Ga and Ti co-doped CeO2 nanorod catalysts with enhanced activity towards the synthesis of dimethyl carbonate from CO2 and methanol

Novel Ga and Ti co-doped CeO2 nanorod catalysts were synthesized using a one-pot hydrothermal process and characterized by XRD, TEM, FT-IR, Raman, N-2 adsorption-desorption, CO2-TPD, NH3-TPD, H-2-TPR and XPS techniques. Their catalytic properties were investigated in the synthesis of dimethyl carbonate (DMC) from methanol and CO2. Results showed that the addition of a small amount of Ti and Ga into CeO2 obviously enhanced the catalytic activity in the DMC formation from methanol and CO2. Among the series of Ga doped CeO2 catalysts, the Ce1Ga0.2Ti0.02 catalyst exhibited the best catalytic performance and the yield of DMC was as high as 24.6 mmol(DMC) g(cat)(-1) after 2 hours of reaction time, outperforming all reported catalysts without a dehydrating agent. The enhanced catalytic activity of the Ce1Ga0.2Ti0.02 catalyst is attributed to more surface oxygen vacancies and acid-base sites, favoring the activation of methanol and CO2 and further forming intermediate species and promoting DMC generation. This work provides two-element co-doped metal oxide catalysts for efficient conversion of CO2 to DMC.