The electrochemical / photoelectrochemical production of hydrogen by water electrolysis/photo-electrolysis is a green hydrogen production route that can be powered by sustainable energy sources (solar, wind, wave power). At the same time, if hydrogen is to be established as the fuel of choice, hydrogen electrochemical compression offers an effective and green alternative.
The aim of the present proposal is to develop efficient catalysts/photo-catalysts for hydrogen production by water electrolysis/photo-electrolysis and hydrogen compression-purification. The challenges to address are: a) The high cost of platimum group metals (PGM) electrocatalysts in moderate temperature fuel cells, electrolyzers and electrochemical H2 pumps; b) The efficient use of solar energ, in augmenting water electrolysis; c) The need for H2 compression and purification (to that direction, electrochemical compression offers an efficient alternative to mechanical compressors). Towards the aim of the proposed research the following objectives have been set:
(i) Development of efficient Pt-Ni, Pt-Cu, Ir-Ni, Ir-Cu, Pt-Ti and Ir-Ti cathodes and anodes of minimal precious metal content, by means of a novel galvanic replacement/deposition technique;
(ii) Development of novel TiO2–based photoanodes of improved visible light activity and conductivity by means of hydrothermal/gas-phase synthesis;
(iii) Development of bi-functional IrO2/TiO2 anodes/photoanodes for variable illumination conditions;
(iv) Theoretical prediction of best binary metal/metal oxide catalyst combinations for the relevant hydrogen evolution, oxygen evolution (electrolyzer) and hydrogen oxidation (compressor) reactions;
(v) Testing optimum electrocatalysts/photo-electrocatalysts in electrochemical hydrogen compression cells and water photoelectrolyzers.
(vi) Produce a combined prototype water (photo)electrolysis/ pure hydrogen compression unit.