Biosynthesized Bimetallic Au–Pd Nanoparticles Supported on TiO₂ for Solvent-Free Oxidation of Benzyl Alcohol

Abstract

A green bioreductive approach with Cacumen Platycladi (CP) extract was adopted to fabricate bimetallic Au− Pd/TiO 2 catalysts for solvent-free oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) with molar oxygen at atmospheric pressure. The Au−Pd nanoparticles (NPs) before being immobilized onto TiO 2 were determined by transmission electron microscopy. And, the catalysts were further analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetric analysis, etc. Effects of Au/Pd molar ratio, preparation conditions, and reaction conditions on the catalytic activity of Au− Pd/TiO 2 were investigated. And, the Au−Pd/TiO 2 catalyst without calcination that was prepared at 90 °C from the Au−Pd NPs with Au/Pd molar ratio of 2:1 exhibited excellent catalytic performance. With the catalyst, BzOH conversion of 74.2% and selectivity to BzH 95.8% were attained at the reaction temperature of 90 °C with an oxygen flow rate of 90 mL/min. Meanwhile, the recycling tests showed that, after seven recycles, the catalyst still remained with high conversion and selectivity. Therefore, the catalyst had excellent durability and reusability and good prospects for industrial application.

Design and synthesis of W-containing mesoporous material with excellent catalytic activity for the oxidation of 4,6-DMDBT in fuels

“…The calcination temperature had great effect on the catalytic activity of the catalysts [62,63]. As shown in Fig.…”

Nanoparticle Synthesis by Biogenic Approach

“…Carbohydrates and organic acids, present in C. paradisi were believed to be responsible for the formation of nanoparticles [ 89 ]. Also, Hang et al reported bimetallic Au-Pd/TiO 2 catalysts for solvent-free oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) with Cacumen platycladi ( CP ) extract [ 90 ]. With high BzOH conversion (~78 %) and selectivity (~96 %), recycling tests showed that even after seven recycles, the catalyst still remained suggesting excellent durability and reusability leading towards industrial application [ 90 ].…”

Efficient Ag/CeO2 catalysts for CO oxidation prepared with microwave-assisted biosynthesis

“…Specifically, bioreduction method using plant biomass and microorganism has been developed to prepare Ag NPs as it is an environmentally benign and reliable approach to stable metal NPs [22]. Compared with microorganism-mediated bioreduction, the plant-mediated ones can circumvent the laborious cultivation of microorganisms and they possess higher reaction rate [23][24][25][26] NPs by microwave-assisted bioreduction with Cissus quadrangularis extract [30].…”