Enhance CO2 hydrogenation to methanol over Cu/ZnO foam monolithic catalysts: the role of excitation of active copper and metal-oxide interface effects

The development of efficient monolithic catalysts for CO 2 hydrogenation to methanol holds great significance in addressing the industrial application of Cu-based catalysts. In this study, a series of monolithic catalysts by coupling MOFs-derived oxides with Cu(OH) 2 transition layers loaded on copper foam (CF) are successfully prepared, in which the content of active Cu can be facilely controlled by tuning Cu(OH) 2 load. And various characterization results prove that the metal-oxide interface effect is successfully applied in monolithic catalysts. This strategy offers the unique advantage of constructing the rich metal-oxide interface over monolithic catalysts; thus, significantly enhances the methanol synthesis activity. Furthermore, utilizing this phenomenon, many yZC x CF (x = 1.25, 2.5) catalysts are synthesized by adjusting the amounts of MOFs-derived oxides, revealing an ideal Cu/Zn ratio may optimize the metal-oxide interface (Cu-ZnO interface) on the catalysts. Notably, the 4ZC 2.5 CF catalyst demonstrates the highest methanol space–time yield (STY) of 183 g·kg cat -1 ·h −1 and 150 h of stability. The “Cu(OH) 2 transition layer control interface” strategy proposed in this study provides the feasibility and key parameters in the large-scale preparation of monolithic catalysts.