Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5149595 | Journal of Power Sources | 2017 | 9 Pages |
Abstract
Oxygen reduction reaction (ORR) plays an important role in green energy conversion, although catalysts are necessary for overcoming its sluggish kinetic. Herein, a nanocrystal NiCo2O4/N-doped graphene composite material showing high ORR electrocatalytic activity is prepared. The resulting NiCo2O4/N-doped graphene composite (NiCo2O4-NG/C) combines the advantages of both component materials and shows enhanced ORR electrocatalytic activity (i.e., more positive peak potential and half-wave potential compared with NiCo2O4) while having higher diffusion-limited current density values (â5.7 mA cmâ2, 1600 rpm), better tolerance to methanol, and improved stability than 20 wt% Pt/C. NiCo2O4 anchored on N-doped graphene are demonstrated to be nanocrystal with tiny crystalline grain (diameter < 5 nm) and result in large surface area, thereby allowing more active sites to be exposed. Moreover, the potential exposure of high-index planes may be also responsible for the observed high activity of these materials.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Li-li Wan, Guo-long Zang, Xin Wang, Le-an Zhou, Tian Li, Qi-xing Zhou,