studies of Sr[subscript 2-x]La[subscript x]CoRuO₆ perovskite phases showed Sr₁.₁La₀.₉CoRuO₆ with the best thermoelectric performance. This system showed possible correlations between cation ordering on the B-site and the charge carrier transport. A similar thermoelectric study of (RhV)[subscript 1+x]Ti[subscript 1-2x]O₆ phases crystallizing in a disordered trirutile structure was done. Electron carriers were found to be dominant and dependent on Ti content. The electron carriers appear to become diminished at higher temperatures. Sr₂IrO₄ crystallizes in a K₂NiF₄-type structure. Effects of Ti, Fe and Co substitution for Ir were investigated. A complete Sr₂Ir[subscript 1-x]Ti[subscript x]O₄ solid solution was synthesized and characterized while limited solubility was found for Fe and Co substitutions. All substitutions showed a decrease in the c-cell parameter coupled with a decrease in octahedral tilting. All substitutions also showed a decrease in magnetic susceptibility and an increase in the paramagnetic effective moment was observed for Co and Fe doped samples. An incomplete solid solution was formed for Sr₂Ti[subscript 1-x]Rh[subscript x]O₄ phases; however effects of increased octahedral tilting with higher Rh content were observed. Advisors/Committee Members: Subramanian, Munirpallam A. (advisor), Sleight, Arthur W. (committee member).

Subjects/Keywords: Oxides; Transition metal oxides – Structure-activity relationships

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gatimu, A. J. (2012). Structure-property relationships in oxides containing select platinum group metals. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/31770

Chicago Manual of Style (16^th Edition):

Gatimu, Alvin J. “Structure-property relationships in oxides containing select platinum group metals.” 2012. Doctoral Dissertation, Oregon State University. Accessed January 24, 2021. http://hdl.handle.net/1957/31770.

MLA Handbook (7^th Edition):

Gatimu, Alvin J. “Structure-property relationships in oxides containing select platinum group metals.” 2012. Web. 24 Jan 2021.

Vancouver:

Gatimu AJ. Structure-property relationships in oxides containing select platinum group metals. [Internet] [Doctoral dissertation]. Oregon State University; 2012. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1957/31770.

Council of Science Editors:

Gatimu AJ. Structure-property relationships in oxides containing select platinum group metals. [Doctoral Dissertation]. Oregon State University; 2012. Available from: http://hdl.handle.net/1957/31770

Oregon State University

4. Smith, Andrew E. (Andrew Earnest). Functional transition metal oxides : structure-property relationships.

Degree: PhD, Chemistry, 2010, Oregon State University

URL: http://hdl.handle.net/1957/16293

► Transition metal oxides are an important class of materials for the wide variety optical, electrical, dielectric, magnetic, and thermal properties observed. Their unique structure-property relationships… (more)

▼ Transition metal oxides are an important class of materials for the wide variety optical, electrical, dielectric, magnetic, and thermal properties observed. Their unique structure-property relationships allow for property tuning and often provide insight into the fundamentals of chemistry. The work in this thesis was focused on the design, synthesis and physical property characterization of novel materials with applications in mind. In particular, magneto-electric multiferroics and spintronics are a promising technology for applications in many areas of electronics where either the magnetic or electric properties can be manipulated with electric or magnetic fields respectively. La₂MnRhO₆ thin films were found to exhibit a change in the defect structure, surface morphology, and magnetic properties for films grown at different oxygen pressures revealing the importance of deposition methods. Bulk ceramic of La₂MRhO₆ (M = Cr, Mn, Fe, Co, Ni and Cu) were characterized and all were found to be orthorhombic p-type semiconductors. Unique magnetism was found for M = Fe and Cr with both showing magnetic hysteresis at 5K. The Cu analogue is likely to be in a 2+/3+ oxidation state, and showed a favorable power factor up to ~575 K. LaCo[subscript 1-x]Rh[subscript x]O₃ compositions were found to exhibit an interesting lattice crossover at x = 0.5. Strong evidence for at least some conversion of Rh³⁺/Co³⁺ to Rh⁴⁺/Co²⁺ is found in both structural and electrical transport data. A thermoelectric figure-of-merit (ZT) of about 0.075 has been achieved for LaCo₀.₅Rh₀.₅O₃ at 775 K YMnO₃ is a well known magneto-electric material, and in our study, we have prepared complete or nearly complete solid solutions with YInO₃, YAlO₃, and YCu₀.₅Ti₀.₅O₃ systems in order to better understand the structure-property relationships. Our results indicate exciting optical properties as a wide range of blue was observed in the YInO₃ solid solution, the intensity of which was critically dependent on the apical bond distances and the crystal field splitting. The YInO₃ and YCu₀.₅Ti₀.₅O₃ systems showed magnetic and magneto-electric suppression for increasing values as expected, but the field dependent capacitance for YInO₃ showed a unique improvement and sign swap indicating a strong magneto-electric coupling. We determined the YAlO₃ structure to have been improperly reported based on bond valence calculations. Our investigation into the YAlO₃-YMnO₃ system is underway, however we believe a carbonate group exists within the basal plane resulting in a chemical formula such as YAl[subscript 1-x]Mn[subscript x]O[subscript 3-y](CO₃)[subscript y]. For the high-k dielectric CaCu[subscript 3-x]Mn[subscript x]Ti[subscript 4-y]Fe[subscript y]O₁₂ and CaCu₃Ti₄O[subscript 12-x]F[subscript x], the limits of x, y were determined. A structural study on ceramic samples determined single phase materials, and dielectric measurements showed improvement of properties for fluorinated samples with the dielectric loss lowered while maintaining a high dielectric constant. It… Advisors/Committee Members: Subramanian, Mas (advisor), Sleight, Arthur W. (committee member).

Subjects/Keywords: Oxides; Transition metal oxides – Structure-activity relationships

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Smith, A. E. (. E. (2010). Functional transition metal oxides : structure-property relationships. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/16293

Chicago Manual of Style (16^th Edition):

Smith, Andrew E (Andrew Earnest). “Functional transition metal oxides : structure-property relationships.” 2010. Doctoral Dissertation, Oregon State University. Accessed January 24, 2021. http://hdl.handle.net/1957/16293.

MLA Handbook (7^th Edition):

Smith, Andrew E (Andrew Earnest). “Functional transition metal oxides : structure-property relationships.” 2010. Web. 24 Jan 2021.

Vancouver:

Smith AE(E. Functional transition metal oxides : structure-property relationships. [Internet] [Doctoral dissertation]. Oregon State University; 2010. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1957/16293.

Council of Science Editors:

Smith AE(E. Functional transition metal oxides : structure-property relationships. [Doctoral Dissertation]. Oregon State University; 2010. Available from: http://hdl.handle.net/1957/16293

Texas State University – San Marcos

5. Petersen, John E. Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions.

Degree: PhD, Materials Science, Engineering, and Commercialization, 2017, Texas State University – San Marcos

URL: https://digital.library.txstate.edu/handle/10877/6921

► The study of antiferromagnetic transition-metal oxides is an extremely active area in the physical sciences, where condensed matter physics, inorganic chemistry, and materials science blend… (more)

▼ The study of antiferromagnetic transition-metal oxides is an extremely active area in the physical sciences, where condensed matter physics, inorganic chemistry, and materials science blend together. The sheer number of potential commercial applications is staggering, but much of the fundamental science remains unexplained. This is not due to a lack of effort, however, as theorists have been struggling to understand these materials for decades – particularly the character of the band edges and first optical transitions. The difficulty lies in the strong correlation or Coloumb attraction between the electrons in the anisotropic d orbitals, which conventional band theory cannot describe adequately. The correlation problem is approached here by the well-accepted method of adding a Hubbard potential energy term to the ground state Hamiltonian, calculated within Density Functional Theory. The frequency-dependent complex dielectric function is calculated within the Independent Particle Approximation, and optical transitions are evaluated in multiple different ways. Peaks in the imaginary part of the dielectric function are compared energetically to orbitally decomposed density of states calculations. Optical transitions are typically analyzed in terms of atomic orbitals, which, strictly speaking, gives misleading results. Here, however, from the calculated data, two alternative interpretations are analyzed for each material studied. The first employs rigorous group theoretical analysis to determine allowed electric-dipole transitions, taking into account both orbital hybridization and crystal symmetry. The second interpretation is that of metal cation site hopping. In this interpretation, carriers hop from the x2 – y2 d orbital of one metal cation lattice site to the next metal cation site which is antiferromagnetically aligned. At times, thoughout this work, one interpretation is favorable to the other. Which interpretation is most valid depends on the material considered. For example, simple rock-salt transition-metal oxides are quite different from the high temperature superconducting cuprates. A range of materials is studied here, in order to gain a greater understanding of optical transitions in highly-correlated systems. In this work, O vacancies are introduced in NiO, along with Fe impurities, to understand better the band filling in the insulating behavior observed experimentally. These results are compared with those of La2NiO4, La2CuO4, La2-xSrxNiO4, and La2-xSrxCuO4. to elucidate the mechanisms behind the symmetry breaking phenomena in the Sr doped systems. As it turns out, indeed, the x2 – y2 orbital in these materials plays a critical role in spatial charge distribution, magnetic, and spin densities which are coupled to the dopant position in the lattice. The in-depth study of electronic and optical properties of transition-metal oxides presented here provides theoretical characterization of the infamous pseudogap in the cuprates – one of the greatest mysteries of modern solid state physics. In addition, via… Advisors/Committee Members: Myers, Thomas (advisor), Scolfaro, Luisa (advisor), Geerts, Wilhelmus (committee member), Droopad, Ravi (committee member), Martin, Benjamin (committee member), Temponi, Cecilia (committee member).

Subjects/Keywords: Transition-metal oxides; Optical properties; Transition metal oxides; Solid state physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Petersen, J. E. (2017). Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions. (Doctoral Dissertation). Texas State University – San Marcos. Retrieved from https://digital.library.txstate.edu/handle/10877/6921

Chicago Manual of Style (16^th Edition):

Petersen, John E. “Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions.” 2017. Doctoral Dissertation, Texas State University – San Marcos. Accessed January 24, 2021. https://digital.library.txstate.edu/handle/10877/6921.

MLA Handbook (7^th Edition):

Petersen, John E. “Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions.” 2017. Web. 24 Jan 2021.

Vancouver:

Petersen JE. Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions. [Internet] [Doctoral dissertation]. Texas State University – San Marcos; 2017. [cited 2021 Jan 24]. Available from: https://digital.library.txstate.edu/handle/10877/6921.

