Regulating CO2 Hydrogenation Pathways with High-Entropy Catalysts

Abstract The catalytic hydrogenation of CO2 offers a promising route for carbon utilization but remains fundamentally constrained by the inertness of CO2 and the complexity of competing reaction pathways. High-entropy alloys and high-entropy oxides, composed of five or more principal elements stabilized by configurational entropy, have recently emerged as a transformative platform for addressing these challenges. This Review provides a critical and focused overview of entropy-driven catalyst design for CO2 hydrogenation, including CO formation via reverse water−gas shift, methanation, methanol synthesis, C2+ olefin production, and formic acid generation. Emphasis is placed on synthetic strategies enabling atomic-level mixing, mechanistic insights into multi-site cooperation, dynamic exsolution-dissolution behavior, and the roles of lattice distortion, oxygen vacancies, and strong metal−support interactions in regulating activity and selectivity. By integrating experimental advances with emerging structure−function relationships, this work delineates the opportunities, limitations, and future directions of high-entropy catalysts as adaptive systems for efficient and durable CO2 valorization.