Efficient Role of Nanosheet-Like Pr<sub>2</sub>O<sub>3</sub> Induced Surface-Interface Synergistic Structures over Cu-Based Catalysts for Enhanced Methanol Production from CO<sub>2</sub> Hydrogenation
Guangcheng Zhang, Mengran Liu, Guoli Fan, Lirong Zheng, Feng Li
Abstract
In a complex heterogeneous metal-catalyzed reaction process, unique cooperative effects between metal sites and surface-interface active sites, as well as favorable synergy between surface-interface active sites, can play crucial roles in improving their catalytic performances. In this work, a ZnO-modified Cu-based catalyst over defect-rich Pr2O3 nanosheets for high-efficiency CO2 hydrogenation to produce methanol was successfully constructed. It was demonstrated that an as-fabricated nanosheet-like Cu-based catalyst presented several structural advantages including the formation of highly dispersive Cu0 sites and the coexistence of abundant defective Pr3+–Vo–Pr3+ structures (Vo: oxygen vacancy) and interfacial Cu–O–Pr sites. Combining structural characterization and catalytic reaction results with density functional theory calculations, it was clearly unveiled that the synergy between surface defective structures and Cu–Pr2O3 interfaces over the catalyst remarkably promoted the adsorption of CO2 and CO intermediate, thus boosting the CO2 hydrogenation simultaneously via both the formate intermediate pathway and the intense reverse water–gas shift reaction-derived CO hydrogenation pathway, along with a high space-time yield of methanol of 0.395 gMeOH·gcat–1·h–1 under mild reaction conditions (260 °C and 3.0 MPa). The study provides a new strategy to construct high-performance Cu-based catalysts for high-efficiency CO2 hydrogenation to produce methanol and a deep understanding of the promotional roles of synergy between surface-interface active sites in the CO2 hydrogenation.