Ga-induced construction of LaGaOx/Cu interfacial sites for CO2 hydrogenation to methanol over La2O2CO3-supported catalysts

Ga doping constructs novel LaGaO x /Cu interfacial structure. • LaGaO x /Cu interfaces stabilize Cu + species by electronic metal-support interaction (EMSI) for methanol synthesis. • Ga incorporation promotes adsorption of H 2 , CO 2 and CO. • LOC/Cu:5Ga delivers a methanol space-time yield of 306.7 g kg cat −1  h −1 . • Ga-induced interfaces shift the reaction from a single to a dual-path mechanism. Developing efficient copper-based catalysts for CO 2 hydrogenation to methanol remains a key challenge in catalytic CO 2 utilization. Irreducible rare-earth oxides offer outstanding thermal stability and structural robustness, yet their limited activity and selectivity restrict methanol productivity. Herein, we propose a promoter-induced interfacial engineering strategy to activate La 2 O 2 CO 3 (LOC)-supported Cu catalysts by incorporating Ga as a heteroatom promoter. A series of Ga-doped LOC/Cu catalysts (denoted as Cu:xGa) were synthesized via a two-step co-precipitation method, exhibiting a pronounced dependence of catalytic performance on Ga loading. The optimized Cu:5Ga catalyst achieved a CO 2 conversion of 9.2% and a methanol space-time yield of 306.7 g kg cat −1  h −1 (3 MPa, 260 °C), corresponding to a 9.8-fold enhancement relative to undoped Cu. Comprehensive structural and spectroscopic characterizations reveal that Ga doping induces the formation of highly dispersed LaGaO x /Cu interfacial sites. The enhanced electronic metal-support interaction (EMSI) at these interfaces optimizes the electronic structure of Cu sites, facilitating reactant activation and further boosting methanol synthesis. These interfaces stabilize interfacial Cu + species, facilitating the dissociation and adsorption of reactants, and fundamentally modify the reaction pathway from a single formate route to a dual mechanism involving both the formate pathway and the RWGS–CO hydrogenation pathway. This work demonstrates an effective strategy to activate irreducible rare-earth oxide–supported Cu catalysts and provides mechanistic guidance for the rational design of efficient and stable catalysts for CO 2 hydrogenation to methanol. Efficient synthesis of methanol via a promoter (Ga)-induced interfacial engineering strategy to activate La 2 O 2 CO 3 (LOC)-supported Cu catalysts, corresponding to a 9.8-fold enhancement relative to undoped LOC/Cu catalyst. Download: Download high-res image (133KB) Download: Download full-size image