Band structure engineering of W replacement in ReSe₂ nanosheets for enhancing hydrogen evolution

Layered transition metal dichalcogenide rhenium selenide (ReSe₂) has attracted great attention as an electrocatalyst for the hydrogen evolution reaction (HER) due to its excellent stability and sufficient active sites. However, ReSe₂ has intrinsically poor conductivity, which leads to the insufficient utilization of electrocatalytic active sites. Herein, we designed the regulation of the electronic band structure by W replacement in ReSe₂ nanosheets to greatly improve the conductivity. The Re_0.7W_0.3Se₂ exhibits an overpotential of 141 mV at 10 mA cm^-2 and a Tafel slope of 65.3 mV dec^-1, superior to that of the original ReSe₂ and WSe₂. This work aims to provide a feasible strategy to promote the HER activity of ReSe₂.