Facile and Scalable Mechanochemical Synthesis of Defective MoS2 with Ru Single Atoms Toward High-Current-Density Hydrogen Evolution

Designing a facile strategy to prepare catalysts with highly active sites are challenging for large-scale implementation of electrochemical hydrogen production. Herein, a straightforward and eco-friendly method by high-energy mechanochemical ball milling for mass production of atomic Ru dispersive in defective MoS2 catalysts (Ru-1@D-MoS2) is developed. It is found that single atomic Ru doping induces the generation of S vacancies, which can break the electronic neutrality around Ru atoms, leading to an asymmetrical distribution of electrons. It is also demonstrated that the Ru-1@D-MoS2 exhibits superb alkaline hydrogen evolution enhancement, possibly attributing to this electronic asymmetry. The overpotential required to deliver a current density of 10 mA cm(-2) is as low as 107 mV, which is much lower than that of commercial MoS2 (C-MoS2, 364 mV). Further density functional theory (DFT) calculations also support that the vacancy-coupled single Ru enables much higher electronic distribution asymmetry degree, which could regulate the adsorption energy of intermediates, favoring the water dissociation and the adsorption/desorption of H*. Besides, the long-term stability test under 500 mA cm(-2) further confirms the robust performance of Ru-1@D-MoS2. Our strategy provides a promising and practical way towards large-scale preparation of advanced HER catalysts for commercial applications.

Automated summary

A facile and eco-friendly method of high-energy mechanochemical ball milling is developed to prepare Ru-1@D-MoS2 catalysts, which exhibit superb alkaline hydrogen evolution enhancement. The single atomic Ru doping induces the generation of S vacancies, leading to an asymmetrical distribution of electrons, which contributes to the excellent performance of Ru-1@D-MoS2.