Tunable Oxygen Vacancy Clusters Enhanced Catalytic Activity of CeO2 Nanorods on CO2 Cycloaddition

AbstractConstructing heterogeneous halogen‐free catalysts featuring efficiently activated CO2 and epoxides for the synthesis of cyclic carbonates via an atom‐economical route is significant but remains a big challenge. In this work, we develop an atmosphere‐assisted strategy for preparing mesoporous CeO2 nanorods with tunable oxygen vacancy cluster concentrations, which boosts the performance of CO2 cycloaddition. Pair distribution function (PDF) analysis elucidates that oxygen vacancy clusters regulate the dynamic equilibrium of the multiscale structure of CeO2 via a synergistic “compression‐expansion” mechanism. Furthermore, the high concentrations of oxygen vacancy clusters form abundant frustrated Lewis pairs (FLP) sites, which remarkably promote the adsorption and activation of CO2 with epoxides. Thus, the performance of CO2 cycloaddition was substantially intensified. A 95% yield of cyclic carbonate was obtained when the reaction was conducted with RNR‐CeO2‐H2 at 110 °C. Moreover, the kinetic properties and the catalytic mechanism of CO2 cycloaddition on FLP sites in RNR‐CeO2‐H2 were investigated based on the in situ DRIFTS and DFT calculations. Thus, this work provides new insights into the design of high‐performance catalysts with tunable FLP sites for the efficient activation and conversion of CO2 into value‐added chemicals by modulating oxygen vacancy cluster concentrations.