Metallic Co4N Porous Nanowire Arrays Activated by Surface Oxidation as Electrocatalysts for the Oxygen Evolution Reaction

作者：Pengzuo Chen, Kun Xu, Zhiwei Fang, Yun Tong, Junchi Wu, Xiuli Lu, Peng Xu, Hui Ding, Changzheng Wu, Yi Xie · 发表于：Angewandte Chemie International Edition · 年份：2015 · DOI：10.1002/anie.201506480 · 被引用次数：790 · 研究领域：Electrocatalysts for Energy Conversion、Advanced battery technologies research、Advanced Memory and Neural Computing

Designing highly efficient electrocatalysts for oxygen evolution reaction (OER) plays a key role in the development of various renewable energy storage and conversion devices. In this work, we developed metallic Co4N porous nanowire arrays directly grown on flexible substrates as highly active OER electrocatalysts for the first time. Benefiting from the collaborative advantages of metallic character, 1D porous nanowire arrays, and unique 3D electrode configuration, surface oxidation activated Co4N porous nanowire arrays/carbon cloth achieved an extremely small overpotential of 257 mV at a current density of 10 mA cm(-2), and a low Tafel slope of 44 mV dec(-1) in an alkaline medium, which is the best OER performance among reported Co-based electrocatalysts to date. Moreover, in-depth mechanistic investigations demonstrate the active phases are the metallic Co4N core inside with a thin cobalt oxides/hydroxides shell during the OER process. Our finding introduces a new concept to explore the design of high-efficiency OER electrocatalysts.