Recent progress in the development of single-atom electrocatalysts for highly efficient hydrogen evolution reactions

To alleviate the energy crisis and environmental problems, efficient and stable electrocatalysts are desired for sustainable and scalable hydrogen production from water splitting. Rational design of single-atom catalysts (SACs) with remarkable performance for the hydrogen evolution reaction (HER) has become a topic of current interest due to the advantages of maximum atom utilization, unsaturated and adjustable coordination environment. Based on these, this review highlights the feasible synthetic and characterization methods of SACs at first, then, recent advances in effective SACs for the HER are summarized focusing on the structure-property relationships. Finally, the current issues and prospects are briefly addressed to provide some positive suggestions for the development of SACs for the HER.