Spontaneously separated intermetallic Co3Mo from nanoporous copper as versatile electrocatalysts for highly efficient water splitting

• Published in: Nature communications Vol. 11; no. 1; pp. 2940 - 10
• Main Authors: Shi, Hang, Zhou, Yi-Tong, Yao, Rui-Qi, Wan, Wu-Bin, Ge, Xin, Zhang, Wei, Wen, Zi, Lang, Xing-You, Zheng, Wei-Tao, Jiang, Qing
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 10.06.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 140/133; 140/146; 147/135; 147/137; 147/143; 639/301/299/886; 639/4077/909; 639/638/77/884; Catalysis; Catalysts; Copper; Electrocatalysts; Electrochemistry; Energy conversion; Energy conversion efficiency; Evolution; Humanities and Social Sciences; Hydrogen; Hydrogen evolution reactions; Hydrogen production; Hydrogen-based energy; Hydroxylation; Intermediates; Ion transport; multidisciplinary; Noble metals; Oxidation; Oxygen; Oxygen evolution reactions; Science; Science (multidisciplinary); Splitting; Water splitting
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-16769-6

Developing robust nonprecious electrocatalysts towards hydrogen/oxygen evolution reactions is crucial for widespread use of electrochemical water splitting in hydrogen production. Here, we report that intermetallic Co 3 Mo spontaneously separated from hierarchical nanoporous copper skeleton shows genuine potential as highly efficient electrocatalysts for alkaline hydrogen/oxygen evolution reactions in virtue of in-situ hydroxylation and electro-oxidation, respectively. The hydroxylated intermetallic Co 3 Mo has an optimal hydrogen-binding energy to facilitate adsorption/desorption of hydrogen intermediates for hydrogen molecules. Associated with high electron/ion transport of bicontinuous nanoporous skeleton, nanoporous copper supported Co 3 Mo electrodes exhibit impressive hydrogen evolution reaction catalysis, with negligible onset overpotential and low Tafel slope (~40 mV dec −1 ) in 1 M KOH, realizing current density of −400 mA cm −2 at overpotential of as low as 96 mV. When coupled to its electro-oxidized derivative that mediates efficiently oxygen evolution reaction, their alkaline electrolyzer operates with a superior overall water-splitting output, outperforming the one assembled with noble-metal-based catalysts. Electrochemical water splitting is an attractive energy conversion technology, but it usually suffers from low efficiency. Here, the authors report intermetallic Co 3 Mo integrated on porous Cu as highly efficient electrocatalysts for alkaline HER/OER due to in-situ hydroxylation and electro-oxidation.