An in situ growth strategy for core–shell Cua–Znb–Ox/ZSM-5@S-1 to boost dimethyl ether synthesis from CO2 hydrogenation

Abstract

The hydrogenation of CO₂ to dimethyl ether (DME) is often limited by low selectivity and poor catalyst stability. Herein, we report a core–shell zeolite-supported catalyst, denoted as Cu_a–Zn_b–O_x/ZSM-5@S-1, for efficient CO₂-to-DME conversion. Compared with single-zeolite supported catalysts, the core–shell catalyst exhibits markedly enhanced DME selectivity and long-term stability. Under 260 °C and 5.0 MPa, the optimized Cu₆–Zn₉–O_x/ZSM-5@S-1 achieves 22.3% CO₂ conversion and 85.9% DME selectivity while maintaining stable performance over 200 h. Characterization results reveal that the in situ grown S-1 shell forms an effective interface with the ZSM-5 core, which promotes metal redispersion and increases the density of active Cu⁺–ZnO_x sites.