Reaction Mechanisms and Advanced Catalysts for Photothermal CO ₂ Methanation: A Comprehensive Review

ABSTRACT The excessive emission of CO 2 has triggered a range of environmental challenges, including ocean acidification and the greenhouse effect. To mitigate this issue, the catalytic conversion of CO 2 into value‐added chemicals has garnered significant attention. Among various approaches, photothermal catalytic CO 2 methanation stands out due to its mild reaction conditions and high product selectivity. In recent years, photothermal catalytic CO 2 methanation has made significant progress in the study of reaction mechanisms, regulation of catalyst structure and properties, and corresponding photothermal reactors. This review begins by examining the mechanism of CO 2 methanation, detailing the advantages of photothermal catalysis over thermal or photocatalysis. Then, the reaction pathways and key intermediates involved in CO 2 methanation were categorized and summarized, including the direct cleavage pathway, the reverse water‐gas shift (RWGS) pathway, and the formate pathway. Subsequently, the recent advances in photothermal catalytic CO 2 methanation catalysts, including oxide‐supported metal catalysts, carbide‐supported metal catalysts, and Metal–organic frameworks (MOFs) and their derivatives‐supported metal catalysts, were systematically summarized. Finally, the future and development prospects of photothermal CO 2 methanation are discussed. This review provides the latest reference for designing highly efficient photothermal CO 2 methanation catalysts for the future utilization of CO 2 resources.