Defective MZrOx-supported Pt catalysts for catalytic oxidation of glycerol: tailoring oxygen vacancy over the support

Abstract

In heterogeneous catalytic reactions, the optimization of surface synergy by adjusting noble metal–support interaction remains a significant challenge. In glycerol oxidation reaction (GOR), introducing oxygen vacancies (O_v) through defect engineering to promote electron transfer, and thus, improve catalytic activity is one of the effective methods. In this work, a series of MZrO_x solid solution supports (M = Cu, Mn, Fe, Co, Ni, Zn) were prepared by the co-precipitation method. Then Pt nanoparticles (Pt NPs) were loaded onto the MZrO_x support by colloidal-deposition method. The supported Pt/MZrO_x catalysts were evaluated for GOR under base-free conditions. The results showed that the Pt/CuZrO_x catalyst has optimal catalytic performance. The conversion rate of glycerol and the selectivity of glyceric acid reached 90.5% and 71.4%, respectively. Multi-characterization techniques were employed to analyze the physicochemical properties of the catalysts. It was revealed that the incorporation of a certain amount of M-doping could optimize the abundance of oxygen vacancies, Pt^δ+ species, redox properties, and surface acid-basic properties of the supported catalysts, while promoting the formation of strong metal–support interactions (SMSIs), thereby synergistically optimizing the performance of catalysts. These results may offer improved insights and methodologies for the rational design of Pt-based catalysts for GOR under base-free conditions.