关键词: InZrO_x/Cu反相结构, 核壳催化剂, Ga-MFI分子筛, 催化CO₂加氢, 芳烃选择性

Abstract: Constructing tandem catalysts with efficient coupling between metal-oxide hydrogenation sites and zeolite aromatization sites is crucial for improving CO2 hydrogenation to aromatics. Herein, a core-shell catalyst consisting of porous InZrOx/Cu microspheres as the core and a Ga-MFI zeolite shell with preferential radial alignment of the b-axis straight channels was prepared via a coating-assisted dry-gel conversion method. The results showed that the introduction of In promoted Cu-In interactions and enhanced the formation of defect sites associated with In-Zr oxide species, thereby improving CO2 adsorption and activation, as well as facilitating the formation of methanol-related intermediates such as HCOO* and H2CO*. The outer Ga-MFI shell shortened the diffusion path of oxygenate intermediates, and framework Ga-derived Bronsted acid sites and extra-framework GaOx/GaO+ species cooperatively promoted dehydration, oligomerization, cyclization, and dehydroaromatization. Benefiting from these structural features, the core-shell catalyst achieved a CO2 conversion of 32.4% and an aromatic selectivity of 45.0% at 320 °C and 3 MPa, and showed no obvious deactivation during a 100 h stability test. This work provides a useful strategy for designing spatially confined tandem catalysts for CO2 hydrogenation to aromatics.

Key words: Inverse InZrO_x/Cu structure, Core-shell catalyst, Ga-MFI zeolite, CO₂ hydrogenation, Aromatics selectivity