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 spec-troscopy 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.

Automated summary

The regulation of metal-support interaction is an effective strategy to enhance the deep degradation of volatile organic compounds (VOCs). In this study, Pd@ZrO2 catalysts were synthesized using a Zr-based metal organic framework (MOF) as the precursor, and they exhibited superior catalytic performance, water-resistance, and stability compared to catalysts synthesized using Zr(OH)4 precursor. Characterization results revealed that the interfacial interaction in the MOF-derived Pd@ZrO2 catalysts improved reducibility, increased oxygen vacancies and adsorption of gaseous oxygen, leading to better toluene degradation performance. This work provides a new perspective on MOF-derived catalysts for the deep degradation of VOCs by tuning interfacial interaction.