Gallium-substituted self-pillared pentasil nanosheets combined with metal oxides for CO2 hydrogenation with enhanced selectivity of gasoline

Carbon dioxide hydrogenation to gasoline can effectively alleviate the energy crisis and benefit the global environment. Owing to its orthogonally connected nanosheet configuration, large pore volume, and appropriate thickness of single nanosheet, self-pillared pentasil (SPP) nanosheet zeolite is integrated with In₂O₃-ZrO₂ as a tandem catalyst for CO₂ hydrogenation to C₅₊ hydrocarbons. By substituting Al in the SPP framework with Ga, the acid strength of SPP is reduced, and acid density is increased, which favors the generation of C₅₊ hydrocarbons and enhances the cracking resistance of long-chain hydrocarbons. A maximum C₅₊ hydrocarbon selectivity of 82% was obtained on In₂O₃-ZrO₂/Ga-SPP (Si/Ga = 100), which shows no deactivation after 200 h reaction time. Furthermore, introducing Pd into the In₂O₃-ZrO₂ not only boosts CO₂ conversion to 11% but also suppresses methane selectivity to below 1%. This study offers valuable insights into the design of highly active CO₂-to-gasoline catalysts by leveraging the distinctive structure and acidity of zeolites within the tandem catalyst systems.