Boosting toluene deep oxidation by tuning metal-support interaction in MOF-derived Pd@ZrO2 catalysts: The role of interfacial interaction between Pd and ZrO2

The regulation of metal-support interaction is one of the productive strategies to enhance volatile organic compounds (VOCs) deep degradation. Herein, Pd@ZrO2 catalysts were synthesized via using in-situ growth Zr-based metal organic framework (MOF) Pd@UiO-66 as the precursor to boost toluene deep degradation. Compared with Pd@ZrO2-Zr(OH)4 synthesized by using Zr(OH)4 as the precursor, MOF-derived Pd@ZrO2 catalysts with different calcination time exhibited more superior catalytic performance, water-resistance and stability. Characterizations results indicated the occurrence of interfacial interaction in MOF-derived Pd@ZrO2 induced the better reducibility at low-temperature and the generation of oxygen vacancies, enhanced Oads species content, weakened Zr-O bond strength, improved the mobility of Olat species, which caused its better toluene degradation performance. Simultaneously, in-situ diffuse reflectance infrared Fourier transform spectroscopy results clarified that the interfacial interaction heightened the adsorption and activation ability for gaseous oxygen to form reactive oxygen species and replenish consumed Olat species, promoted toluene ring-opening reaction, reduced benzoate acid species cumulation, expedited the fast deeply degradation of toluene to CO2 and H2O. This work may provide a new perspective on MOF-derived catalysts with better performance for VOCs degradation deeply by tuning interfacial interaction.