Council of Science Editors:

Petersen JE. Impurities In Antiferromagnetic Transition-metal Oxides – Symmetry And Optical Transitions. [Doctoral Dissertation]. Texas State University – San Marcos; 2017. Available from: https://digital.library.txstate.edu/handle/10877/6921

6. Patil, Amit Limbraj. Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion.

Degree: Chemistry, 2013, Shri Jagdishprasad Jhabarmal Tibarewala University

URL: http://shodhganga.inflibnet.ac.in/handle/10603/13455

►

Glass is an amorphous solid material. Glasses are typically brittle and optically transparent understanding the relationship between glass composition thermal history, handing and properties of… (more)

▼

Glass is an amorphous solid material. Glasses are typically brittle and optically transparent understanding the relationship between glass composition thermal history, handing and properties of the glass is essential for the production of reproducible high quality products with exact desired properties for a given application. Glass is commonly defined as an inorganic product of fusion, which is cooled to a rigid condition without crystallizing. However, more generally glass can be defined as an amorphous solid, completely lacking in long range periodic atomic structure and exhibiting a region of glass transformation behavior. In the widest sense, substance that solidifies from the liquid state without crystallization is known as glass physically glass is regarded as an amorphous, transparent or Semitransparent, super cooled liquid of infinite viscosity. The presence of glasses in our everyday life is so common that we rarely notice their existence. Early Egyptians considered glasses as precious materials, as evidenced by the glass beads found in the tombs and golden death masks of ancient pharaohs. The cave-dwellers of even earlier times relled on chipped pieces of obsidian, a natural volcanic glass, for tools and weapons. The ancient Egyptians possibly knew glass making 6000 years ago. The temple of Belus was constructed with bricks colour with glass enamel in Egypt about 2000 years ago. After words, Alexandria became the centre of glass industry and the knowledge of glass manufacture passed from the East to Greece and Europe In the first century B.C. Romans established a few glass factories in their country. England, France Germany started glass making in 15th and 16th century. The first scientific glass was prepared in 1854 by Germans in Jena. Possibly the production of glass owes its beginning to an accident. An illustration of such possibility is described by Velain. The glass was formed by the burning of grain and the fusion of the ash, as a result of fire caused by lightning.

Summary p. 169-176, References included

Advisors/Committee Members: Chanshetti, U B.

Subjects/Keywords: Chemistry; Alkali oxides; Transition metal-ion

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APA (6^th Edition):

Patil, A. L. (2013). Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion. (Thesis). Shri Jagdishprasad Jhabarmal Tibarewala University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/13455

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Patil, Amit Limbraj. “Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion.” 2013. Thesis, Shri Jagdishprasad Jhabarmal Tibarewala University. Accessed January 24, 2021. http://shodhganga.inflibnet.ac.in/handle/10603/13455.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Patil, Amit Limbraj. “Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion.” 2013. Web. 24 Jan 2021.

Vancouver:

Patil AL. Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion. [Internet] [Thesis]. Shri Jagdishprasad Jhabarmal Tibarewala University; 2013. [cited 2021 Jan 24]. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/13455.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Patil AL. Studies of synthesis and characterization of borate glass containing alkali oxides and transition metal ion. [Thesis]. Shri Jagdishprasad Jhabarmal Tibarewala University; 2013. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/13455

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Wollongong

7. Lu, Lin. Transition-metal oxides, sulphide and sulphur composites for lithium batteries.

Degree: Doctor of Philosophy, 2012, University of Wollongong

URL: 0912 MATERIALS ENGINEERING ; https://ro.uow.edu.au/theses/3872

► Lithium batteries are important energy storage systems and can make energy storage and usage more efficient than with previous solutions. Moreover, among the lithium… (more)

▼ Lithium batteries are important energy storage systems and can make energy storage and usage more efficient than with previous solutions. Moreover, among the lithium batteries, lithium-sulphur batteries are the next generation lithium battery that has the highest theoretical specific capacity (3860 mAh g-1) and the lowest gravimetric energy density. The applications of lithium-ion or lithium-sulphur batteries in electric vehicles, (plug-in) hybrid electric vehicles, or energy storage systems in smart grids require the battery to exhibit high rate capability, high power, and long cycle life. The key aspect for improving the performance of lithium-ion and lithium-sulphur batteries is to improve the performance of the active materials. The use of nanostructured materials and conductive composite materials is designed to enhance both ion transport and electron transport by shortening the diffusion lengths of ions (such as, Li+, Na+, K+, H+, and OH-) and increasing the conductivity within the electrode materials, respectively. In this doctoral work, several nanostructured materials and conductive (carbon or conducting polymer) composites were examined and characterized for possible application as electrode materials for lithium-ion batteries or lithium-sulphur batteries. For the Li-ion battery, nanocrystalline Fe3O4/C as anode material, nanostructured CuFeO2 as anode material, transition metal oxide/carbon composite anode, and ionic liquid electrolyte were investigated. Furthermore, MoS2 − carbon nanotube (CNT) composite thin film made from layered MoS2 was investigated for a lithium-ion thin film battery. Meanwhile, conducting polymer coated sulphur-CNT composites and sulphur-graphene composite for lithium-sulphur batteries were studied. Anode materials for lithium-ion battery: Synthesis of nanocrystalline Fe3O4 by the sol-gel method with in situ carbon coating was conducted. Carbon coating on Fe3O4 nanoparticles can be formed in situ by solgel methods using suitable precursor materials and/or solvents. The physical and electrochemical characterizations were carried out on the synthesized Fe3O4/C composite and bare Fe3O4. CuFeO2 has been synthesised in nanostructured form using a simple sol-gel method. This technique does not require any high cost precursors and produces powders with particle sizes of less than 1 μm. The cycle life and the high rate capability of nanostructured CuFeO2 have been studied in detail for the first time. To study the compatibility of transition metal oxide/carbon composite…

Subjects/Keywords: Lithium batteries; transition-metal oxides; sulphide; sulphur

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lu, L. (2012). Transition-metal oxides, sulphide and sulphur composites for lithium batteries. (Doctoral Dissertation). University of Wollongong. Retrieved from 0912 MATERIALS ENGINEERING ; https://ro.uow.edu.au/theses/3872

Chicago Manual of Style (16^th Edition):

Lu, Lin. “Transition-metal oxides, sulphide and sulphur composites for lithium batteries.” 2012. Doctoral Dissertation, University of Wollongong. Accessed January 24, 2021. 0912 MATERIALS ENGINEERING ; https://ro.uow.edu.au/theses/3872.

MLA Handbook (7^th Edition):

Lu, Lin. “Transition-metal oxides, sulphide and sulphur composites for lithium batteries.” 2012. Web. 24 Jan 2021.

Vancouver:

Lu L. Transition-metal oxides, sulphide and sulphur composites for lithium batteries. [Internet] [Doctoral dissertation]. University of Wollongong; 2012. [cited 2021 Jan 24]. Available from: 0912 MATERIALS ENGINEERING ; https://ro.uow.edu.au/theses/3872.

Council of Science Editors:

Lu L. Transition-metal oxides, sulphide and sulphur composites for lithium batteries. [Doctoral Dissertation]. University of Wollongong; 2012. Available from: 0912 MATERIALS ENGINEERING ; https://ro.uow.edu.au/theses/3872

Oregon State University

8. Grajczyk, Rosa. Structure-property relationships of YbFe₂O₄-type layered transition metal oxides.

Degree: PhD, Chemistry, 2014, Oregon State University

URL: http://hdl.handle.net/1957/48547

► The structure–property relationships of solid solutions within the YbFe₂O₄ family of compounds have been studied in relation to their optical, dielectric and magnetic properties. This… (more)

▼ The structure–property relationships of solid solutions within the YbFe₂O₄ family of compounds have been studied in relation to their optical, dielectric and magnetic properties. This family of compounds is of recent interest because of the trigonal bipyramid coordination that is rarely observed in transition metal oxides. The systematic study of InM³⁺M²⁺O₄ (M³⁺ = Al, Fe, Ga; M²⁺ = Cu, Mg) allowed for the trigonal bipyramidal site to be analyzed based on ionic radii, electron configurations and electronegativity differences. The solid solutions of InM³⁺Cu[subscript 1-x]MgxO₄ (M³⁺ = Al, Fe, Ga) exhibited a large increase in the c lattice parameter as a result of the difference in ionic behavior between Cu²⁺ and Mg²⁺. This structural observation was not present for InGa[subscript 1-x]Fe[subscript x]CuO₄, where the ionic radii and electronegativies of Ga³⁺ and Fe³⁺ are similar. The dielectric properties of InM³⁺Cu[subscript 1-x]Mg[subscript x]O₄ (M³⁺ = Al and Ga) were found to be the result of the Cu²⁺ d⁹ polarizability, but there were extremely large loss values because of remnant semiconductivity. All compositions were found to be frustrated antiferromagnets with spin glass behaviors at low temperatures, but when more than one magnetic cation was present, the magnetic properties showed indication of slight ferrimagnetism between the Fe³⁺ and Cu²⁺. The solid solutions of InGaMMꞌO₄ (M = Mg, Zn; Mꞌ = Co, Mg) displayed similar structural results to those found in the previous solid solutions, although the differences in electronegativies were not as influential. The optical properties of the cobalt containing compositions verified that the M²⁺ cations were located in a disordered trigonal bipyramidal site, with a dark purple color resulting from prominent d-d electronic transitions. The magnetic properties of the InGaMg[subscript 1-x]Co[subscript x]O₄ solid solution indicated that these compositions were spin glass systems with short-range antiferromagnetic interactions. To compare the trigonal bipyramidal layering schemes, the In₂Fe[subscript 2-x]Ga[subscript x]CuO₇ solid solution was compared to that of InFe[subscript 1-x]Ga[subscript x]CuO₄. The structural parameters of In₂Fe[subscript 2-x]Ga[subscript x]CuO₇ mirrored those of InFe[subscript 1-x]Ga[subscript x]CuO₄, but the magnetic properties were found to much more complex with the additional trigonal bipyramidal layer. It was determined that the single trigonal bipyramidal layer ferromagnetically interacted with the antiferromagnetic interactions within the double trigonal bipyramidal layer, particularly with x ≈ 1. Advisors/Committee Members: Subramanian, Munirpallam A. (advisor), Sleight, Arthur (committee member).

Subjects/Keywords: Chemistry; Transition metal oxides – Structure-activity relationships

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APA (6^th Edition):

Grajczyk, R. (2014). Structure-property relationships of YbFe₂O₄-type layered transition metal oxides. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/48547

Chicago Manual of Style (16^th Edition):

Grajczyk, Rosa. “Structure-property relationships of YbFe₂O₄-type layered transition metal oxides.” 2014. Doctoral Dissertation, Oregon State University. Accessed January 24, 2021. http://hdl.handle.net/1957/48547.

