Light-Driven CO₂ Hydrogenation to Methanol: Photothermal Catalysis and Beyond

Photothermal CO₂ hydrogenation to methanol offers a promising strategy to overcome the thermodynamic-kinetic trade-off effect that limits conventional thermocatalysis. The rational design of effective catalysts relies on better understanding of the roles of light in driving or assisting the hydrogenation reaction. While high-energy photons generate the chemical potential (µ_e-h) of photogenerated charge carriers for non-thermal activation, low-energy photons are converted into localized heat to accelerate reaction kinetics. Building on this framework, we discuss the key light-driven mechanisms governing methanol synthesis, including carrier transport and interfacial injection, electronic reconstruction and valence-state regulation, photo-induced defect evolution, and dynamic surface restructuring. We further highlight how localized photothermal heating and spatial thermal management can be extended from the catalyst scale to the reactor scale through dual-temperature-zone engineering, enabling simultaneous optimization of kinetics and thermodynamics. Finally, key challenges and future directions are highlighted, providing perspectives for the development of practical solar-driven CO₂-to-methanol technologies.