Active Site-Mediated Photo-Thermo Catalysis for Methane Conversion

Transformation of methane, an increasingly sustainable feedstock rich in carbon and hydrogen, into various valuable chemicals is a crucial option contributing to achieving global carbon neutrality but chemically restricted to high energy of the C─H bond. Photo-thermo catalysis offers a promising approach to activate the C─H bond and thus facilitate methane conversion even under mild conditions upon an effective arrangement of the active site on the reaction interface of catalysts. Despite significant progress, the insufficient mechanistic understanding of how active sites function in the photo-thermo catalytic system remains a fundamental challenge. This review addresses the critical gap by systematically summarizing and categorizing various active sites of photo-thermo catalysts reported so far for activation of the C─H bond, and elucidating their specific roles in mediating different photo-thermo methane conversion reactions, including reforming, cracking selective oxidation, and C─C coupling. The aim is to provide in-depth yet currently absent insights into active site manipulation for the activation of C─H bonds in methane and even other hydrocarbons, followed by the design of tailored, highly efficient catalysts for photo-thermo conversion of hydrocarbons.