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University of Oxford

1. Chan, Chun Wong Aaron. Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis.

Degree: PhD, 2012, University of Oxford

Surface catalysed reactions play an important role in chemical productions. Developments of catalyst requiring high activity whilst improving on product selectivity can potentially have a profound effect in the chemical industry. Traditional catalyst modifications were focused on tuning the size, shape and foreign metal doping to form well defined metal nanoparticles of unique functionalities. Here, we show new approach to engineering of metal nanocatalysts via a subsurface approach can modify the chemisorption strength of adsorbates on the surface. Carbon modified nanoparticles were synthesised using glucose to stabilise Pd nanoparticles at a molecular level. Upon heat treatment, the carbonised glucose encapsulated the Pd nanoparticles with carbon atoms take residence in the octahedral holes (15 at.%). These materials were tested in liquid phase stereoselective hydrogenations of 3-hexyn-1-ol and 4-octyne. The former has importance in the fragrance industry towards the production of leaf fragrance alcohol. It was shown for the first time that the geometrically and electronically modified Pd with interstitial carbon atoms reduced the adsorption energy of alkenes, ultimately leading to higher reaction selectivity. Boron modified Pd nanoparticles was synthesised using BH3.THF in the liquid phase. The material possess high B interstitial saturation (20 at.%), which can be synthesised for the first time below 100°C. These materials were tested in the liquid phase selective hydrogenation of various alkynes and 2-chloronitrobenzene, of which the latter has importance in the pesticides industry. Kinetic modelling on the hydrogenation of 4-octyne suggests these subsurface occupied B does play a pivotal role on increasing the reaction selectivity, as removal of these species lead to decreased selectivity. Au nanoparticles were synthesised and characterised using H13COOH NMR. The new liquid NMR characterisation method is successfully applied to examine the chemisorption strength of metal nanoparticles. An attempt to synthesise PVP capped B modified Pd nanoparticles with the above NMR characterisation was investigated. It is believed the examples of subsurface atom modifications as shown here may offer future catalyst developments in this area.

Subjects/Keywords: 541; Inorganic chemistry; Nanomaterials; Surface chemistry; Surface analysis; heterogeneous catalyst; selective hydrogenation; liquid phase; subsurface; interstitial; alkynes; kinetic modelling; 2-chloronitrobenzene; formic acid; nuclear magnetic resonance

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

APA (6th Edition):

Chan, C. W. A. (2012). Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:866296af-5296-4d2e-8e52-6499dacaef0f ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.647518

Chicago Manual of Style (16th Edition):

Chan, Chun Wong Aaron. “Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis.” 2012. Doctoral Dissertation, University of Oxford. Accessed March 04, 2021. http://ora.ox.ac.uk/objects/uuid:866296af-5296-4d2e-8e52-6499dacaef0f ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.647518.

MLA Handbook (7th Edition):

Chan, Chun Wong Aaron. “Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis.” 2012. Web. 04 Mar 2021.

Vancouver:

Chan CWA. Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis. [Internet] [Doctoral dissertation]. University of Oxford; 2012. [cited 2021 Mar 04]. Available from: http://ora.ox.ac.uk/objects/uuid:866296af-5296-4d2e-8e52-6499dacaef0f ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.647518.

Council of Science Editors:

Chan CWA. Ultraselective nanocatalysts in fine chemical and pharmaceutical synthesis. [Doctoral Dissertation]. University of Oxford; 2012. Available from: http://ora.ox.ac.uk/objects/uuid:866296af-5296-4d2e-8e52-6499dacaef0f ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.647518

