Efficient Role of Nanosheet-Like PrO Induced Surface-Interface Synergistic Structures over Cu-Based Catalysts for Enhanced Methanol Production from CO Hydrogenation.

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 PrO nanosheets for high-efficiency CO 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 Cu sites and the coexistence of abundant defective Pr-V-Pr structures (V: 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-PrO interfaces over the catalyst remarkably promoted the adsorption of CO and CO intermediate, thus boosting the CO hydrogenation simultaneously 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 g·g·h 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 CO hydrogenation to produce methanol and a deep understanding of the promotional roles of synergy between surface-interface active sites in the CO hydrogenation.