MLA Handbook (7^th Edition):

Grajczyk, Rosa. “Structure-property relationships of YbFe₂O₄-type layered transition metal oxides.” 2014. Web. 24 Jan 2021.

Vancouver:

Grajczyk R. Structure-property relationships of YbFe₂O₄-type layered transition metal oxides. [Internet] [Doctoral dissertation]. Oregon State University; 2014. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1957/48547.

Council of Science Editors:

Grajczyk R. Structure-property relationships of YbFe₂O₄-type layered transition metal oxides. [Doctoral Dissertation]. Oregon State University; 2014. Available from: http://hdl.handle.net/1957/48547

Michigan State University

9. Zhu, Mengze. Neutron scattering studies on correlated transition-metal oxides.

Degree: 2018, Michigan State University

URL: http://etd.lib.msu.edu/islandora/object/etd:6984

► "We have explored the collective phenomena of correlated electrons in two different transition-metal oxides, Ruddlesden-Popper type ruthenates (Sr,Ca)n+1RunO3n+1 and inverse-trirutile chromates Cr2MO6 (M = Te,… (more)

▼ "We have explored the collective phenomena of correlated electrons in two different transition-metal oxides, Ruddlesden-Popper type ruthenates (Sr,Ca)n+1RunO3n+1 and inverse-trirutile chromates Cr2MO6 (M = Te, Mo and W), using neutron scattering in combination with various material characterization methods. (Sr,Ca)n+1RunO3n+1 are 4d transition-metal oxides exhibiting competing magnetic and electronic tendencies. The delicate balance among the competing states can be readily tuned by perturbations, such as chemical doping and magnetic field, which gives rise to emergent phenomena. We have investigated the effects of 3d transition-metal doping on the magnetic and electronic properties of layered ruthenates. For instance, the single-layer (n = 1) Sr2RuO4 is an unconventional superconductor possessing an incommensurate spin density wave instability with a wave vector = (0.3 0.3 L) driven by Fermi surface nesting. Upon Fe substitution, we have unveiled an unexpected commensurate spin density wave order with a propagation vector = (0.25 0.25 0) in Sr2Ru1-xFexO4 (x = 0.03 and 0.05), despite the magnetic fluctuations persisting at . The latter feature is corroborated by the first principles calculations, which show that Fe doping barely changes the nesting vector of the Fermi surface. These results suggest that in addition to the known incommensurate magnetic instability, Sr2RuO4 is also in proximity to a commensurate magnetic tendency that can be stabilized via Fe doping. We have also studied the effects of a magnetic field. For example, the bilayer (n = 2) Ca3(Ru1-xTix)2O7 (x = 0.03) is a G-type antiferromagnetic Mott insulator. We have revealed that a modest magnetic field can lead to colossal magnetoresistance arising from an anomalous collapse of the Mott insulating state. Such an insulator-to-metal transition is accompanied by magnetic and structural transitions. These findings call for deeper theoretical studies to reexamine the magnetic field tuning of Mott systems with magnetic and electronic instabilities, as a magnetic field usually stabilizes the insulating ground state in Mott-Hubbard systems. Cr2MO6 (M = Te, W and Mo) are spin dimer systems with the magnetic ions Cr3+ structurally dimerized favoring a singlet ground state. However, all three compounds investigated exhibit long-range antiferromagnetic orders at low temperature owing to the inter-dimer interactions. We have shown that the inter-dimer exchange coupling can be tuned from antiferromagnetic in Cr2TeO6 to ferromagnetic in Cr2WO6 and Cr2MoO6, by altering the degree of d-p orbital hybridization between W(Mo) and O atoms. The tunability of the inter-dimer interactions without introducing additional complexities such as structural distortions and carrier doping offers a rare opportunity to drive the system toward the quantum critical point (QCP) separating the dimer-based quantum disordered state and the classical long-range antiferromagnetic order. Moreover, we have unraveled Higgs amplitude modes in the magnetic excitation spectra of Cr2TeO6 and… Advisors/Committee Members: Ke, Xianglin, Birge, Norman, Piermarocchi, Carlo, Pratt, Scott, Morelli, Donald.

Subjects/Keywords: Neutrons – Scattering; Transition metal oxides; Physics

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APA (6^th Edition):

Zhu, M. (2018). Neutron scattering studies on correlated transition-metal oxides. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:6984

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhu, Mengze. “Neutron scattering studies on correlated transition-metal oxides.” 2018. Thesis, Michigan State University. Accessed January 24, 2021. http://etd.lib.msu.edu/islandora/object/etd:6984.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhu, Mengze. “Neutron scattering studies on correlated transition-metal oxides.” 2018. Web. 24 Jan 2021.

Vancouver:

Zhu M. Neutron scattering studies on correlated transition-metal oxides. [Internet] [Thesis]. Michigan State University; 2018. [cited 2021 Jan 24]. Available from: http://etd.lib.msu.edu/islandora/object/etd:6984.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhu M. Neutron scattering studies on correlated transition-metal oxides. [Thesis]. Michigan State University; 2018. Available from: http://etd.lib.msu.edu/islandora/object/etd:6984

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

10. Liu, Vivian. Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3.

Degree: Materials Science & Engineering, 2015, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/55353 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37340/SOURCE02?view=true

► This thesis describes the growth and properties of epitaxially grown manganese oxide (Mn304) and iron oxide (Fe203)nanocrystals. A 2-step phase separation approach has been employed… (more)

▼ This thesis describes the growth and properties of epitaxially grown manganese oxide (Mn304) and iron oxide (Fe203)nanocrystals. A 2-step phase separation approach has been employed to achieve nanostructures with controlled surfaceorientation. AFM, SEM and TEM have all been carried out to determine the topography, as well as interfacial relationshipbetween substrate and sample. It provides a thorough investigation of the structural formation mechanism and how they correlateto the overall chemical and physical properties. ( 10 1) oriented M0304 is used as an example to demonstrate terrace formation onthe surface of individual island as a result of impurities. Terraces spirals in both right and left handed direction have beenobserved, with the upward climb distance approximately equal to half of the c-axis. The effect of increasing deposition frequencywas also investigated. Mn304 deposited at high frequency exhibited much larger and flatter structures. This can be explained byadatom arrangement, where at higher deposition frequency adatoms have less time to achieve 'vertical climb' hence resulting inflatter nano-islands.Having an understanding ofnanostructure formation also allows us to explore the electrochemical properties of(OOI) (101) and(I 12) orientations of Mn304. 1 0,000 cyclic voltammetry cycles have been run and repeated for each sample. Results suggest thatthe ( 112) orientation had the highest reactivity. Simulated atomic model of all three orientations confirms that theelectrochemical response increase corresponds to higher induced dipole moment. This is because increased number of dipolemoments can cause surface instability that is more prone to electrochemical reactions.The study into the interplay between surface morphology and property has been extended to iron oxide nanocrystals (a-F20 3).We found resistive switching behaviors when measured under conductive C-AFM, under applied voltage between -5V to +5V onnanocrystals between height range 25nm to 45nm. We observe hysteresis loop under reverse bias which exhibit rectifier diodebehaviour, which also increases with nanocrystal height. This phenomenon is attributed to the alternation of Fe between the 2+and 3+ valence states which is enhanced in larger (taller) nanocrystals. Advisors/Committee Members: Valanoor, Nagarajan, Materials Science & Engineering, Faculty of Science, UNSW.

Subjects/Keywords: Microscopy; Nanocrystal; Electrochemisty; Oxides; Transition Metal; Deposition

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APA (6^th Edition):

Liu, V. (2015). Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/55353 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37340/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Liu, Vivian. “Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3.” 2015. Doctoral Dissertation, University of New South Wales. Accessed January 24, 2021. http://handle.unsw.edu.au/1959.4/55353 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37340/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Liu, Vivian. “Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3.” 2015. Web. 24 Jan 2021.

Vancouver:

Liu V. Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3. [Internet] [Doctoral dissertation]. University of New South Wales; 2015. [cited 2021 Jan 24]. Available from: http://handle.unsw.edu.au/1959.4/55353 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37340/SOURCE02?view=true.

Council of Science Editors:

Liu V. Growth mechanism and electrochemical properties of Transition metal oxide nanostructures Mn3O4 and α-Fe2O3. [Doctoral Dissertation]. University of New South Wales; 2015. Available from: http://handle.unsw.edu.au/1959.4/55353 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:37340/SOURCE02?view=true

University of Texas – Austin

11. Li, Zongyao. Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering.

Degree: PhD, Materials Science & Engineering, 2018, University of Texas – Austin

URL: http://hdl.handle.net/2152/68072

► Transition metal oxides have attracted growing attention over the last few decades because of rich physical properties they exhibit. Perovskite structure transition metal oxides AMO₃… (more)

▼ Transition metal oxides have attracted growing attention over the last few decades because of rich physical properties they exhibit. Perovskite structure transition metal oxides AMO₃ are of particular interest to the design of functional materials in modern techniques, since a variety of ways can be used to tune the physical properties of AMO₃. Single crystals of Y₁₋ₓLaₓTiO₃ are grown by floating zone method to study the magnetic transition from ferromagnetic in YTiO₃ to G-type antiferromagnetic in LaTiO₃. Y₁₋ₓ LaₓTiO₃ shows similar magnetic phase diagram with RTiO₃ family, and the magnetism and the transition temperature can be finely tuned by varying the La doping x. By measuring the change of magnetic transition temperatures on single crystal samples under uniaxial stress, the correlation between the lattice distortions and the cooperative orbital ordering can be distinguished. Double perovskite CaMnTi₂O₆ is the first columnar A-site ordered perovskite exhibiting ferroelectric property. Spark plasma sintering (SPS) is used to successfully synthesize gram-level Ca₂₋ₓMnₓTi₂O₆, which has the same crystal structure and similar high-T [subscript c] ferroelectric property. Through neutron diffraction, the detailed information of the structure is obtained, and the driving force for ferroelectricity is identified. Inspired by the successful synthesis of double perovskite Ca₂₋ₓMnₓTi₂O₆, perovskites La₁₋ₓPrₓRuO₃ are obtained by SPS as well. The substitution of La by smaller rare earth ion Pr gives rise to the crossover from itinerant to localized electronic behavior. A systematical study of physical properties is made and an unusual second-order metal insulator transition is found in La₁₋ₓPrₓRuO₃. The A²⁺V₂O₄ spinels have the smallest gap caused by electron-electron correlations in the single-valent spinels, and the V-V bond length in these spinels decreases as the A-site cation is replaced by cations in the order of A = Cd, Mn, Fe, Mg, Zn, Co. The density functional theory (DFT) calculation and transport properties of CoV₂O₄ under pressure indicate that CoV₂O₄ might be at the crossover between localized electron and itinerant electronic behavior. In order to clarify this, the series of AV₂O₄ spinels (A = Cd, Mn, Fe, Mg, Zn, Co) are studied with in situ high-pressure x-ray and neutron diffraction at different temperatures. Advisors/Committee Members: Goodenough, John B. (advisor), Zhou, Jianshi (advisor).

