Improving alkaline hydrogen evolution reaction kinetics on molybdenum carbide: Introducing Ru dopant.

• Simple strategy to prepare efficient electrocatalysts for alkaline HER. • Acceleration of HER kinetics on molybdenum carbide by introducing Ru components. • The synergistic effect between the introduced Ru components and molybdenum carbide. • Decrease of water dissociation energy barrier and weakening of adsorption of OH. Hydrogen evolution reaction (HER) under alkaline media plays a pivotal role in industrial electrocatalytic hydrogen production but even the platinum-based electrocatalysts suffer from high overpotential and low kinetics due to the high energy barrier of water dissociation. Here, by employing in-situ produced graphitic carbon nitride (g-C 3 N 4) as template to induce the formation of a lamellar structure, we reported evenly dispersed Ru-doped Mo 2 C nanoparticles on ultrathin nitrogen-doped carbon nanosheets (Ru-Mo 2 C/CN) as a highly efficient alkaline HER electrocatalyst. The optimal Ru-Mo 2 C/CN displays a remarkable activity with a low overpotential of only 34 mV to afford 10 mA cm−2 and good stability of more than 30 h, which is much better than that of commercial Pt/C and recently reported electrocatalysts in the landmark literatures. Density functional theory (DFT) calculations show that the introduced Ru dopant on Mo 2 C significantly reduce the water dissociation energy barrier of HER and inhibit the competitive adsorption between H* and OH* on the surrounding Mo sites. This work highlights a simple yet effective strategy for designing electrocatalysts with excellent performance of hydrogen evolution reaction in alkaline media. [ABSTRACT FROM AUTHOR]