Bimetallic catalyst

Material scientists at Washington University in St Louis (WUSTL) have developed a bimetallic fuel-cell catalyst that is two to five times more effective than commercial catalysts.

Dr Younan Xia, the James M McKelvey Professor of Biomedical Engineering at WUSTL, led a team of scientists at the university and the Brookhaven National Laboratory in developing the bimetallic catalyst, which is comprised of a palladium core or 'seed' that supports dendritic platinum branches, or arms, that are fixed on the nanostructure.

They synthesised the catalysts by sequentially reducing precursor compounds to palladium and platinum with L-ascorbic acid in an aqueous solution. The catalysts have a high surface area, invaluable for a number of applications besides fuel cells, and are robust and stable.

Xia and his team tested how the catalysts performed in the oxygen reduction reaction process in a fuel cell, which determines how large a current will be generated in an electrochemical system.