Subjects/Keywords: Transition metal oxides; Perovskite; physical properties

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APA (6^th Edition):

Li, Z. (2018). Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/68072

Chicago Manual of Style (16^th Edition):

Li, Zongyao. “Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering.” 2018. Doctoral Dissertation, University of Texas – Austin. Accessed January 24, 2021. http://hdl.handle.net/2152/68072.

MLA Handbook (7^th Edition):

Li, Zongyao. “Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering.” 2018. Web. 24 Jan 2021.

Vancouver:

Li Z. Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2018. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/2152/68072.

Council of Science Editors:

Li Z. Physical properties of transition metal oxides synthesized by floating zone method and spark plasma sintering. [Doctoral Dissertation]. University of Texas – Austin; 2018. Available from: http://hdl.handle.net/2152/68072

University of Melbourne

12. Lim, Herianto. Optical switching and photoluminescence of erbium doped vanadium dioxide thin films.

Degree: 2012, University of Melbourne

URL: http://hdl.handle.net/11343/37739

► Information technology is now demanding groundbreaking innovations to increase communication and computation bandwidth. The electronic communication systems we use today are already reaching the limits.… (more)

▼ Information technology is now demanding groundbreaking innovations to increase communication and computation bandwidth. The electronic communication systems we use today are already reaching the limits. Data transmission through electrical wires is not energy efficient due to power dissipation as heat, while data processing of a CPU chip is capped in speed by the transmission rate of the electrons. Recent developments in optical fibers have solved part of the problem, which enable transmission of data at the speed of light and at low power. The installations of fiber-optic communication systems are taking place world-wide at an astonishing rate. Research was recently focused on developing optical substitutes for other electronic technologies. An optical switch is one of these substitutes. Vanadium dioxide (VO2) is a promising material for an optical switch. The transition metal oxides undergo the insulator – metal transition (IMT) that involve drastic changes in electrical and optical properties. The most desirable features of VO2 are that the switching is ultrafast when induced optically and the energy threshold of the transition is relatively low. This thesis investigates the possibilities of enhancing a VO2-based optical switch with the capability of signal amplification via the incorporation of erbium (Er). Er has been used extensively in fiber-optic technology as a signal amplifier, due to its luminescence at 1535 nm which lies in the wavelength window of the minimal transfer loss in optical fibers. Our experimental methods involve temperature-driven optical switching tests and photoluminescence spectroscopy on Er implanted VO2 thin films. The observations of the IMT of VO2 and the photoluminescence of Er in the thin films will be vital in determining whether VO2:Er would work as an optical switch and amplifier as expected. A range of implantation and post-annealing schemes are also explored in an attempt to find the optimal processing conditions that would maximize the qualities of the optical switching and photoluminescence. To facilitate our research, the first preliminary theoretical analysis of the VO2:Er system is presented. We also introduce a theoretical framework on calculating the transition probability of the IMT in VO2 from experimental data. In addition, we show how a metastable phase is related to a peculiar observation in the changes of the optical properties during the IMT.

Subjects/Keywords: vanadium dioxide; erbium; insulator-metal transition; photoluminescence; transition metal oxides

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APA (6^th Edition):

Lim, H. (2012). Optical switching and photoluminescence of erbium doped vanadium dioxide thin films. (Masters Thesis). University of Melbourne. Retrieved from http://hdl.handle.net/11343/37739

Chicago Manual of Style (16^th Edition):

Lim, Herianto. “Optical switching and photoluminescence of erbium doped vanadium dioxide thin films.” 2012. Masters Thesis, University of Melbourne. Accessed January 24, 2021. http://hdl.handle.net/11343/37739.

MLA Handbook (7^th Edition):

Lim, Herianto. “Optical switching and photoluminescence of erbium doped vanadium dioxide thin films.” 2012. Web. 24 Jan 2021.

Vancouver:

Lim H. Optical switching and photoluminescence of erbium doped vanadium dioxide thin films. [Internet] [Masters thesis]. University of Melbourne; 2012. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/11343/37739.

Council of Science Editors:

Lim H. Optical switching and photoluminescence of erbium doped vanadium dioxide thin films. [Masters Thesis]. University of Melbourne; 2012. Available from: http://hdl.handle.net/11343/37739

Penn State University

13. Zhang, Haitian. GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS.

Degree: 2018, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/14959huz115

► Transition metal oxides have attracted tremendous research interest due to their fertile functional properties, including ferroelectricity, magnetism, high temperature superconductivity and metal to insulator transition… (more)

▼ Transition metal oxides have attracted tremendous research interest due to their fertile functional properties, including ferroelectricity, magnetism, high temperature superconductivity and metal to insulator transition (MIT). Over recent decades, one of the research focuses has been utilizing these functional features in device applications, which requires a deeper understanding of the material science and also advances in thin film deposition in order to tailor these properties. The binary vanadium dioxide has drawn much attention due to its orders of magnitude change in resistivity during the MIT near room temperature, opening up the possibilities to use this material as next generation transistors, memory devices and radio frequency switches in communication applications. However, to bridge the gap between the frontier of fundamental research in VO2 films and their realization in commercial products, wafer scale growth of the oxide thin films with ‘electronic grade’ is necessary. This task requires precise control over the valence state of normally multivalent transition metal cations, while the device performance will be largely derogated if the valence state is not well controlled. To deposit the VO2 with precise valence state control on wafer scale, a combinatorial approach was used to establish a valence state gradient of vanadium cation, from which the optimal condition for stoichiometric VO2 was extracted. Under the optimal growth condition, a high quality 30-nm thick VO2 film was grown on 3 inch sapphire wafer, showing the highest MIT resistivity ratio for ultrathin films on wafer scale, which is relevant for modern device applications. Besides the growth of high quality MIT thin films on wafer scale, a novel strategy to optically write and erase complex circuitry into VO2 thin films was also developed. We’ve successfully demonstrated the optically induced MIT in VO2 which is persistent after the light source is turned off. We use this method to optically imprint local conductive areas into an otherwise insulating VO2 film. In contrast to conventional thin film patterning techniques that require chemical etching of patterns defined through lithography steps, the optical imprint is performed by irradiating single crystalline VO2 thin films with focused ultraviolet light in a nitrogen atmosphere. A conductive pattern is sketched into the resistive VO2 matrix, resulting in a close to 4 orders of magnitude increase in electrical conductivity at room temperature. Significantly, the inscribed pattern, which is permanent, can be completely erased by a few minutes thermal annealing process at moderately elevated temperature. This development can potentially find its application in reconfigurable optical elements. It can also be harnessed as rewritable bottom electrode material for back-gating structures by inscribing complex contacting schemes using UV radiation. Beyond the binary vanadium oxides, Mott insulators such as LaVO3 have recently been suggested as promising solar cell materials with suitable band… Advisors/Committee Members: Roman Engel-Herbert, Dissertation Advisor/Co-Advisor, Roman Engel-Herbert, Committee Chair/Co-Chair, Venkatraman Gopalan, Committee Member, Long-Qing Chen, Committee Member, Chris Giebink, Outside Member.

Subjects/Keywords: Molecular beam epitaxy; Thin film; Strongly correlated oxides; Transition metal oxides; Metal to insulator transition; VO2; LaVO3

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APA (6^th Edition):

Zhang, H. (2018). GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/14959huz115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Haitian. “GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS.” 2018. Thesis, Penn State University. Accessed January 24, 2021. https://submit-etda.libraries.psu.edu/catalog/14959huz115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Haitian. “GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS.” 2018. Web. 24 Jan 2021.

Vancouver:

Zhang H. GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS. [Internet] [Thesis]. Penn State University; 2018. [cited 2021 Jan 24]. Available from: https://submit-etda.libraries.psu.edu/catalog/14959huz115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang H. GROWTH AND FUNCTIONALITIES OF VANADATE THIN FILMS. [Thesis]. Penn State University; 2018. Available from: https://submit-etda.libraries.psu.edu/catalog/14959huz115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Drexel University

14. Pai, Rahul Nagesh Neeta. Iron-oxide based electrodes in aqueous supercapacitors.

Degree: 2017, Drexel University

URL: http://hdl.handle.net/1860/idea:7810

►

Climate change and the limited availability of fossil fuels have greatly affected the world economy and ecology. The demand of energy is not coping up… (more)

▼

Climate change and the limited availability of fossil fuels have greatly affected the world economy and ecology. The demand of energy is not coping up the supply of the same. With a fast-growing market for portable electronic devices and the development of hybrid electric vehicles, there has been an ever increasing and urgent demand for environmentally friendly high-power energy resources. This has led to development of energy storage devices, mostly supercapacitors and batteries. In the recent times it is seen that li-ion batteries have been dominating energy storage device sector (Portable electronics, hybrid vehicles and grids). Li-ion still lacks when there is sudden demand in high power. The development of higher energy and power density systems highly rely upon the advancement of new materials used in these devices. Transition oxides and conducting polymers based nanofibers are excellent candidates for application as electrodes in the energy storage devices because of their unique properties such as high capacitance, chemical durability, nature friendly and high specific surface area. Electrospinning is a simple, fast and a scalable technique wherein fiber formation is done with the help of a strong electric field to stretch out a polymer solution to form nanofibers with diameters in the range of 100-800 nm. This fiber-formation technique results in formation of free-standing, binder free and non-woven fiber mat. My thesis focuses on preparation of Iron oxide based nanofibers through electrospinning method, characterizing these nanofibers via spectroscopic/microscopic techniques and developing understanding of their electrochemical mechanisms in an aqueous medium. My work focusses more on structurally supporting these oxides in the conductive carbon fiber matrix which otherwise delaminates while cycling reducing performance in energy storage devices.

M.S., Chemical Engineering – Drexel University, 2017

Advisors/Committee Members: Kalra, Vibha, College of Engineering.

