Local In-O-Pd Lewis acid-base pair boosting CO₂ selective hydrogenation to methanol

CO2 hydrogenation into valuable chemicals is industrially essential but very challenging since CO2 is chemically inert and the selectivity is difficult to control. Here, we design and construct In2O3 supported Pd single atoms (Pd-1/In2O3 SAC) to boost the methanol yield (254.8 g(methanol).g(Pd)(-1).h(-1)) and selectivity (99.4 %) via the Lewis acid-base pair, which activates the CO2 and forms the intermediate species of formate (HCOO*). The comprehensive experimental and theoretical results confirm that the local Lewis acid-base pair is composed of the isolated Pd atom coupling with the adjacent O and In atoms. The space-time yield (STY) of methanol over Pd-1/In2O3 SAC is around 1.7 times higher than the best reported catalysts under comparable conditions. The strategy of constructing local Lewis acid-base pairs with single-atom site and metal oxides reported in this work opens new avenues to develop highly selective catalysts for CO2 utilization.