Sulfur-Doped Rhenium Selenide Vertical Nanosheets: A High-Performance Electrocatalyst for Hydrogen Evolution

Developing highly efficient electrocatalysts for hydrogen generation from water has been a crucial option for future energy conversion and storage. Rhenium dichalcogenides (ReX2, X=S or Se) have attracted tremendous research interests due to their unique distorted-1T phase and anisotropic electronic structure. So far, there is no report about S doped ReSe2 electrocatalyst. In this work, we present a three-dimensional nanosheets electrocatalyst derived from sulfur-doped rhenium selenide (ReSe2(1-x)S2x) grown on carbon fiber paper (CFP) for water splitting. It is noting that the catalytic activity could be significantly fine-tuned by controlling quantity of sulfur dopant. ReSe1.78S0.22/CFP cathode exhibits the best performance with a Tafel slope of 84 mVdec(-1), an overpotential of 123 mV to drive the current density of 10 mA cm(-2) as well as a long-term stability of 30 h. The X-ray photoelectron spectroscopy and density functional theory calculations confirm that sulfur-doped structure, especially the dangling sulfur atoms adsorbed on the surface Se atom kars, achieves a more thermoneutral hydrogen adsorption energy, conducing an optimized catalytic activity of the basal plane. This study demonstrates that S doped ReSe2 could be a promising candidate electrocatalyst for hydrogen evolution.