Subjects/Keywords: Chemical engineering; Power resources; Carbon nanofibers; Electrospinning; Iron oxides; Supercapacitor; Transition metal oxides

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APA (6^th Edition):

Pai, R. N. N. (2017). Iron-oxide based electrodes in aqueous supercapacitors. (Thesis). Drexel University. Retrieved from http://hdl.handle.net/1860/idea:7810

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pai, Rahul Nagesh Neeta. “Iron-oxide based electrodes in aqueous supercapacitors.” 2017. Thesis, Drexel University. Accessed January 24, 2021. http://hdl.handle.net/1860/idea:7810.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pai, Rahul Nagesh Neeta. “Iron-oxide based electrodes in aqueous supercapacitors.” 2017. Web. 24 Jan 2021.

Vancouver:

Pai RNN. Iron-oxide based electrodes in aqueous supercapacitors. [Internet] [Thesis]. Drexel University; 2017. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1860/idea:7810.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pai RNN. Iron-oxide based electrodes in aqueous supercapacitors. [Thesis]. Drexel University; 2017. Available from: http://hdl.handle.net/1860/idea:7810

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Oregon State University

15. Jiang, Peng. Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures.

Degree: PhD, Chemistry, 2012, Oregon State University

URL: http://hdl.handle.net/1957/33641

► Transition metal oxides exhibit potential in various application fields due to the special d-electrons. Solid state chemistry focuses on discovering the structure-property relationships. The work… (more)

▼ Transition metal oxides exhibit potential in various application fields due to the special d-electrons. Solid state chemistry focuses on discovering the structure-property relationships. The work in this thesis mainly discusses compounds with hexagonal or brownmillerite-type structure and their practical properties. Hexagonal YIn[subscript 1-x]Fe[subscript x]O₃ (x = 0-0.3, 0.7-1.0) phases have been prepared and characterized. All phases appear to have the ferroelectric structure known for YInO₃. The color of the phases changes from yellow to orange to dark red with increasing Fe content. Magnetic measurements confirm high-spin Fe³⁺ for all phases. Similarly, solid solution YAl[subscript 1-x]Fe[subscript x]O₃ (x = 0-0.4, 0.7-1.0) phases were successfully synthesized through the sol-gel method. The Al-rich compounds present paraelectric YAlO₃ structure while the Fe-rich side samples exhibit YFeO₃ structure. The color of the compounds appear to be yellow with small Fe content and change to brown which has higher Fe content. Brownmillerite-type oxides Ba₂In[subscript 2-x]Mn[subscript x]O[subscript 5+x] (x = 0.1-0.7) have been prepared and characterized. Magnetic measurements confirm that Mn in as prepared samples is substituting as Mn⁵⁺ for all values of x with observed paramagnetic spin-only moments close to values expected for two unpaired electrons. Neutron diffraction structure refinements show Mn⁵⁺ occupies tetrahedral sites for orthorhombic (x = 0.1) and tetragonal (x = 0.2) phases. For Mn ≥ 0.3 samples, neutron refinements show the phases are cubic with disordered cations and oxygen vacancies. The colors of the phases change from light yellow (x = 0) to intense turquoise (x =0.1), to green (x = 0.2, 0.3) or dark green (x ≥ 0.4). Solid solution Ba₂In[subscript 2-x]Fe[subscript x]O[subscript 5+y] (x = 0.1-1.5) also exhibit brownmillerite-type structure. The color of the compounds appear to be green with small Fe content and change to black with higher Fe content (x ≥ 0.3). Magnetic measurements and Mössbauer spectroscopy conclude the mixed valence of Fe³⁺/Fe⁴⁺ for all the phases. Nonstoichiometry compound YCu₀.₆Ti₀.₄O[subscript 3-δ] has been prepared and characterized. Structure study indicates that oxygen vacancy is favored under the synthesis condition. This change in oxygen content was further studied in the Mn-doped system. And the effect of stoichiometric difference in the Mn-doped samples was not as obvious as the initial compound. The disorder in the cation site enhanced the tolerance of the structure in the aspect of oxygen content. The hexagonal phases LnCu₀.₅Ti₀.₅O₃ (Ln = Y, Tb-Lu) phases were prepared by the traditional solid state reactions. The prepared compounds were reduced at high temperature in the reduction atmosphere created by the H₂/N₂ gas mixture. Study on the structure and properties changes by reduction was conducted by X-ray diffraction, optical measurement, magnetic measurement and thermalgravimetric analysis. And we observed some evidence of the presence of Cu⁺ in the reduced phase by… Advisors/Committee Members: Subramanian, Munirpallam (advisor), Kong, Wei (committee member).

Subjects/Keywords: oxides with hexagonal AMO3 related structures; Transition metal oxides – Structure-activity relationships

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APA (6^th Edition):

Jiang, P. (2012). Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/33641

Chicago Manual of Style (16^th Edition):

Jiang, Peng. “Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures.” 2012. Doctoral Dissertation, Oregon State University. Accessed January 24, 2021. http://hdl.handle.net/1957/33641.

MLA Handbook (7^th Edition):

Jiang, Peng. “Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures.” 2012. Web. 24 Jan 2021.

Vancouver:

Jiang P. Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures. [Internet] [Doctoral dissertation]. Oregon State University; 2012. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1957/33641.

Council of Science Editors:

Jiang P. Structure-property relationships of oxides with hexagonal AMO₃ and brownmillerite related structures. [Doctoral Dissertation]. Oregon State University; 2012. Available from: http://hdl.handle.net/1957/33641

Tulane University

16. Luo, Sijun. Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films.

Degree: 2017, Tulane University

URL: https://digitallibrary.tulane.edu/islandora/object/tulane:77017

1

Sijun Luo

Advisors/Committee Members: Chrisey, Douglas (Thesis advisor), School of Science & Engineering Physics and Engineering Physics (Degree granting institution).

Subjects/Keywords: transition metal oxides thin films

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APA (6^th Edition):

Luo, S. (2017). Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films. (Thesis). Tulane University. Retrieved from https://digitallibrary.tulane.edu/islandora/object/tulane:77017

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Luo, Sijun. “Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films.” 2017. Thesis, Tulane University. Accessed January 24, 2021. https://digitallibrary.tulane.edu/islandora/object/tulane:77017.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Luo, Sijun. “Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films.” 2017. Web. 24 Jan 2021.

Vancouver:

Luo S. Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films. [Internet] [Thesis]. Tulane University; 2017. [cited 2021 Jan 24]. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:77017.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Luo S. Pulsed photoinitiated fabrication of transition metal oxides-reduced graphitic oxides nanocomposite thin films. [Thesis]. Tulane University; 2017. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:77017

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

17. Birol, Turan. An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides.

Degree: PhD, Physics, 2013, Cornell University

URL: http://hdl.handle.net/1813/34362

► Transition metal oxides form a large class of compounds that exhibit a very rich and diverse physics. This thesis involves a first-principles computational study of… (more)

Subjects/Keywords: transition metal oxides; density functional theory; ferroelectricity; magnetoelectric effect

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APA (6^th Edition):

Birol, T. (2013). An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/34362

Chicago Manual of Style (16^th Edition):

Birol, Turan. “An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides.” 2013. Doctoral Dissertation, Cornell University. Accessed January 24, 2021. http://hdl.handle.net/1813/34362.

MLA Handbook (7^th Edition):

Birol, Turan. “An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides.” 2013. Web. 24 Jan 2021.

Vancouver:

Birol T. An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides. [Internet] [Doctoral dissertation]. Cornell University; 2013. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1813/34362.

Council of Science Editors:

Birol T. An Ab Initio Study Of The Structural, Magnetic, And Electronic Properties Of Transition Metal Oxides. [Doctoral Dissertation]. Cornell University; 2013. Available from: http://hdl.handle.net/1813/34362

Penn State University

18. Zhang, Lei. Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/18985

► This thesis describes the thermodynamic modeling of the La2O3-TiO2 system, SrCoO3-δ perovskite with extension to Sr-doped LaCoO3-δ. By using CALPHAD (CALculation of PHAse Diagram) method,… (more)

Subjects/Keywords: CALPHAD; transition metal oxides; phase stability; first-principles; defect

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APA (6^th Edition):

Zhang, L. (2013). Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/18985

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Lei. “Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods.” 2013. Thesis, Penn State University. Accessed January 24, 2021. https://submit-etda.libraries.psu.edu/catalog/18985.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Lei. “Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods.” 2013. Web. 24 Jan 2021.

Vancouver:

Zhang L. Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Jan 24]. Available from: https://submit-etda.libraries.psu.edu/catalog/18985.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang L. Thermodynamic investigation of transition metal oxides via CALPHAD and first-principles methods. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/18985

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Oregon State University

19. Li, Jun. Synthesis, structure and properties of some transition metal oxides.

Degree: PhD, Chemistry, 2005, Oregon State University

URL: http://hdl.handle.net/1957/19040

See pdf Advisors/Committee Members: Sleight, Arthur W. (advisor), Keszler, Douglas (committee member).

Subjects/Keywords: Transition metal oxides – Synthesis

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APA (6^th Edition):

Li, J. (2005). Synthesis, structure and properties of some transition metal oxides. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/19040

Chicago Manual of Style (16^th Edition):

Li, Jun. “Synthesis, structure and properties of some transition metal oxides.” 2005. Doctoral Dissertation, Oregon State University. Accessed January 24, 2021. http://hdl.handle.net/1957/19040.

MLA Handbook (7^th Edition):

Li, Jun. “Synthesis, structure and properties of some transition metal oxides.” 2005. Web. 24 Jan 2021.

Vancouver:

Li J. Synthesis, structure and properties of some transition metal oxides. [Internet] [Doctoral dissertation]. Oregon State University; 2005. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1957/19040.

