Influence of the defects on selective hydrogenation of cinnamaldehyde to cinnamyl alcohol over UiO-66 supported Pt catalysts

UiO-66 supported metal catalysts have shown high catalytic activity and selectivity to cinnamyl alcohol (COL) in the selective hydrogenation (SHYD) of cinnamaldehyde (CAL), but the roles of missing-linker defects (MLDs) in UiO-66 on the catalytic performance of the UiO-66 supported metal catalysts have less been reported. Here, UiO66 supports with the different amount of MLDs were used as the supports, and three series of UiO-66 supported Pt (Pt/U) catalysts were prepared by sol-impregnation, wet-impregnation as well as in-situ encapsulation methods, respectively. The influences of the MLDs in UiO-66 on the catalytic properties of the prepared Pt/U catalysts in the SHYD of CAL were investigated. The series of Pt/U-720 catalysts with the more MLDs showed higher CAL conversion and selectivity to COL than the corresponding Pt/U-F catalysts with fewer MLDs. The different preparing methods affect the location and dispersion of Pt species on UiO-66 supports and the metalsupport interaction, but the location of the supported Pt species on UiO-66 is the critical factor affecting the catalytic properties of Pt/U catalysts. The presence of the MLDs in UiO-66 is the key to preparing UiO-66 supported Pt catalysts with high SHYD performance.

Automated summary

UiO-66 supported Pt catalysts with different amounts of missing-linker defects (MLDs) were prepared and their catalytic properties were investigated. The Pt catalysts with more MLDs showed higher reaction conversion and selectivity. The preparation methods influenced the location and dispersion of Pt species on UiO-66 supports, and the location of supported Pt species on UiO-66 was the critical factor affecting catalytic performance.