Recent advances in Cu-based catalysts for CO2 hydrogenation to dimethyl ether

Copper-based catalysts are the most widely used systems for the direct catalytic hydrogenation of CO2 to dimethyl ether (DME). However, further improvements in catalytic selectivity, stability, and structural rationality are still needed to meet industrial demands. This review summarizes the recent progress in Cu-based catalysts for one-step CO2 hydrogenation to DME, with a focus on the evolution of active sites, reaction pathways, and the synergistic mechanism between hydrogenation and dehydration functions. Unlike existing reviews that focus mainly on catalytic performance, this work systematically analyzes the structural characteristics of Cu-based methanol synthesis components, the regulation of acidic dehydration sites, and the matching of bifunctional interfaces. The key challenges, including ambiguous active site identification, acid–base incompatibility, insufficient hydrothermal stability, and nonuniform evaluation criteria, are clarified. By highlighting the structure–performance relationships and unresolved mechanistic issues, this review aims to provide a reliable reference for the rational design and performance optimization of Cu-based catalysts for CO2 to DME conversion.