Abstract
Driven by the global carbon neutrality goal, converting CO2 into value-added chemicals and fuels is a critical pathway for energy storage and carbon recycling. However, traditional photocatalysis suffers from severe charge recombination and low efficiency, while thermocatalysis is restricted by enormous energy consumption. Photothermal catalysis has emerged as a promising strategy by seamlessly integrating solar-driven charge excitation and localized thermal activation to overcome the kinetic and thermodynamic limitations of CO2 reduction. This review systematically summarizes the recent progress in the rational design of advanced materials for photothermal CO2 reduction. We begin by outlining the fundamental photothermal conversion mechanisms and categorizing the synergistic effects into three modes: photo-driven thermocatalysis, thermo-assisted photocatalysis, and synergistic photothermal catalysis. A quantitative evaluation framework for mechanistic decoupling is then established, integrating temperature-matched dark controls, spectrally resolved measurements, ultrafast in situ characterizations, and micro-nanoscale thermometry. We subsequently review state-of-the-art material design strategies, highlighting plasmonic metals, defect-engineered semiconductors, carbon-based nanocomposites, and tailored heterostructures, with critical comparisons of their respective advantages and operating conditions. Furthermore, we provide deep insights into the regulation of product selectivity, explicitly distinguishing the reverse water-gas shift reaction (RWGS), CO2 methanation, and photocatalytic reduction pathways, and analyzing the competitive pathways of C1 products and the kinetic bottlenecks of C2+ generation. Advanced microstructural optimization strategies, such as single-atom doping and facet engineering tailored to modulate the binding energies of key intermediates, are systematically discussed. We then examine energy efficiency analysis and advanced reactor engineering, emphasizing that genuine sustainability requires system-wide energy audits rather than reliance on apparent reaction rates. Finally, we outline the current challenges and future perspectives regarding long-term stability, thermal management, reactor design, and industrial-scale fabrication. This review aims to provide a clear roadmap for developing highly efficient and selective photothermal catalysts, thereby accelerating their practical applications in the green carbon economy.