Council of Science Editors:

Li J. Synthesis, structure and properties of some transition metal oxides. [Doctoral Dissertation]. Oregon State University; 2005. Available from: http://hdl.handle.net/1957/19040

Boston University

20. Wang, Yu. Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications.

Degree: PhD, Electrical & Computer Engineering, 2016, Boston University

URL: http://hdl.handle.net/2144/19507

► Alternative plasmonic materials of Transparent Nitrides and Conductive Oxides (TNCOs) including Indium Tin Oxide (ITO), Al-doped ZnO (AZO) and Titanium Nitride (TiN), have been proposed… (more)

▼ Alternative plasmonic materials of Transparent Nitrides and Conductive Oxides (TNCOs) including Indium Tin Oxide (ITO), Al-doped ZnO (AZO) and Titanium Nitride (TiN), have been proposed as novel material platforms for Si-compatible plasmonics and metamaterials, showing enhanced light-matter interaction over a broad spectral range. It has been recently shown that these materials feature reduced optical losses compared with conventional noble metals such as Au and Ag in the visible and near-infrared spectral range. However, it is still an open challenge to tailor the structural and optical properties of these materials, and to further reduce their optical losses, in order to effectively utilize them in photonic devices. In this thesis work, I demonstrate wide tunability of the optical and structural properties of ITO, AZO and TiN thin films, by using post-deposition annealing treatments, enabling significant reduction of their optical losses. By measuring the optical bandgaps of the investigated materials, I show that the tunability of the optical properties originates from the modulation of the free carrier concentration induced by the annealing treatment. Moreover, I perform XRD characterization of the fabricated films, indicating that the annealing also effectively tunes the grain size, which is consistent with the change of the optical properties. Eventually, I investigate the role of the annealing gases for ITO and AZO, demonstrating that free-carrier modulation in ITO and AZO is due to the change in the density of oxygen vacancies after post-deposition annealing. In particular, TNCOs possess epsilon-near-zero (ENZ) condition in near-infrared range with optical loss ε^"<1, thus providing enhanced internal fields in the medium at the ENZ condition. In collaboration with Prof. Nader Engheta and the previous post-doc in our group Dr. Antonio Capretti, we demonstrate enhanced second-harmonic generation (SHG) and third-harmonic generation (THG) from ITO thin films driven by ENZ condition. It results that the SHG generation efficiency is comparable with that of a crystalline quartz plate of thickness 0.5 mm, and that the THG generation efficiency is ∼600 times larger than crystalline silicon. As an application for the fabricated TiN material, I investigate PL intensity and lifetime in Hyperbolic Metamaterials (HMMs) coupled with emitting Si Quantum Dots (QDs). In collaboration with Hiroshi Sugimoto in Prof. Minoru Fujii’s group and the previous post-doc in our group Dr. Sandeep Inampudi, we demonstrate up to 1.6-times enhanced decay rate of QDs emission. Photonic devices based on TNCO plasmonic materials offer an effective approach for the engineering of novel Si-based photonic devices with enhanced light-matter coupling over a broad spectral range. As an application for the fabricated ITO, in collaboration with Hongwei Zhao in Prof. Jonathan Klamkin’s group, electro-absorption modulators are numerically investigated to show high extinction ration of greater than 6dB, while insertion loss is less than…

Subjects/Keywords: Electrical engineering; Metamaterials; Plasmonics; Transition metal nitrides; Transparent conductive oxides

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APA (6^th Edition):

Wang, Y. (2016). Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/19507

Chicago Manual of Style (16^th Edition):

Wang, Yu. “Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications.” 2016. Doctoral Dissertation, Boston University. Accessed January 24, 2021. http://hdl.handle.net/2144/19507.

MLA Handbook (7^th Edition):

Wang, Yu. “Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications.” 2016. Web. 24 Jan 2021.

Vancouver:

Wang Y. Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications. [Internet] [Doctoral dissertation]. Boston University; 2016. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/2144/19507.

Council of Science Editors:

Wang Y. Engineering Si-compatible materials based on transparent nitrides and conductive oxides (TNCOs) for broadband active plasmonic and metamaterials applications. [Doctoral Dissertation]. Boston University; 2016. Available from: http://hdl.handle.net/2144/19507

University of Edinburgh

21. Hunter, Emily Claire. An exploration of novel correlated electronic states in 5d transition metal oxides.

Degree: PhD, 2016, University of Edinburgh

URL: http://hdl.handle.net/1842/22008

► The crystal growth conditions of compounds of the series Srn+1IrnO3n+1 (n=1, 2 and ∞) are investigated. It was found that the ratio of IrO2:SrCO3 in… (more)

Subjects/Keywords: 548; 5d transition metal oxides; correlated electron systems

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APA (6^th Edition):

Hunter, E. C. (2016). An exploration of novel correlated electronic states in 5d transition metal oxides. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/22008

Chicago Manual of Style (16^th Edition):

Hunter, Emily Claire. “An exploration of novel correlated electronic states in 5d transition metal oxides.” 2016. Doctoral Dissertation, University of Edinburgh. Accessed January 24, 2021. http://hdl.handle.net/1842/22008.

MLA Handbook (7^th Edition):

Hunter, Emily Claire. “An exploration of novel correlated electronic states in 5d transition metal oxides.” 2016. Web. 24 Jan 2021.

Vancouver:

Hunter EC. An exploration of novel correlated electronic states in 5d transition metal oxides. [Internet] [Doctoral dissertation]. University of Edinburgh; 2016. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1842/22008.

Council of Science Editors:

Hunter EC. An exploration of novel correlated electronic states in 5d transition metal oxides. [Doctoral Dissertation]. University of Edinburgh; 2016. Available from: http://hdl.handle.net/1842/22008

Hong Kong University of Science and Technology

22. Wei, Zhaohuan. Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries.

Degree: 2016, Hong Kong University of Science and Technology

URL: http://repository.ust.hk/ir/Record/1783.1-80387 ; https://doi.org/10.14711/thesis-b1585069 ; http://repository.ust.hk/ir/bitstream/1783.1-80387/1/th_redirect.html

► The non-aqueous lithium-oxygen battery has been attracting increasing attention over the past years primarily due to its high capacity and energy density. However, to make… (more)

Subjects/Keywords: Lithium ion batteries ; Materials ; Oxygen compounds ; Transition metal oxides ; Electrodes ; Cathodes

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APA (6^th Edition):

Wei, Z. (2016). Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries. (Thesis). Hong Kong University of Science and Technology. Retrieved from http://repository.ust.hk/ir/Record/1783.1-80387 ; https://doi.org/10.14711/thesis-b1585069 ; http://repository.ust.hk/ir/bitstream/1783.1-80387/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wei, Zhaohuan. “Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries.” 2016. Thesis, Hong Kong University of Science and Technology. Accessed January 24, 2021. http://repository.ust.hk/ir/Record/1783.1-80387 ; https://doi.org/10.14711/thesis-b1585069 ; http://repository.ust.hk/ir/bitstream/1783.1-80387/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wei, Zhaohuan. “Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries.” 2016. Web. 24 Jan 2021.

Vancouver:

Wei Z. Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries. [Internet] [Thesis]. Hong Kong University of Science and Technology; 2016. [cited 2021 Jan 24]. Available from: http://repository.ust.hk/ir/Record/1783.1-80387 ; https://doi.org/10.14711/thesis-b1585069 ; http://repository.ust.hk/ir/bitstream/1783.1-80387/1/th_redirect.html.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wei Z. Preparations and characterizations of cathode electrodes for non-aqueous lithium-oxygen batteries. [Thesis]. Hong Kong University of Science and Technology; 2016. Available from: http://repository.ust.hk/ir/Record/1783.1-80387 ; https://doi.org/10.14711/thesis-b1585069 ; http://repository.ust.hk/ir/bitstream/1783.1-80387/1/th_redirect.html

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Clemson University

23. Kolambage, Mudithangani. Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides.

Degree: PhD, Chemistry, 2020, Clemson University

URL: https://tigerprints.clemson.edu/all_dissertations/2613

► The second row third row transition metal ions and their compounds are quite interesting due to their strong spin-orbit coupling interactions, which make them… (more)

▼ The second row third row transition metal ions and their compounds are quite interesting due to their strong spin-orbit coupling interactions, which make them very different from their 3-d counterparts. This places these 4-d and 5-d transition metal ions between 3-d transition metals where the splitting is dominated by orbital effects and rare earth ions where the splitting is dominated by spin-orbit interactions. This can lead to some unusual and novel physical properties which may eventually lead to novel device possibilities. However, the chemistry of these heavy d block oxides are largely ignored compared to 3-d transition metal chemistry. In this work we have focused on the synthesis of oxides containing these heavy transition metal ions and lanthanides. The highly refractory nature of these heavy d block oxides pose limitations on the use of conventional high temperature synthetic routes. These high temperature synthetic routes typically result in many site defects, disorder, non-stoichiometry in crystal lattices and also impurities from high temperature crucibles, which has a great impact on the physical properties of these materials. Therefore, a low temperature synthetic route such as the hydrothermal technique is useful for these extremely refractory compounds. The exploration of mixed metal oxide systems containing Re, Ru, Ta and W has led to the identification of high quality single crystals of many novel and existing compounds. For example, single crystals of highly dense LnTaO4 compounds were obtained which would be potential laser host materials for high energy radiation. Several new structure types of Re, Ru, Ta and W systems were identified and this also revealed new structural possibilities for these transition metal ions. Solubility of the ReO2, RuO2, Ta2O5 and WO2 building blocks were achieved well below their melting point (600-750 ⁰C) and this minimized the common problems observed in conventional high temperature synthetic methods such as non-stoichiometry, lattice defects, disorder, and good quality single crystals were obtained with a good purity in most cases. Advisors/Committee Members: Joseph W Kolis, Shiou-Jyh Hwu, Jeffrey Anker, Bill Pennington.

Subjects/Keywords: Hydrothermal; Lanthanide; Refractory oxides; Rhenium; Single crystal; Transition Metal

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APA (6^th Edition):

Kolambage, M. (2020). Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides. (Doctoral Dissertation). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_dissertations/2613

Chicago Manual of Style (16^th Edition):

Kolambage, Mudithangani. “Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides.” 2020. Doctoral Dissertation, Clemson University. Accessed January 24, 2021. https://tigerprints.clemson.edu/all_dissertations/2613.

MLA Handbook (7^th Edition):

Kolambage, Mudithangani. “Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides.” 2020. Web. 24 Jan 2021.

Vancouver:

Kolambage M. Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides. [Internet] [Doctoral dissertation]. Clemson University; 2020. [cited 2021 Jan 24]. Available from: https://tigerprints.clemson.edu/all_dissertations/2613.

Council of Science Editors:

Kolambage M. Hydrothermal Crystal Growth and Characterization of Refractory Oxides Containing 4d, 5d Transition Metal Ions and Lanthanides. [Doctoral Dissertation]. Clemson University; 2020. Available from: https://tigerprints.clemson.edu/all_dissertations/2613

Seton Hall University

24. Kurywczak, Eric. d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES).

Degree: MS Physics, Physics, 2020, Seton Hall University

URL: https://scholarship.shu.edu/dissertations/2765

► XANES L₂ and L₃-edge X-Ray Absorption Near Edge Spectra (XANES) for 4d and 5d row transition metals (TM) oxides are assumed to be directly… (more)

Subjects/Keywords: XANES; Electronic Structure; Transition Metal Oxides; Condensed Matter Physics

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APA (6^th Edition):

Kurywczak, E. (2020). d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES). (Doctoral Dissertation). Seton Hall University. Retrieved from https://scholarship.shu.edu/dissertations/2765

Chicago Manual of Style (16^th Edition):

Kurywczak, Eric. “d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES).” 2020. Doctoral Dissertation, Seton Hall University. Accessed January 24, 2021. https://scholarship.shu.edu/dissertations/2765.

