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Indexed by:期刊论文

Date of Publication:2016-09-01

Journal:JOURNAL OF COLLOID AND INTERFACE SCIENCE

Included Journals:SCIE、EI、PubMed、Scopus

Volume:477

Page Number:1-7

ISSN No.:0021-9797

Key Words:Catalytic reduction; Hydrogenation catalyst; Mesoporous silica; Gold nanomaterials

Abstract:In this study, we demonstrate for the first time that highly branched gold nanostars (AuNSs) and silica coated AuNSs (AuNSs@mSiO(2)) could potentially serve as efficient hydrogenation catalysts. The catalytic activity could be promoted by raising the number of tipped-branches of AuNSs, which reveals that the tips play an important role as active sites. The fabricated sharply-pointed AuNSs benefit the electron transfer from BH4 anions to 4-nitrophenol. Coating AuNSs with mesoporous silica (AuNSs@mSiO(2)) further enhanced the reduction rate and recyclability, and also contributed to reducing the induction period. The AuNSs@mSiO(2) (50-100 nm in diameter) are large enough to be catalytically inactive, but they consist of sharply-pointed tips with the radius of 2.6-3.6 nm, which are rich in coordinately unsaturated sites similar to those of nanoparticles and clusters. Such features in structure and activity would also extend their application range in heterogeneous catalysis. (C) 2016 Elsevier Inc. All rights reserved.