ZHANG Yun, HU Jin-Song, JIANG Wen-Jie, GUO Lin, WEI Zi-Dong, WAN Li-Jun
J. Electrochem., 2014, 20, 401-409
Abstract (click image for pdf file)
Developing low-cost catalysts with high electrocatalytic activity for oxygen reduction reaction (ORR) has recently attracted much attention because the sluggish ORR currently limits the performance and commercialization of fuel cells and metal-air batteries as well. Nitrogen doped carbon materials have been considered as a promising candidate for the replacement of high-cost and scarce Pt-based catalysts although their electrocatalytic activity still needs to be much improved. In this work, an improved nitrogen-doped graphene/carbon nanotubes composite (N-rGO/CNT) was developed as an efficient ORR electrocatalyst. It was found that the ORR activity of N-rGO/CNT composite could be significantly enhanced by introducing iron in nitrogen-doping process, and further boosted by constructing nanopores in catalysts for allowing more catalytically active sites accessible and enhancing mass transfer. Moreover, the electrochemical measurement showed that the improved catalysts exhibited superior tolerance to methanol crossover and durability, indicating their potential as ORR catalysts for energy conversion and storage applications. |