Optimizing CO2 Hydrogenation to DME through Tailored Interfacial Interactions: Weakening Synergy in CuZnZr and Al-Modified SBA-15 Catalysts

The direct dimethyl ether (DME) synthesis reaction via CO2 hydrogenation typically requires a bifunctional catalyst that effectively combines a methanol synthesis catalyst with a methanol dehydration catalyst, but the effect of the relationship between the two catalysts on the catalytic performance has not been as well studied. In this study, we developed a CuZnZr/Al–S(10)-PG bifunctional catalyst physically mixed with Al-modified SBA-15 and the traditional CuZnZr catalyst for the hydrogenation of CO2 to DME. A pivotal discovery is that the modulation of interaction intensity between these two constituents significantly influences the electronic configuration of each component. Through X-ray photoelectron spectroscopy characterization and methanol dehydration experiments, it was confirmed that diminishing the synergistic interplay between CuZnZr and Al-modified SBA-15, which regulated the electronic structure of the Cu–Zn interface and enhanced the Cu–Zn interfacial interaction, played a crucial role in enhancing the catalyst’s performance in CO2 hydrogenation to DME. This finding contests established beliefs about the necessity of strong synergistic interactions in such systems and provides new insights for designing rational bifunctional catalysts.