Near-Infrared-Responsive Catalysts for Gas-Solid Phase Photocatalytic CO2 Reduction: Design Strategies, Performance, Future Perspectives.

The escalating atmospheric carbon dioxide (CO2) concentration and depletion of fossil fuels have spurred intensive research into sustainable CO2 conversion technologies. The photocatalytic CO2 reduction reaction (CO2RR) in gas-solid phase systems offers distinct advantages over liquid-phase counterparts, including enhanced mass transfer, simplified product separation and reduced side reactions. Notably, near-infrared (NIR) light constitutes approximately 50% of the solar spectrum; however, traditional photocatalysts rarely utilize this low-energy region, thereby limiting overall solar-to-chemical conversion efficiency. This review systematically summarizes the rationale, design strategies and catalytic performance of NIR-responsive photocatalysts for gas-solid phase CO2RR. Key approaches include the engineering of metallic/narrow-bandgap conductors, the introduction of defects/intermediate bands, the construction of plasmonic heterojunctions, atomic-level doping, the integration of single-atom active sites and the development of metal-free photothermal systems. These strategies address core challenges such as extending spectral response, enhancing charge separation and optimizing CO2 activation. Representative catalysts exhibit efficient NIR-driven CO2 reduction to value-added products (e.g., carbon monoxide, methane, methanol) with high selectivity and stability. This review provides critical insights into unlocking full-spectrum solar energy utilization and advancing practical CO2RR technologies for carbon neutrality.