Regulating Catalytic Performance for CO Hydrogenation to Higher Oxygenates through Strong Metal–Support Interaction

Optimizing the CO hydrogenation to higher oxygenates (C2+-Oxy) is both an intriguing opportunity and significant challenges. The strong metal–support interaction (SMSI) provides a promising avenue to regulate catalytic performance of CO hydrogenation, as it facilitates the encapsulation of nanoparticles and the modulation of active sites. In this study, we proved that Rh/MnO2 exhibited SMSI subsequent to H2 reduction. The coverage of MnOx suboxides on the surface of Rh particles was regulated by the reduction temperature, which in turn affected the quantity of consecutive Rh sites and the Rh+/Rh0 ratio. This modulation contributed to an improvement in both the catalytic activity and selectivity for C2+-Oxy. Based on synchrotron-based vacuum ultraviolet photoionization mass spectrometry results, the presence of ketene (CH2CO) indicated that the initial carbon–carbon coupling might occur between the adsorbed *CH2 and *CO. Subsequently, two different C2 oxygenated intermediates were constructed, and the dominant one was also regulated by the MnOx coating, thereby adjusting the ratio of aldehyde and alcohol products. This study expands upon the catalyst system of SMSI and offers a significant contribution to understanding of the reaction mechanism involved in the C2+-Oxy synthesis.