Rational design principles of single-atom catalysts for hydrogen production and hydrogenation

With the gradual transition from traditional energy to clean energy, hydrogen energy has gradually entered people's vision. Hydrogen production and hydrogenation are typical atom-economic reactions and play an irreplaceable role in global economic growth, but they encounter huge challenges. Single-atom catalysts (SACs) show the highest atomic utilization and uniform active sites, which have broad development prospects in hydrogen production and hydrogenation. Herein, we systematically review the research progress on SACs in hydrogen production and hydrogenation, reveal the origin of the high catalytic activity of SACs on the atomic scale, propose strategies for strengthening the reaction process, and summarize the rational design principles for SACs for hydrogen production and hydrogenation. Lastly, prospects are given to the present opportunities, challenges, and applications of SACs in hydrogen production and hydrogenation reactions. This review summarizes the research progress of single-atom catalysts (SACs) in hydrogen production and hydrogenation, and proposes the rational design principles of SACs for hydrogen production and hydrogenation firstly.