Crystal facet-dependent CO2 cycloaddition to epoxides over ZnO catalysts

With regard to green chemistry and sustainable development, the fixation of CO2 into epoxides to form cyclic carbonates is an attractive and promising pathway for CO2 utilization. Metal oxides, renowned as promising eco-friendly catalysts for industrial production, are often undervalued in terms of their impact on the CO2 addition reaction. In this work, we successfully developed ZnO nanoplates with (002) surfaces and ZnO nanorods with (100) surfaces via morphology-oriented regulation to explore the effect of crystal faces on CO2 cycloaddition. The quantitative data obtained from electron paramagnetic resonance spectroscopy indicated that the concentration of oxygen vacancies on the ZnO nanoplate surfaces was more than twice that on the ZnO nanorod surfaces. Density functional theory calculations suggested that the (002) surfaces have lower adsorption energies for CO2 and epichlorohydrin than the (100) surfaces. As a result, the yield of cyclochloropropene carbonate on the ZnO nanoplates (64.7