文献类型：期刊文献

英文题名：Co-immobilization of Pd and Zn nanoparticles in chitosan/silica membranes for efficient, recyclable catalysts used in ullmann reaction

作者：Liu, Qi[1];Xu, Mengdie[1];Wang, Yudong[1];Feng, Ruokun[1];Yang, Zhen[1];Zuo, Shufeng[1];Qi, Chenze[1];Zeng, Minfeng[1]

机构：[1]Shaoxing Univ, Zhejiang Key Lab Alternat Technol Fine Chem Proc, Shaoxing 312000, Peoples R China

年份：2017

卷号：105

起止页码：575

外文期刊名：INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

收录：SCI-EXPANDED(收录号：WOS:000414882900065)、、EI(收录号：20242616389992)、Scopus(收录号：2-s2.0-85025468094)、WOS

基金：The authors acknowledge the financial support from the National Natural Science Foundation of China (grant number: 11475114), High-level talents further study abroad support plan of Shaoxing City. We would like to thank Prof. Y. Lin (Institute of Materials Science and Department of Chemistry, University of Connecticut) for his helpful discussions.

语种：英文

外文关键词：Chitosan; Porous membrane; Heterogeneous catalyst

外文摘要：In this study, an efficient heterogeneous catalyst including palladium (Pd) and zinc (Zn) nanoparticles supported on chitosan/silica (CS/SiO2) composite membrane is synthesized using partially etching of SiO2 technique..N-2 sorption isotherm results shows that the prepared Pd-Zn@CS/SiO2 (1/1) porous membrane had a BET surface area of 26.50 m(2)/g. High-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS), characterization of the catalyst shows that the Pd nanoparticles (below 5 nm), and Zn aggregates (about 10-15 nm) dispersed well in the CS/SiO2 matrix. Zinc crystal was also detected by X-ray diffraction study and HR-TEM observation. The prepared Pd-Zn@CS/SiO2 membrane catalyst is highly active for Ullmann reductive homocoupling reactions of aryl iodides and aryl bromides, and can be recycled 5 times without significant loss of activities. This work supplies a successful approach to realize Pd catalysts and Zn reducing reagent co-immobilized in the same carrier material with excellent catalytic performances. (C) 2017 Elsevier B.V. All rights reserved.