Interfacial Sites between Cobalt Nitride and Cobalt Act as Bifunctional Catalysts for Hydrogen Electrochemistry

作者：Fuzhan Song, Wei Li, Jiaqi Yang, Guan‐Qun Han, Tao Yan, Xi Liu, Yi Rao, Peilin Liao, Zhi Cao, Yujie Sun · 发表于：ACS Energy Letters · 年份：2019 · DOI：10.1021/acsenergylett.9b00738 · 被引用次数：182 · 研究领域：Electrocatalysts for Energy Conversion、Fuel Cells and Related Materials、Advanced battery technologies research

Hydrogen (H 2 ) electrochemistry primarily consists of two reactions: hydrogen evolution reaction in water for H 2 production (HER) and hydrogen oxidation reaction in hydrogen fuel cells for H 2 utilization (HOR). The realization of future hydrogen economy necessitates the development of low-cost and competent electrocatalysts for both HER and HOR. Herein, we report that partial nitridation of cobalt nanoparticles on current collectors results in rich Co 2 N/Co interfacial sites, which exhibit bifunctional activity for hydrogen electrochemistry, rivaling the state-of-the-art Pt counterparts tested under similar conditions. Our combined experimental and theoretical computation results demonstrate that Co 2 N/Co interfacial sites not only possess optimal hydrogen adsorption energy but also facilitate water adsorption and dissociation on the catalyst surface, all of which are beneficial to the electrocatalytic performance for both HER and HOR. In addition, our Co 2 N/Co electrocatalysts also demonstrate great tolerance against CO poisoning during long-term H 2 oxidation.