Nitrogen anion-decorated cobalt tungsten disulfides solid solutions on the carbon nanofibers for water splitting

Abstract

A facile method to prepare nitrogen anion-decorated cobalt tungsten disulfides solid solutions, retaining ultra-thin WS2-like nanosheet structures (The N–CoxW1−xS2) anchored on carbon nanofibers (CNFs), is developed. The synergistic effect of the WS2 nanosheets provides a secure framework for stabilizing the amorphous Co–S clusters, CNFs substrate and nitrogen anion-decoration significantly enhances the inherent conductivity of the catalyst, resulting in a significantly promoted hydrogen evolution reaction activity and stable performance compared to pure Co9S8 nanoparticles or ultra-thin WS2 nanosheets. The N–CoxW1−xS2 electrode demonstrates the excellent electrocatalytic performance, with current density of 10 mA cm−2 at a low overpotential of 93 mV and Tafel slope of 85 mV dec−1, as well as the long-term stability in acid electrolyte. The present investigation may provide a feasible strategy for incorporating other heteroatoms into transitional metal disulfides materials to design catalysts with highly active and stable performance for water splitting.