Single atom Ru doping 2H-MoS2 as highly efficient hydrogen evolution reaction electrocatalyst in a wide pH range

Abstract It’s a huge challenge to develop a hydrogen evolution reaction (HER) catalyst with a wide pH range. Herein, single atom ruthenium-doped molybdenum disulfide with high 2H phase content (Ru@2H-MoS2) catalysts are synthesized by a two-step hydrothermal method, they are named as Ru0.05@2H-MoS2, Ru0.10@2H-MoS2 and Ru0.12@2H-MoS2 based on the amount of Ru (mmol) added to 2H-MoS2. The results indicate that single atom Ru substituting for molybdenum atom leads to more active centers and some vacancies, thus improving the property of 2H-MoS2 for HER. Among them, Ru0.10@2H-MoS2 shows the lowest HER overpotentials of 137, 51 and 168 mV at 10 mA cm-2 in 1.0 M PBS, 1.0 M KOH and 0.5 M H2SO4, respectively. The density functional theory (DFT) further indicates that the Ru@2H-MoS2 has a lower Gibbs free energy of H-adsorption (ΔGH*). Therefore, this study offers an effective way to reasonably design and synthesize efficient MoS2-based catalysts in a wide pH range.