Light-driven reforming of methane through photothermal catalysis

Photothermal catalytic methane reforming (PTCMR) demonstrates a transformative strategy for harnessing full-spectrum sunlight to produce clean solar fuels. Despite extensive efforts related to catalyst development, the pathways and mechanistic complexities arising from photothermal coupling remain underexplored. As such, this Review elucidates the interplay between photochemical and photothermal processes that govern PTCMR, illustrating how photogenerated carriers and localized heating cooperatively or competitively influence reactant adsorption, activation, transformation and active-site evolution. Particular attention is devoted to highlighting the gradient fields (such as, temperature, potential and concentration) within the reactor microenvironment inherent to PTCMR, which exert kinetic control while complicating the quantitative differentiation of intertwined photochemical and photothermal contributions. We examine these challenges and propose novel strategies, integrating catalyst design, reactor engineering and system-coupling to regulate charge-heat interactions and mitigate non-uniform energy effects. Finally, we outline future directions for mechanistic studies and the scalable implementation of next-generation solar-driven methane valorization technologies.