Boosting CO2 hydrogenation to methanol via non-thermal plasma over Cu-CeZrOx catalyst

CO 2 hydrogenation to methanol is severely constrained by thermodynamic equilibrium limitations and rapid catalyst deactivation at elevated temperatures. To address these challenges, a novel strategy integrating dielectric barrier discharge (DBD) non-thermal plasma (NTP) with Cu-Ce-Zr solid solution catalysts was adopted for low-temperature methanol synthesis. A series of Cu-Ce 1-x Zr x O 2 (x = 0.2–0.8) catalysts with varying Zr/Ce ratios were synthesized to systematically investigate the regulatory mechanism of lattice defects on the plasma-catalytic performance and the potential synergy between the plasma and catalyst. Characterization results revealed that an optimal Zr content (x = 0.6) maximized the surface oxygen vacancy concentration, generating abundant Ce 3+ -O v -Zr 4+ sites and stabilizing highly dispersed active Cu species. At near-ambient temperature and atmospheric pressure with optimal discharge parameters (30 kV, 9 kHz), the plasma-assisted Cu-Ce 0.4 Zr 0.6 O 2 system achieved CO 2 conversion of 20.5 % with methanol selectivity of 50.6 %, corresponding to methanol space–time yield of 148.4 mg·g cat -1 ·h −1 . A strong synergy was observed between the plasma and the Cu-Ce 0.4 Zr 0.6 O 2 catalyst. The plasma efficiently activated gas-phase molecules, while the catalyst regulated the hydrogenation pathway to promote CH 3 OH formation and suppress side reactions. Compared to the plasma-alone mode, the energy consumption for methanol production was reduced by 81.5 %, and the system exhibited excellent stability over 24 h of continuous operation. This work provides insights into the rational design of catalysts for application in NTP-catalytic systems.