Metal-free graphene catalyst for green energy
doi:10.1038/nindia.2015.152 Published online 19 November 2015
Researchers have synthesized nitrogen-doped fluorinated graphene, which can catalyse the oxygen reduction reaction1. This catalyst is potentially useful for catalyzing the oxygen reduction reaction in fuel cells and metal-air batteries.
Platinum-based catalysts are widely used in fuel cells, but they are expensive and slow down the oxygen reduction reaction.
To make a better catalyst for the oxygen reduction reaction, the researchers doped fluorinated graphene by thermally treating it in the presence of the nitrogen-containing compound melamine. They then probed the efficiency of the catalyst to reduce oxygen and compared it with those of other catalysts such as graphene, nitrogen-doped graphene and fluorinated graphene.
In electrochemical measurements, the new catalyst displayed a very high potential for the oxygen reduction reaction that was slightly higher than those of the other graphene-based catalysts.
The oxygen reduction reaction current of nitrogen-doped fluorinated graphene was also higher than that of other catalysts over the entire potential range. This indicates that the new catalyst catalyses the oxygen reduction reaction more effectively than the other catalysts.
“Besides facilitating high electron transfer, the nitrogen-doped fluorinated graphene exhibited excellent stability, opening up a new avenue for developing metal-free catalysts for energy-producing technologies,” says lead researcher Subbiah Alwarappan.
1. Vineesh, T. V. et al. Synergistic effects of dopants on the spin density of catalytic active centres of N-doped fluorinated graphene for oxygen reduction reaction. Appl. Mater. Today 1, 74−79 (2015)