title: Ultradispersed Palladium Nanoparticles in Three-Dimensional Dendritic Mesoporous Silica Nanospheres: Toward Active and Stable Heterogeneous Catalysts.
abstract: Immobilization of highly monodispersed palladium nanoparticles in colloidal mesoporous silica supports has been successfully achieved. The Pd nanoparticles with a uniform small size of ∼1.2 nm can be homogeneously distributed in individual mesopore channels of amino group-functionalized three-dimensional dendritic mesoporous silica nanospheres (3D-dendritic MSNSs) with a Pd content of ∼2.8%. The 3D-dendritic MSNSs-based nanoreactors show high activity in Suzuki-Miyaura cross-coupling reactions of bromobenzene with phenylboronic acid, obtaining a yield over 99% with 0.075 mol % Pd catalyst at room temperature in the dark within 12 h. More importantly, the excellent catalytic performance can be maintained with a negligible decrease lasting at least six cycles. It further reveals that the mesoporous frameworks of the colloidal silica supports can be well-preserved after four catalytic runs; meanwhile, the Pd nanoparticles in the mesopore channels also can remain the sizes of 1.5±0.3 nm without significant transfer and aggregation. The unique mesostructure of the 3D-dendritic MSNSs with mesopore channels of short length and large diameter is supposed to be the key role in immobilization of active and robust heterogeneous catalysts, and it would have more hopeful prospects in catalytic applications.
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Dengke
authors.initials: D
authors.lastname: Shen
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.|‡College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Yang
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Renyuan
authors.initials: R
authors.lastname: Zhang
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wei
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Li
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Zhenkun
authors.initials: Z
authors.lastname: Sun
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Zhu
authors.affiliation: §Center for Advanced Materials, Qatar University, Doha 2713, Qatar.
authors.forename: Aboubakr M
authors.initials: AM
authors.lastname: Abdullah
authors.affiliation: ‡College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, People's Republic of China.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Al-Enizi
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Elzatahry
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.affiliation: †Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
authors.forename: Dongyuan
authors.initials: D
authors.lastname: Zhao
keywords: colloidal nanospheres; heterogeneous catalysts; mesoporous silica; nanosupports; palladium