New routes to catalysts for green hydrogen
Growing global energy demand and geopolitical instability in Europe have intensified interest in reducing dependence on fossil fuels and developing renewable energy sources. Electrochemical energy conversion and storage, including fuel cells, water electrolysis and batteries, are central to this transition. Hydrogen stands out as a promising energy carrier for a sustainable, carbon-neutral economy.
Water electrolysis can produce green hydrogen when powered by renewable electricity. It involves two coupled reactions: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Advanced catalysts for these reactions are based on platinum and iridium, respectively. Because both metals are expensive and scarce, reducing their use while maintaining catalyst performance is essential to the economic viability of water electrolysis.
RadHydroCats aims to develop high-entropy alloys (HEAs) as advanced electrocatalysts for water electrolysis using a new radiolytic synthesis method. This gamma-irradiation approach enables synthesis at atmospheric pressure and room temperature and offers an environmentally favourable alternative to conventional physical or chemical methods.
Combining multiple elements in HEAs creates opportunities for new catalytic sites tailored to specific reactions, with the potential for high catalytic efficiency. The project brings together experimental and theoretical approaches to the rational design and synthesis of HEAs for HER and OER.
A central aim is to minimise the use of precious metals, such as platinum (Pt), iridium (Ir) and ruthenium (Ru), by combining them with more abundant transition metals: iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), chromium (Cr), manganese (Mn), molybdenum (Mo), vanadium (V) and zinc (Zn).
The resulting alloys will be deposited on high-surface-area carbon and titanium oxynitride supports. This approach aims to maximise the number of active sites and further improve catalyst activity and stability.