Researchers at the Indian Institute of Technology Guwahati (IIT-G) have developed a cost-effective alternative to the Photo-Electro-Chemical (PEC) cells that split water molecules to harness hydrogen. The team is developing novel materials that can use sunlight to split water into hydrogen and oxygen. The materials are much cheaper than the currently used 'noble metals', leading to cost-effective solar-powered hydrogen generators. The team aims to pave the way to a carbon-free hydrogen economy.
The team of IIT Guwahati scientists has developed non-noble metal catalysts that are as good as the expensive metals in splitting water into PEC cells. "We have developed a ternary catalyst that comprises cobalt-tin layered-double hydroxides (LDH) and bismuth vanadate, which forms a p-n junction semiconductor with graphene bridges, and have shown that the catalyst, when used as a photoanode, is able to split water easily to produce hydrogen and oxygen," said lead researcher Dr Mohammad Qureshi, Professor, Department of Chemistry, IIT Guwahati.
Graphene siphons the holes away from the vanadate and transports them into the cobalt-tin LDH, thus preventing their recombination with the electrons. The holes and the electrons are now available to split the water into hydrogen and oxygen.