Boosting the catalytic behavior and stability of a gold catalyst with structure regulated by ceria

In this work, a series of colloidal gold nanoparticles with controllable sizes and CeO2 promotion were anchored on carbon nanotubes (CNT) for the aerobic oxidation of benzyl alcohol.

High Efficient and Stable Thiol-Modified Dendritic Mesoporous Silica Nanospheres Supported Gold catalysts for Gas-phase Selective Oxidation of Benzyl Alcohol with Ultra-Long Lifetime

Thiol-modified dendritic mesoporous silica nanospheres (DMSNs) supported Au catalyst were facilely prepared and used in gas-phase selective oxidation of benzyl alcohol with O2 as the oxidant. The Au/DMSNs-4.4%SH catalyst with low loading of Au (~2%) and proper amount of thiol ligand (~4.4%) achieved high conversion of benzyl alcohol (Conv. 91%) and selectivity for benzaldehyde (Sel. 98%) and unprecedented lifetime up to 820 h at 250 °C. The dramatically increased lifetime is the consequence of the strong stabilization of active gold nanoparticles by thiol ligand and the effective mass diffusion of DMSNs with opened three-dimensional mesoporous networks.

A Novel Pd-P Nano-Alloy Supported on Functionalized Silica for Catalytic Aerobic Oxidation of Benzyl Alcohol

Catalytic aerobic oxidation of benzyl alcohol (BnOH) to benzaldehyde (PhCHO) over supported noble metal catalysts has grabbed the attention of researchers due to the critical role of PhCHO in numerous industrial syntheses. In the present study, a novel catalyst, Pd-P alloy supported on aminopropyl-functionalized mesoporous silica (NH2-SiO2), was prepared through in situ reduction and characterized by BET-BJH analysis, SEM, TEM, XRD, FTIR, TG-DTA, and XPS. Chemical properties and catalytic performance of Pd-P/NH2-SiO2 were compared with those of Pd0 nanoparticles (NPs) deposited on the same support. Over Pd-P/NH2-SiO2, the BnOH conversion to PhCHO was much higher than over Pd0/NH2-SiO2, and significantly influenced by the nature of solvent, reaching 57% in toluene at 111 °C, with 63% selectivity. Using pure oxygen as an oxidant in the same conditions, the BnOH conversion increased up to 78%, with 66% selectivity. The role of phosphorous in improving the activity may consist of the strong interaction with Pd that favours metal dispersion and lowers Pd electron density.