Infrared and Thermo Co-Driven Catalysis for CO₂ Conversion to Valuable Chemicals.

Abstract

Conversion of CO₂ into high value chemicals presents a promising pathway for CO₂ mitigation and utilisation. The direct synthesis of dimethyl carbonate from CO₂ and methanol is one of such carbon-neutral pathways. However, thermal catalytic processes for direct dimethyl carbonate synthesis have reached a performance bottleneck at elevated temperatures. This work explores the synergy of photon and thermal energy to enhance the dimethyl carbonate production rate to 30 mmol/g/h, together with 100% selectivity, thanks to a defect-modified and noble-metal free cerium oxide catalyst. Fundamentally, it is found that the defects in cerium oxide can provide energy levels that enable IR light absorption and generate holes with a moderate oxidation potential, so avoiding the unfavorable overoxidation pathway and enhancing the production rate of dimethyl carbonate. The thermal energy has been proved to remarkably facilitate the relaxation of IR-induced charge carriers and to enhance the dimethyl carbonate formation process. This work introduces a strategy of IR photons and thermo co-driven catalysis and achieves a breakthrough in dimethyl carbonate formation.