Phase‐Junction Electrocatalysts towards Enhanced Hydrogen Evolution Reaction in Alkaline Media
Qiang Fu, Xianjie Wang, Jiecai Han, Jun Zhong, Tongrui Zhang, Tai Yao, Cheng‐Yan Xu, Tangling Gao, Shibo Xi, Ce Liang, Lingling Xu, Ping Xu, Bo Song
Abstract
Abstract To ensure sustainable hydrogen production by water electrolysis, robust, earth‐abundant, and high‐efficient electrocatalysts are required. Constructing a hybrid system could lead to further improvement in electrocatalytic activity. Interface engineering in composite catalysts is thus critical to determine the performance, and the phase‐junction interface should improve the catalytic activity. Here, we show that nickel diphosphide phase junction ( c ‐NiP 2 / m ‐NiP 2 ) is an effective electrocatalyst for hydrogen production in alkaline media. The overpotential (at 10 mA cm −2 ) for NiP 2 ‐650 ( c / m ) in alkaline media could be significantly reduced by 26 % and 96 % compared with c ‐NiP 2 and m ‐NiP 2 , respectively. The enhancement of catalytic activity should be attributed to the strong water dissociation ability and the rearrangement of electrons around the phase junction, which markedly improved the Volmer step and benefited the reduction process of adsorbed protons.