Single-Atom-Alloy Catalysts for Enhanced Hydrogenation Reaction Process: Mechanism, Regulation Strategy, and Design Principle

In the fine chemical industry, selective hydrogenation reactions occupy a pivotal position and are effective ways to improve resource utilization. The development of highly efficient hydrogenation catalysts is important but still challenging. Single-atom-alloy catalysts (SAAs) combine the advantages of alloys and single-atom catalysts. The unique structures and synergistic effects can promote hydrogen dissociation and attenuate intermediate adsorption, which shows broad application prospects in fine chemical production. However, up to now, there have been very few systematic reviews on SAAs for enhanced hydrogenation reactions. Herein, we systematically summarized the existing research progress of SAAs in different selective hydrogenation reactions in the thermal-catalytic and electrocatalytic fields to provide a comprehensive reference for subsequent research. The mechanisms are deeply elucidated from the perspectives of substrate adsorption configurations, hydrogen activation, and hydrogen spillover effect. Then the corresponding structural regulation strategies of SAAs are clarified for improving the hydrogenation activity, selectivity, and stability, respectively. Furthermore, we propose the design principles of SAAs for enhancing the hydrogenation reaction process, which provide theoretical guidance for the targeted construction of efficient catalysts from the atomic scale. Finally, the prospect and challenge faced by SAAs in the selective hydrogenation field are proposed, so as to provide theoretical support for the development of catalysis science.