Boosting CO2 hydrogenation to methanol via ternary Cu-Zn-Zr catalyst: The critical role of interface confinement effect (ICE)

Abstract

Tuning metal-support interactions in catalysts represents a promising strategy for optimizing the catalytic activity of CO2 hydrogenation. Here, CuZnZr ternary catalysts with varied interfacial structures were fabricated by altering the metal loading sequence to elucidate the interactions between different counterparts. Compared to reference catalysts with different interfaces (Cu-ZnZr, Zn-CuZr and Zr-CuZn), CuZnZr synthesized via the coprecipitation method (CZZ) displays the highest catalytic performance, achieving a CO2 conversion rate of 13.3 %, methanol selectivity of 71.3 %, and a STY of 12.2 mmolMeOH·gcat-1·h-1 under optimal conditions. Extensive characterization results indicate that this exceptional activity originates from the synergistic optimization of both structure and reaction mechanism, driven by the interface confinement effect (ICE) enabled by abundant interfacial sites. Specifically, the surface of CZZ shows high density of highly dispersed Cu0 nanoparticles and rich oxygen vacancy sites, which is beneficial to the activation of H2 and the adsorption of CO2. In-situ DRIFTS further revealed that, compared to reference catalysts, CO2 hydrogenation on CZZ follows both the HCOO* and COOH* pathways, leading to a substantial improvement in overall catalytic activity. In summary, this study provides a deeper understanding of the ICE and their impacts on catalytic performance, offering a valuable theoretical insight for the design of high-performance catalysts in future research.