Modulated Electronic Structure of Co<sub>3</sub>O<sub>4</sub> by Single Atoms for Efficient Anodic Oxygen Evolution in Acid
Jieyu Yang, Fenghua Xu, Wenli Zhao, Luqiong Liu, Baicheng Weng
Abstract
Abstract The challenge of the practical application of a water electrolyzer system lies in the development of low‐manufacturing cost, highly active, and stable electrocatalysts to replace the noble metal ones, in order to enable environmentally friendly hydrogen production on a large scale. Herein, a facile method is proposed for boosting the performance of Co 3 O 4 through the incorporation of large‐sized single atoms. Due to the larger ionic radius of rare earth metals than that of Co, the incorporation elongates the bond length of Co─O, resulting in the narrowed d‐p band centers and the high spin configuration, which is favorable for the interaction and charge transfer with absorbent (*OH). As a result, the Ce‐incorporated Co 3 O 4 with the longest Co─O bond length exhibits the best oxygen evolution reaction (OER) performance, specifically, the turnover frequency is over 17 times higher than that of pristine Co 3 O 4 nanosheet under an overpotential of 400 mV. Powered by a commercial Si solar cell, a two‐electrode solar water‐splitting device combining Ce‐incorporated Co 3 O 4 and Pt delivers a solar‐to‐hydrogen conversion efficiency of 13.53%. The strategy could provide a new insight for improving the performance of OER electrocatalysts in acid toward practical applications.