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

A facile method to prepare nitrogen anion-decorated cobalt tungsten disulfides solid solutions, retaining ultra-thin WS₂-like nanosheet structures (The N-Co _x W_1-x S₂) 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-Co _x W_1-x S₂ 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.