title: Preparation of hyperstar polymers with encapsulated Au25(SR)18clusters as recyclable catalysts for nitrophenol reduction.
abstract: A robust approach is developed to prepare hyperstar polymer-Au25(SR)18nanocomposites for catalysis. The synthesis started with atom transfer radical copolymerization of an inimer with a cyclic disulfide-containing methacrylate monomer in a microemulsion to produce hyperbranched copolymers with high molar mass, low polydispersity, and a vital fraction of dangling disulfide groups. The core-shell structured hyperstar polymers were then prepared using hyperbranched copolymers as macroinitiators to polymerize oligo(ethylene glycol) methyl ether methacrylate (Mn= 500) and grow the radiating arms. The hyperstar polymers with disulfide groups were proved to efficiently encapsulate Au25(SR)18nanoclusters through ligand exchange without destroying the fine structure of the Au25(SR)18clusters. The obtained hyperstar-Au25(SR)18nanocomposites showed great stability with no size change after a three-month shelf storage. They were used as efficient catalysts for the catalytic reduction of 4-nitrophenol by NaBH4, showing convenient recovery and reuse without losing catalytic efficiency.
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu and School of Chemistry and Chemical Engineering & Center for Atomic Engineering of Advanced Materials, Anhui University, Hefei 230039, China. zmz@ahu.edu.cn.
authors.forename: Daqiao
authors.initials: D
authors.lastname: Hu
authors.affiliation: School of Chemistry and Chemical Engineering & Center for Atomic Engineering of Advanced Materials, Anhui University, Hefei 230039, China. zmz@ahu.edu.cn.
authors.forename: Shan
authors.initials: S
authors.lastname: Jin
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu.
authors.forename: Yi
authors.identifier: http://orcid.org/0000-0003-2943-5465
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu.
authors.forename: Robert W
authors.initials: RW
authors.lastname: Graff
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering & Center for Atomic Engineering of Advanced Materials, Anhui University, Hefei 230039, China. zmz@ahu.edu.cn.
authors.forename: Manzhou
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556-5670, USA. hgao@nd.edu.
authors.forename: Haifeng
authors.identifier: http://orcid.org/0000-0001-9029-5022
authors.initials: H
authors.lastname: Gao