MLA Handbook (7^th Edition):

Kurywczak, Eric. “d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES).” 2020. Web. 24 Jan 2021.

Vancouver:

Kurywczak E. d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES). [Internet] [Doctoral dissertation]. Seton Hall University; 2020. [cited 2021 Jan 24]. Available from: https://scholarship.shu.edu/dissertations/2765.

Council of Science Editors:

Kurywczak E. d-Orbital Occupancy of Transition Metal Oxides by X-Ray Absorption Near Edge Structure (XANES). [Doctoral Dissertation]. Seton Hall University; 2020. Available from: https://scholarship.shu.edu/dissertations/2765

25. Alidoust, Nima. First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion .

Degree: PhD, 2015, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp011r66j351z

► Global climate change and pollution caused by fossil fuels necessitate the search for inexpensive, clean, renewable energy sources. Photocatalytic and photovoltaic solar energy conversion to… (more)

▼ Global climate change and pollution caused by fossil fuels necessitate the search for inexpensive, clean, renewable energy sources. Photocatalytic and photovoltaic solar energy conversion to fuels and electricity, respectively, are among the possible solutions to this challenge. Engineering devices that can efficiently achieve these tasks requires fundamental understanding of the materials involved, identification of ways to improve these materials, and discovery of new materials that could help achieve higher efficiencies and lower costs. The work presented in this dissertation contributes to these fronts via first-principles quantum mechanical calculations. In particular, we extensively study nickel oxide (NiO), an inexpensive semiconductor, with the desired potentially carrier-lifetime-extending charge-transfer property. We identify and devise various theoretical models that accurately describe NiO¿s electronic structure. We use these models to show that alloying NiO with Li2O could decrease NiO¿s band gap from ~4 eV to ~2 eV, making it an appropriate light absorber for use in various solar energy conversion devices. We study hole transport in NiO and NiO alloys. We show that hole conductivity in NiO can be enhanced by forming homogeneous LixNi1-xO alloys with high enough Li concentration, making LixNi1-xO alloys suitable for use as p-type hole conductors. We further find that hole transport in NiO is confined to two dimensions. We predict that forming MgxNi1-xO and ZnxNi1-xO (which we find to be transparent to visible light) disrupts this confinement and leads to three-dimensional hole transport, thereby increasing conductivity. This makes MgxNi1-xO and ZnxNi1-xO alloys suitable for use as transparent conducting oxides. We introduce CoO and Co0.25Ni0.75O alloy as new intermediate band semiconductors (IBSCs), capable of absorbing light across multiple band gaps and enhancing light absorption in IBSC-based solar cells. Finally, we investigate the spatial concentration of hole and electron states in methylammonium (MA) lead iodide (MAPbI3), a promising material for photovoltaic devices. We show that although some orientations of the MA ion in the crystal structure may lead to spatial separation between hole and electron states, this spatial separation does produce lower overlap between these states and therefore we conclude it is not responsible for the long carrier lifetimes in MAPbI3. Advisors/Committee Members: Carter, Emily Ann (advisor).

Subjects/Keywords: Nickel oxide; Photocatalysis; Photovoltaics; Quantum mechanics; Solar energy; Transition-metal oxides

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APA (6^th Edition):

Alidoust, N. (2015). First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp011r66j351z

Chicago Manual of Style (16^th Edition):

Alidoust, Nima. “First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion .” 2015. Doctoral Dissertation, Princeton University. Accessed January 24, 2021. http://arks.princeton.edu/ark:/88435/dsp011r66j351z.

MLA Handbook (7^th Edition):

Alidoust, Nima. “First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion .” 2015. Web. 24 Jan 2021.

Vancouver:

Alidoust N. First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion . [Internet] [Doctoral dissertation]. Princeton University; 2015. [cited 2021 Jan 24]. Available from: http://arks.princeton.edu/ark:/88435/dsp011r66j351z.

Council of Science Editors:

Alidoust N. First Principles Evaluation of Nickel Oxide and Other Materials for Solar Energy Conversion . [Doctoral Dissertation]. Princeton University; 2015. Available from: http://arks.princeton.edu/ark:/88435/dsp011r66j351z

26. ROMERAL FERNANDEZ, LUIS ANDRES. Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution.

Degree: School of Chemistry. Discipline of Chemistry, 2019, Trinity College Dublin

URL: http://hdl.handle.net/2262/89088

► There has been an abundance of publications over the last twenty years on electrode materials proposed to be suitable catalysts for the oxygen evolution reaction… (more)

▼ There has been an abundance of publications over the last twenty years on electrode materials proposed to be suitable catalysts for the oxygen evolution reaction (OER) in alkaline solutions. Although it is widely accepted that RuO2 and IrO2 anodes exhibit the most efficient electrocatalyst performance towards the reaction, their high cost renders prohibitive the widespread adoption of this material for industrial applications. Amongst the more costeffective materials that have been proposed as OER anodes are, various inter-metallic alloys, typically containing Ni, Co or Fe, and transition mixed oxides, including spinels (particularly nickelites, cobalites and ferrites) and perovskites. In view of this, the present work investigates the redox, the electrocatalytic and the mechanistic properties of two types of electrodes based on transition metal oxides were examined for the oxygen evolution reaction. The oxide materials were repetitive potential multi-cycled prepared hydrous manganese oxide electrodes and thermally prepared nickel cobalt mixed oxide electrodes. The electrocatalytic properties of both were described for potential use in the industrially and commercially significant OER, which is a rate determining step for hydrogen production via alkaline water electrolysis. Thus, the ?backbone? of the present work is to be found in the steady-state polarisation and electrochemical impedance measurements. The aim of these measurements was to obtain experimental values for the OER Tafel slope and the OH- ion reaction order for these electrodes in aqueous alkaline solution, with a view to perform classical kinetic mechanistic analyses, to identify the operative oxygen evolution pathway for each of these anodes. In addition, steady-state polarisation measurements were used to quantify and compare the OER catalytic activity of electrodes at a given applied potential. Electrochemical impedance spectroscopy (EIS) measurements have demonstrated that the OER Tafel slope, derived from dc or ac measurements are truly characteristic of the kinetics of the reaction. Physical, elemental and morphological characterisation gave further insight into the nature of the modified film surface and enabled one to relate the electrocatalytic activity of these anodes with physical aspects such as surface morphology and surface composition. It was also noted that knowledge of the chemical and structural properties of the underlying oxide phase is crucial in understanding the OER; the amphoteric character of the anodic oxides implies that it is more realistic to investigate the oxygen evolution active sites in terms of anionic surface complexes rather than using the traditional viewpoint of stoichiometric units of the bulk oxide material. We noted that the chemistry of the surfaquo group determines the chemistry of the OER active catalytic site. Concluding, this work has demonstrated that manganese and nickel cobalt mixed oxides display very promising potential as inexpensive materials for electrochemical oxygen evolution in alkaline solutions… Advisors/Committee Members: Lyons, Michael.

Subjects/Keywords: Oxygen Evolution Reaction; Transition metal oxides; Catalysis; OER; Energy

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APA (6^th Edition):

ROMERAL FERNANDEZ, L. A. (2019). Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution. (Thesis). Trinity College Dublin. Retrieved from http://hdl.handle.net/2262/89088

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

ROMERAL FERNANDEZ, LUIS ANDRES. “Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution.” 2019. Thesis, Trinity College Dublin. Accessed January 24, 2021. http://hdl.handle.net/2262/89088.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

ROMERAL FERNANDEZ, LUIS ANDRES. “Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution.” 2019. Web. 24 Jan 2021.

Vancouver:

ROMERAL FERNANDEZ LA. Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution. [Internet] [Thesis]. Trinity College Dublin; 2019. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/2262/89088.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

ROMERAL FERNANDEZ LA. Electrochemical Studies of the Oxygen Evolution Reaction at Mn, Ni/Co Mixed Oxide Electrodes in Aqueous Alkaline Solution. [Thesis]. Trinity College Dublin; 2019. Available from: http://hdl.handle.net/2262/89088

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Arizona

27. Rajaseelan, Rajaratnam Edward. Molybdenum, tungsten and rhodium complexes of nitrogen-oxides.

Degree: 1989, University of Arizona

URL: http://hdl.handle.net/10150/184733

► Complexes of the type MX(η²-NO₃)(CO)₂(PPh₃)₂, (M = Mo, X = Cl, Br; M = W, X = Br) were prepared from the reactions of MX₂(CO)₂(PPh₃)₂… (more)

Subjects/Keywords: Transition metal complexes.; Nitrogen oxides.

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APA (6^th Edition):

Rajaseelan, R. E. (1989). Molybdenum, tungsten and rhodium complexes of nitrogen-oxides. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/184733

Chicago Manual of Style (16^th Edition):

Rajaseelan, Rajaratnam Edward. “Molybdenum, tungsten and rhodium complexes of nitrogen-oxides. ” 1989. Doctoral Dissertation, University of Arizona. Accessed January 24, 2021. http://hdl.handle.net/10150/184733.

MLA Handbook (7^th Edition):

Rajaseelan, Rajaratnam Edward. “Molybdenum, tungsten and rhodium complexes of nitrogen-oxides. ” 1989. Web. 24 Jan 2021.

Vancouver:

Rajaseelan RE. Molybdenum, tungsten and rhodium complexes of nitrogen-oxides. [Internet] [Doctoral dissertation]. University of Arizona; 1989. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/10150/184733.

