Catalytic Conversion of CO2 to Methanol: Advances in Catalyst Design and Plasma-Assisted Technology

The hydrogenation of CO2 to methanol is a crucial route for achieving carbon recycling. Among the extensively studied catalysts, copper-based catalysts suffer from insufficient activity and stability, while noble metal catalysts are limited by prohibitively high cost. In contrast, metal–organic framework (MOF) materials demonstrate unique advantages due to their designable architectures and high dispersion. Conventional thermal catalysis relies on high temperature and pressure; photocatalysis suffers from low efficiency; and electrocatalysis shows poor selectivity. These limitations motivate the exploration of new catalytic approaches. Plasma catalysis, particularly dielectric barrier discharge (DBD) technology, can efficiently activate CO2 via high-energy electrons and reactive species at ambient temperature and pressure, and generate a synergistic effect with catalysts, significantly enhancing methanol production efficiency and selectivity. Studies have shown that plasma–catalyst synergistic systems, such as those employing Cu/γ-Al2O3 or Pt/In2O3, exhibit superior performance to individual processes under mild conditions. Future research should focus on elucidating the plasma–catalyst interface mechanism, optimizing reactor design, and developing compatible, high-efficiency catalysts to establish a novel pathway for CO2 conversion with low energy consumption and high efficiency.