Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.647781
Title: Oxygen evolution electrocatalysts for proton exchange membrane water electrolysis
Author: Richardson, Peter
ISNI:       0000 0004 5346 9603
Awarding Body: University of Southampton
Current Institution: University of Southampton
Date of Award: 2015
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Abstract:
Proton exchange membrane (PEM) water electrolysers are forecast to become an important intermediary energy storage technology between renewable power sources and energy distribution/usage. This is because they offer a production route to high purity H2 that is both non-polluting and efficient. Energy stored as H2 can be converted back to electricity for use in the national grid, pumped into existing natural gas networks or used as a fuel for hydrogen-powered vehicles. The majority of the energy losses in a PEM water electrolyser are associated with the high overpotential that is required for the electrochemical evolution of O2 that occurs at the anode. The highly oxidising conditions of this reaction coupled to the low pH of the PEM environment restrict electrocatalyst selection to expensive noble metal oxides. Thus to enhance the commercial viability of PEM electrolysers, the goal of electrocatalyst development for the O2 evolution reaction is to (i) increase the catalytic performance, (ii) increase the catalyst stability and (iii) reduce the cost of the catalyst components. In this work a range of iridium-based electrocatalysts with reduced Ir contents have been prepared. Two methods are employed to reduce the Ir content: (i) mixing the Ir with ruthenium to form a binary metal oxide and (ii) dispersing the active Ir phase on an indium tin oxide (ITO) support. Investigation of the electrocatalysts via a combination of different physical and electrochemical characterisation techniques, including a novel in-situ X-ray absorbance experiment, indicates that both approaches produce electrocatalysts with comparable or improved O2 evolution activity compared to the state-of-the-art iridium oxide (IrO2) material. However selection of the most appropriate catalyst for PEM electrolysis may ultimately be a compromise between activity, stability and cost.
Supervisor: Russell, Andrea Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.647781  DOI: Not available
Keywords: QD Chemistry
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