Boosting Electrocatalytic Oxygen Evolution over Ce−Co₉S₈ Core–Shell Nanoneedle Arrays by Electronic and Architectural Dual Engineering.

Liu, Kun; Zhu, Zhuoya; Jiang, Mengqi; Li, Liangcheng; Ding, Linfei; Li, Meng; Sun, Dongmei; Yang, Gaixiu; Fu, Gengtao; Tang, Yawen

An dual electronic and architectural engineering strategy is a good way to rationally design earth‐abundant and highly efficient electrocatalysts of the oxygen evolution reaction (OER) for sustainable hydrogen‐based energy devices. Here, a Ce‐doped Co9S8 core–shell nanoneedle array (Ce−Co9S8@CC) supported on a carbon cloth has been designed and developed to accelerate the sluggish kinetics of the OER. Profiting from valance alternative Ce doping, a fine core–shell structure and vertically aligned nanoneedle arrayed architecture, Ce−Co9S8@CC integrates modulated electronic structure, highly exposed active sites, and multidimensional mass diffusion channels; together, these afford a favorable catalyzed OER. Ce−Co9S8@CC exhibits remarkable performance in the OER in an alkaline medium, where the overpotential requires only 242 mV to deliver a current density of 10 mA cm−2 for the OER; this is 70 mV superior to that of Ce‐free Co9S8 catalyst and other counterparts. Good stability and impressive selectivity (nearly 100 % Faradic efficiency) are also demonstrated. When integrated into a two‐electrode OER//HER electrolyzer, the as‐prepared Ce−Co9S8@CC displays a low operation potential of 1.54 V at 10 mA cm−2 and long‐term stability, thus demonstrating great potential for economical water electrolysis.

HYDROGEN evolution reactions; ARCHITECTURAL engineering; OXYGEN evolution reactions; WATER electrolysis; ELECTRONIC structure; OXYGEN; ELECTROCATALYSTS

Chemistry - A European Journal, 2022, Vol 28, Issue 32, p1

0947-6539

Academic Journal

10.1002/chem.202200664