CoMnFe hydroxysulfide nanowire@Ni(OH)2 nanorod arrays as self-supporting electrodes for high-efficiency oxygen evolution reaction

Abstract

Developing cost-effective and highly active catalysts for water oxidation plays a paramount role in water electrolysis. By assembling diversiform components with particular features and tuning microstructure on micrometer and nanometer of catalysts felicitously, a huge optimization on its electrochemical performance can be possible. In this work, we report an effective three-dimensional (3D) electrode comprising of hierarchical core–shell structure on conductive nickel foam, in which ultrafine Ni(OH)2 nanorods are directly grown on the CoMnFe hydroxysulfide nanowires via a three-step facile synthesis. Benefitting from the prominent structural advantages and desirable compositions, several crucial factors conducive to excellent catalytic behavior, including big surface area, highly exposed surface active sites, rapid ionic and electronic transport and open-channels for effective gas releasing, are endowed to the electrocatalyst. Therefore, the resultant CoMnFe hydroxysulfide nanowire@Ni(OH)2 nanorod nanoarrays exhibit a superior catalytic performance (η = 264 mV@200 mA cm−2) for water oxidation, with a low Tafel slope of 73 mV dec−1, and a long-term durability for at least 100 h in the alkaline electrolyte. This work broadens the horizon and displays a fresh strategy for the suitable design of efficient oxygen evolution reaction (OER) electrocatalysts with new hierarchical hybrid structure.