文献类型：期刊文献

英文题名：Encaging Palladium Nanoparticles in Chitosan Modified Montmorillonite for Efficient, Recyclable Catalysts

作者：Zeng, Minfeng[1];Wang, Yudong[1];Liu, Qi[1];Yuan, Xia[1];Zuo, Shufeng[1];Feng, Ruokun[1];Yang, Jing[2];Wang, Baoyi[2];Qi, Chenze[1];Lin, Yao[3,4]

机构：[1]Shaoxing Univ, Zhejiang Key Lab Alternat Technol Fine Chem Proc, Shaoxing 312000, Peoples R China;[2]Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China;[3]Univ Connecticut, Inst Mat Sci, Polymer Program, Storrs, CT 06269 USA;[4]Univ Connecticut, Dept Chem, Storrs, CT 06269 USA

年份：2016

卷号：8

期号：48

起止页码：33157

外文期刊名：ACS APPLIED MATERIALS & INTERFACES

收录：SCI-EXPANDED(收录号：WOS:000389624600061)、、EI(收录号：20165003124640)、Scopus(收录号：2-s2.0-85002579514)、WOS

基金：The authors acknowledge the financial support from the National Natural Science Foundation of China (Grants 11475114 and 11575117), High-level talents further study abroad support plan of Shaoxing City.

语种：英文

外文关键词：heterogeneous catalysis; palladium; montmorillonite; chitosan; positron annihilation

外文摘要：Metal nanoparticles, once supported by a suitable scaffolding material, can be used as highly efficient heterogeneous catalysts for numerous organic reactions. The challenge, though, is to mitigate the continuous loss of metals from the supporting materials as reactions proceed, so that the catalysts can be recycled multiple times. Herein, we combine the excellent chelating property of chitosan (CS) and remarkable stability of montmorillonite (MMT) into a composite material to support metal catalysts such as palladium (Pd). The in situ reduction of Pd2+ into Pd-0 in the interstices of MMT/CS composites effectively encages the Pd-0 nanoparticles in the porous matrices, while still allowing for reactant and product molecules of relatively small sizes to diffuse in and out the matrices. The prepared Pd-0@MMT/CS catalysts are highly active for the Heck reactions of aromatic halides and alkenes, and can be recycled 30 times without significant loss of activities. Positron annihilation lifetime analysis and other structural characterization methods are implemented to elucidate the unique compartmentalization of metal catalysts in the composite matrices. As both CS and MMT are economical and abundant materials in nature, this approach may facilitate a versatile platform for developing highly recyclable, heterogeneous catalysts containing metal nanoparticles.