Enhanced methyl nitrite carbonylation to dimethyl carbonate via fully exposed palladium cluster catalysts

Abstract

This work reports a fully exposed palladium cluster catalyst that exhibits superior activity and selectivity for methyl nitrite (MN) carbonylation compared to atomically dispersed Pd catalysts and Pd nanoparticles. Mechanistic studies reveal that the distinct geometric structure of the fully exposed palladium cluster enables surface-mediated Langmuir–Hinshelwood reactions, efficiently producing dimethyl carbonate (DMC) while minimizing dimethyl oxalate (DMO) formation. In contrast, atomically dispersed Pd catalysts rely on Eley–Rideal mechanisms, leading to lower activity, while the continuous surface sites of Pd NPs promote DMO formation. This work provides a foundation for the rational design of novel catalysts for industrial carbonylation processes.