Ru monolayer island doped MoS2 catalysts for efficient hydrogen evolution reaction

Ru monolayer islands-doped MoS 2 catalysts were prepared by the high-gravity technology, and the catalyst exhibits ultralow overpotential of 17 mV at 10 mA cm -2 in alkaline medium, which is attributed to its high-density active sites. • Ru monolayer islands-doped MoS 2 catalysts (MIs-MoS 2 ) have been prepared by the high-gravity technology. • MIs-MoS 2 possesses high-density active sites for boosting the HER activity. • MIs-MoS 2 exhibits ultralow overpotential of 17 mV at 10 mA cm -2 in alkaline medium. • DFT calculations reveal that Ru monolayer doping can optimize the electronic structure to boost HER performance. Developing highly-efficient hydrogen evolution reaction (HER) catalysts is significantly important for hydrogen generation by water splitting. In this work, Ru monolayer islands (MIs)-doped MoS 2 catalysts are synthesized controllably by high-gravity technology. Ru MIs are successfully anchored on the MoS 2 nanosheets via the coordination of Ru and S species in the MoS 2 matrix to form monolayer island structure, which not only provides high-density active centers for boosting the HER activity, but also exhibits the maximum atomic utilization. The prepared Ru MIs-doped MoS 2 catalysts exhibit a remarkably low overpotential of 17 mV at the current density of 10 mA cm -2 (η 10 ) in alkaline conditions. Density functional theory (DFT) results reveal that multi-Ru monolayer doping can efficiently tailor the electronic structure and improve the adsorption of hydrogen on MoS 2 , and thereby boost the catalytic activity of HER. This work provides a Ru MIs doping approach to enhance the density of active sites of electrocatalysts, which would overcome the bottleneck of low active site density of single-atom catalysts to design high-efficient electrocatalysts with maximum atomic utilization.