2. Saint-Aubin, Christine de. Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate.

Degree: Docteur es, Chimie des matériaux, 2013, Mulhouse

Cette thèse propose tout d’abord une méthode originale, appelée 2 en 1, de construction contrôlée, couche-par-couche, de films de polyélectrolytes, basée sur le dépôt d’un unique complexe polycation-polyanion. Détaillée dans le cas du poly(éthylènedioxythiophène)-poly(styrènesulfonate) PEDOT-PSS, la méthode est ensuite étendue avec le même succès à d’autres complexes (poly(éthylèneimine) branché-poly(4 styrènesulfonate), poly(diallyldiméthylammonium)-poly(4 styrènesulfonate) et poly(allylamonium)-poly(4 styrènesulfonate)).Les films 2 en 1 de PEDOT PSS sont robustes vis-à-vis d’un recuit thermique et possèdent une conductivité électronique indépendante de leur épaisseur. Cette conductivité peut être améliorée en utilisant un composite contenant des nanoparticules d’or Au Np PEDOT PSS. Des superstructures alternant dépôts de PEDOT PSS et de composite ont, en outre, pu être construites.La construction est contrôlée non seulement sur des substrats rigides (verre, wafer de silicium) mais également sur des substrats élastomère de type silicone (polydiméthylsiloxane PDMS). Le traitement du PDMS par polymérisation plasma d’EDOT sous vide permet le dépôt subséquent de films 2 en 1 de PEDOT PSS. Par ailleurs, la pulvérisation cathodique d’or sur le PDMS permet d’obtenir des conducteurs étirables, de surcroît utilisables comme substrats de films 2 en 1 de PEDOT PSS.Enfin, de nouveaux complexes aqueux synthétisés par voie chimique à partir d’EDOT et d’un polysaccharide (sulfate de chondroïtine A) ont conduit à des films présentant une très bonne conduction qui peut être augmentée par inclusion de nanoparticules d’or. Ces nouveaux composés sont porteurs d’un potentiel très prometteur.

This thesis proposes firstly an original method, called 2 in 1 method, for controlled, layer-by-layer, polyelectrolytes film buildup, based on the deposition of a sole polycation-polyanion complex. Detailed on the case of poly(ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS), the method was then extended with the same success to other complexes (branched poly(ethyleneimine)-poly(4 styrenesulfonate), poly(diallyldimethylammonium)-poly(4 styrenesulfonate) and poly(allylamonium)-poly(4 styrenesulfonate)).The 2 in 1 PEDOT PSS films are robust regarding thermal annealing and have an electronic conductivity independent of their thickness. This conductivity can be improved by using a composite containing gold nanoparticles Au Np PEDOT PSS. Superstructures alternating PEDOT PSS and composite depositions were also obtained.Film buildup is controlled not only on rigid substrates (glass, silicon wafer) but also on elastomeric substrates of the silicon type (polydimethylsiloxane PDMS). The treatment of PDMS by vacuum plasma enhanced chemical vapor deposition (PECVD) of EDOT allows subsequent deposition of 2 in 1 PEDOT-PSS films. Besides, gold sputter deposition on PDMS reaches stretchable conductors. Gold sputtered PDMS can further act as a substrate for 2 in 1 PEDOT-PSS films.Finally, new aqueous complexes, chemically synthesized from EDOT and a…

Advisors/Committee Members: Vallat, Marie-France (thesis director), Schaff, Pierre (thesis director), Nardin, Michel (thesis director).

Subjects/Keywords: Multicouches; Polyélectrolytes; Méthode 2-en-1; PEDOT-PSS; Électronique déformable; Polymérisation plasma EDOT; Polysaccharides; Biomatériaux; Multilayers; Polyelectrolytes; 2-in-1 method; PEDOT-PSS; Stretchable electronics; EDOT plasma polymerization; Polysaccharides; Biomaterials; 541

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

APA (6th Edition):

Saint-Aubin, C. d. (2013). Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate. (Doctoral Dissertation). Mulhouse. Retrieved from http://www.theses.fr/2013MULH8652

Chicago Manual of Style (16th Edition):

Saint-Aubin, Christine de. “Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate.” 2013. Doctoral Dissertation, Mulhouse. Accessed March 04, 2021. http://www.theses.fr/2013MULH8652.

MLA Handbook (7th Edition):

Saint-Aubin, Christine de. “Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate.” 2013. Web. 04 Mar 2021.

Vancouver:

Saint-Aubin Cd. Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate. [Internet] [Doctoral dissertation]. Mulhouse; 2013. [cited 2021 Mar 04]. Available from: http://www.theses.fr/2013MULH8652.

Council of Science Editors:

Saint-Aubin Cd. Conception de nouveaux matériaux conducteurs extensibles à base de multicouches de polyélectrolytes sur support silicone : Conception of new stretchable conducting materials based on polyelectrolyte multilayers on silicon substrate. [Doctoral Dissertation]. Mulhouse; 2013. Available from: http://www.theses.fr/2013MULH8652

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