Council of Science Editors:

Rajaseelan RE. Molybdenum, tungsten and rhodium complexes of nitrogen-oxides. [Doctoral Dissertation]. University of Arizona; 1989. Available from: http://hdl.handle.net/10150/184733

University of Edinburgh

28. Markkula, Mikael. Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides.

Degree: PhD, 2013, University of Edinburgh

URL: http://hdl.handle.net/1842/8061

► Transition metal oxides have been extensively studied during past decades. The purpose of this research was to synthesize new or little characterised transition metal oxides… (more)

▼ Transition metal oxides have been extensively studied during past decades. The purpose of this research was to synthesize new or little characterised transition metal oxides using high-pressure/high-temperature (HPHT) techniques. Various ternary vanadium oxides have been synthesised at ambient and high pressure conditions. All compounds have been studied by neutron and laboratory X-ray powder diffraction and magnetisation measurements. In some cases resistivity and synchrotron X-ray powder diffraction measurements were also carried out. The MnVO3 perovskite containing localized 3d5 Mn2+ and itinerant 3d1 V4+ states has been synthesised at 8 GPa and 1100°C. MnVO3 crystallises in Pnma space group (a = 5.2741(6) Å, b = 7.4100(11) Å, and c = 5.1184(8) Å at 300 K) and is metallic at temperatures of 2 – 300 K and at pressures of up to 67 kbar. Synchrotron X-ray powder diffraction study on the combined sample of several high pressure products showed slight variation in the stoichiometry of MnVO3. Incommensurate Mn spin order was discovered in the neutron powder diffraction measurements, which reveal a (0.29 0 0) magnetic vector below the 46 K spin ordering transition, and both helical and spin density wave orderings are consistent with the diffraction intensities. Electronic structure calculations show large exchange splittings of the Mn and V 3d bands, and (kx 0 0) crossings of the Fermi energy by spin up and down V 3d bands may give rise to Ruderman-Kittel-Kasuya-Yosida coupling of Mn moments, in addition to their superexchange interactions. The new compound CoVO4 has been discovered in a high pressure synthesis experiment. Magnetic susceptibility measurement, synchrotron X-ray and neutron powder diffraction studies were carried out. Refinements of the synchrotron X-ray and neutron data show CoVO4 to crystallise in space group Pbcn (a = 4.5012(2) Å, b = 5.5539(3) Å, and c = 4.8330(2) Å at 300 K (synchrotron X-ray data)). The magnetic susceptibility measurement reveals that Co3+ is most likely in a low spin state in CoVO4. Monoclinic brannerite type CoV2O6 was synthesised in ambient pressure. Neutron powder diffraction measurements were carried out and an antiferromagnetic order with an a x b x 2c supercell was observed below TN = 15 K. High spin Co2+ moments of magnitude 4.77(4) μB at 4 K lie in the ac plane and are ferromagnetically coupled within chains of edge-sharing CoO6 octahedra parallel to b axis. No structural transition is observed down to 4 K, but a magnetostriction accompanying antiferromagnetic order at TN = 15 K was discovered. A field-induced 1/3 magnetisation plateau and corresponding changes in the magnetic structure were studied by carrying out neutron powder diffraction measurements at 2 K in applied magnetic fields of 0, 2.5 and 5.0 T. Three collinear magnetic phases were observed as field increases; the above antiferromagnetic state with propagation vector (0 0 ½), a ferrimagnetic (¯⅓ 1 ⅓) phase, and a (0 0 0) ferromagnetic order. Co2+ moments of 4.4 - 5.0 μB have a large orbital component and are…

Subjects/Keywords: 546; HPHT; high-pressure/high-temperature; transition metal oxides

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Markkula, M. (2013). Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/8061

Chicago Manual of Style (16^th Edition):

Markkula, Mikael. “Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides.” 2013. Doctoral Dissertation, University of Edinburgh. Accessed January 24, 2021. http://hdl.handle.net/1842/8061.

MLA Handbook (7^th Edition):

Markkula, Mikael. “Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides.” 2013. Web. 24 Jan 2021.

Vancouver:

Markkula M. Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides. [Internet] [Doctoral dissertation]. University of Edinburgh; 2013. [cited 2021 Jan 24]. Available from: http://hdl.handle.net/1842/8061.

Council of Science Editors:

Markkula M. Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides. [Doctoral Dissertation]. University of Edinburgh; 2013. Available from: http://hdl.handle.net/1842/8061

Louisiana State University

29. Saghayezhian, Mohammad. Manipulating physical properties of complex materials by processing.

Degree: PhD, Physical Sciences and Mathematics, 2017, Louisiana State University

URL: etd-04042017-163117 ; https://digitalcommons.lsu.edu/gradschool_dissertations/4269

► Transition metal oxides (TMOs) are a class of materials in which charge, orbital, spin and lattice strongly interact with each other. In the present thesis,… (more)

▼ Transition metal oxides (TMOs) are a class of materials in which charge, orbital, spin and lattice strongly interact with each other. In the present thesis, a special attention is paid to the physical properties of TMOs as a function of processing. First, TMOs are studied as substrates, where the surface is of prime importance. Second, the thin films are fabricated and their physical properties are presented. The SrTiO3 (001) and (111) surfaces are weakly and strongly polar and the free energy of intact surfaces should diverge. It is shown that in TiO2 terminated SrTiO3(001) the top most layer shows rumpling of O and Ti atoms. Rearrangement of atoms at the surface is one way of minimizing the surface free energy and avoiding polar catastrophe. In the case of SrTiO3 (111), we have systematically investigated the annealing effect on the structure and composition of the polar surface of SrTiO3(111). Heteroepitaxial growth of transition-metal oxide films on the open (111) surface of SrTiO3results in significant restructuring due to the polar mismatch. Using processing condition that we found for SrTiO3 (111), we have solved the polar catastrophe issue that occurs between materials with polar mismatch. we have studied La0.66Sr0.33MnO3 (001) under specific processing conditions and found a new interfacial magnetic interaction which is primarily driven by broken symmetry in oxide heterostructures. We show direct evidence that the symmetry breaking between conventional ferromagnetic metal and diamagnetic band insulator leads to dramatic modification of structure and chemistry at the interface. As a result, antiferromagnetic coupling emerges at the interface region which leads to spontaneous magnetic reversal and inverted hysteresis persisting well above room temperature. By further processing the La1-xSrxMnO3-y (001) thin films, it was shown that fine control of growth parameters can drastically change the physical properties of transition metal oxides. Magnetic properties of La1-xSrxMnO3-y was shown to differ from the target material La0.66Sr0.33MnO3 Appearance of exchange bias, inverted hysteresis and spontaneous magnetic reversal once more show that intimate competition in electronic, spin and lattice degrees of freedom in transition metal oxides can lead to new functionality, even in a monolithic thin film.

Subjects/Keywords: Polar surfaces and interfaces; magnetic materials; thin films; transition metal oxides

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APA (6^th Edition):

Saghayezhian, M. (2017). Manipulating physical properties of complex materials by processing. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-04042017-163117 ; https://digitalcommons.lsu.edu/gradschool_dissertations/4269

Chicago Manual of Style (16^th Edition):

Saghayezhian, Mohammad. “Manipulating physical properties of complex materials by processing.” 2017. Doctoral Dissertation, Louisiana State University. Accessed January 24, 2021. etd-04042017-163117 ; https://digitalcommons.lsu.edu/gradschool_dissertations/4269.

MLA Handbook (7^th Edition):

Saghayezhian, Mohammad. “Manipulating physical properties of complex materials by processing.” 2017. Web. 24 Jan 2021.

Vancouver:

Saghayezhian M. Manipulating physical properties of complex materials by processing. [Internet] [Doctoral dissertation]. Louisiana State University; 2017. [cited 2021 Jan 24]. Available from: etd-04042017-163117 ; https://digitalcommons.lsu.edu/gradschool_dissertations/4269.

Council of Science Editors:

Saghayezhian M. Manipulating physical properties of complex materials by processing. [Doctoral Dissertation]. Louisiana State University; 2017. Available from: etd-04042017-163117 ; https://digitalcommons.lsu.edu/gradschool_dissertations/4269

Indian Institute of Science

30. Choudhury, Debraj. Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides.

Degree: PhD, Faculty of Science, 2013, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/1923

► Disorder in materials often brings in new and exotic physical properties along with it. It is thus very important to study different kinds of disorder… (more)

▼ Disorder in materials often brings in new and exotic physical properties along with it. It is thus very important to study different kinds of disorder and their implications on various material properties. In this thesis, we study selected transition metal oxide families of compounds, each being associated with a specific kind of disorder and investigate effects of that disorder on their dielectric and magnetic properties. In Chapter1, we have given brief introductions on the origin of magnetic and dielectric properties in materials and have also discussed various mechanism which give rise to multiferroism in materials which exhibit both spontaneous magnetic ordering and spontaneous electric ordering in the same phase of the material. In Chapter2,we describe the various methodologies adopted in this thesis. In Chapter3,we mainly study the effect of cationic size-disorder in deciding un-usually robust dielectric properties of Ln2CuTiO6(Ln=Y,Dy,Ho,Er,Yb) family of compounds. We discover that these materials, in addition to possessing large dielectric constant values, also exhibit exceptional stabilities of their dielectric constants with respect to large changes in temperature and frequency. We further find that this class of materials are non-ferroelectrics though its hares the same non-centrosymmetric space group, P63cm,with the well-known multiferroic YMnO3 that undergoes a ferroelectric transition at 940K. Using first principles calculations, we establish that exceptional dielectric properties result from a combination of two separate effects. Extensive size disorders at the Cu/Ti B-site suppress the expected ferroelectric transition, leading to relatively large values of the dielectric constant for every compound investigated in this series. Additionally, it is shown that the majority contribution to the dielectric constant arises from intermediate-frequency polar vibrational modes, making it relatively stable against temperature variations. In Chapter4, we study the effect of cation anti-site disorder on the magnetic, electric and dielectric properties of the solid solution series of (x)Fe2O3-(1-x)FeTiO3 for several values of x. For intermediate values of x, these solid solution members are found to be strong ferrimagnets. Anti-site cation disorder, between Fe and Ti, however strongly reduces the magnetic moment values. By tuning the degree of cation anti-site disorder, we attain multi-functionality in these samples. We have performed detailed characterizations of valence states of Fe and Ti across the solid solution series using x-ray photoelectron spectroscopy and x-ray absorption spectroscopy. Using x-ray magnetic circular dichroism, we validate the microscopic model of magnetism and suggest a microscopic picture of the anti-site cation disorder for these samples. In Chapter5,we study the effects of controlled chemical disorder in SrTiO3 lattice, by performing site-specific doping of Mn in SrTiO3. We find that site specific Mn doping has decisive influence on their dielectric properties with qualitatively and… Advisors/Committee Members: Sarma, D D (advisor), Krishnamurthy, H R (advisor).

Subjects/Keywords: Transition Metal Oxides; Ferromagnetism; Magnetism; Dielectric Properties; SrTiO3; La2NiMnO6; Inorganic Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Choudhury, D. (2013). Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/1923

Chicago Manual of Style (16^th Edition):

Choudhury, Debraj. “Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides.” 2013. Doctoral Dissertation, Indian Institute of Science. Accessed January 24, 2021. http://etd.iisc.ac.in/handle/2005/1923.

MLA Handbook (7^th Edition):

Choudhury, Debraj. “Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides.” 2013. Web. 24 Jan 2021.

Vancouver:

Choudhury D. Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2013. [cited 2021 Jan 24]. Available from: http://etd.iisc.ac.in/handle/2005/1923.

Council of Science Editors:

Choudhury D. Effects Of Disorder On Physical Properties Of Selected Transition Metal Oxides. [Doctoral Dissertation]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ac.in/handle/2005/1923

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