Graphene-based catalyst for fuel cells
doi:10.1038/nindia.2017.5 Published online 17 January 2017
Researchers have developed a graphene catalyst which has potential for making fuel cells. The silver-nanowire-decorated boron-doped graphene catalyst that helps convert electrochemical energy to electricity1.
An important reaction in fuel cells is the oxygen reduction reaction, which is often slow. The need for platinum-based catalysts also makes fuel cells expensive.
To prepare a cheap and efficient catalyst, scientists from CSIR-Central Electrochemical Research Institute (CSIR-CECRI), Tamil Nadu and Mahatma Gandhi University in Kerala deposited silver nanowire on boron-doped graphene sheets. They then tested its efficiency in speeding oxygen reduction reaction in fuel cells.
The catalyst-incorporated fuel cells showed a very high onset potential and current density. Its efficiency was comparable to that of commercially available platinum-based catalysts.
The catalyst contained porous channels which allowed the transport of oxygen gas and hydroxyl ions during the reaction. It also exhibited stability over a period of seven hours with a low yield of hydrogen peroxide known to disrupt oxygen reduction reaction in fuel cells.
“The method provides a way to develop a low-cost and thermally stable catalyst as an efficient alternative to platinum-based fuel-cell catalysts,” says lead researcher Subbiah Alwarappan from the CSIR-CECRI.
1. Nair, A. K. et al. Boron doped graphene wrapped silver nanowires as an efficient electrocatalyst for molecular oxygen reduction. Sci. Rep. 6, 37731 (2016)