Unravelling critical role of metal cation engineering in boosting hydrogen evolution reaction activity of molybdenum diselenide

摘要

Two-dimensional(2D)transition-metal selenides,espe-cially MoSe_(2),is considered to be an excellent alternative electrocatalyst for the hydrogen evolution reaction(HER).However,it still features high overpotential in HER due to the low density of active sites,which limits its practical application.Herein,the hydrogen evolution reaction activity of MoSe_(2)is enhanced by the incorporation of metal-cation,tungsten,which succeeds in taking the place of Mo in the lattice of MoSe_(2),inducing the spacing expansion and bringing new flexural edges to serve as active sites.In addition,the incorporated metal also facil-itates electron transport from Mo active center toward W and Se atoms with auspicious hydrogen adsorption prop-erties.