Spherical Polyelectrolyte Brushes as Templates to Prepare Hollow Silica Spheres Encapsulating Metal Nanoparticles

Integrating hollow silica spheres with metal nanoparticles to fabricate multifunctional hybrid materials has attracted increasing attention in catalysis, detection, and drug delivery. Here, we report a simple and general method to prepare hollow silica spheres encapsulating silver nanoparticles (Ag@SiO2) based on spherical polyelectrolyte brushes (SPB), which consist of a polystyrene core and densely grafted poly (acrylic acid) (PAA) chains. SPB were firstly used as nanoreactors to generate silver nanoparticles in situ and then used as sacrificial templates to prepare hybrid hollow silica spheres. The resulted Ag@SiO2 composites exhibit high catalytic activity and good reusability for the reduction of 4-nitrophenol to 4-aminophenol by NaBH4. More importantly, this developed approach can be extended to the encapsulation of other metal nanoparticles such as gold nanoparticles into the hollow silica spheres. This work demonstrates that SPB are promising candidates for the preparation of hollow spheres with encapsulated metal nanoparticles and the resulted hybrid spheres show great potential applications in catalysis.

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Synthesis and Adsorption Characters of Silica Hollow Spheres

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.184-185.1276 ◽

2012 ◽

Vol 184-185 ◽

pp. 1276-1279

Author(s):

Feng Xia Qiao ◽

Qi Gang Ding ◽

Zhi Ping Lin

Keyword(s):

Solid Phase ◽

Hollow Spheres ◽

Silica Spheres ◽

High Adsorption ◽

Hydrothermal Route ◽

Hollow Silica ◽

Adsorption Performance ◽

Hollow Silica Spheres ◽

Silica Source ◽

Chicken Tissue

A kind of ordered meso-sized hollow silica spherical material was prepared by hydrothermal route using monodispersed cross-linked polymethyl polymer spheres as template, metacrylate tetraethyl orthosilicate as a silica source. The calcination was empolyed for the removing of template and generation silica hollow spherical materials with meso-sized pores. The adsorption performance of the obtained hollow silica spheres was investigated and the results indicated that the obtained hollow silica spheres had high adsorption capacity for sulfadimethoxine. They were sucessfully used as the dispersive adsorbent for matrix solid phase dispersive extraction sulfadimethoxine from chicken tissue with satisfactory results.

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The Preparation of Monodisperse Cationic Polystyrene and its Application to the Synthesis of Hollow Silica Spheres

Australian Journal of Chemistry ◽

10.1071/ch10093 ◽

2010 ◽

Vol 63 (10) ◽

pp. 1418 ◽

Cited By ~ 2

Author(s):

Xin Jin ◽

Shunsheng Cao ◽

Xinhua Yuan ◽

Weiwei Wu ◽

Jie Hu ◽

...

Keyword(s):

Physicochemical Properties ◽

Hollow Spheres ◽

Synthetic Methods ◽

Silica Spheres ◽

Reaction Conditions ◽

Hollow Silica ◽

Hollow Silica Spheres ◽

Soft Templating ◽

Silica Encapsulation ◽

Size And Morphology

The fabrication of hollow spheres with well defined size and morphology has been attracting much attention due to their unique structures and related physicochemical properties. Among the synthetic methods, the template-directed method is particularly interesting and extensively employed to fabricate hollow spheres due to templates available of essentially any size, shape, and chemistry. As a result, a new monodispersed cationic polystyrene (PS) template in this paper was fabricated by using 2-(methacryloyloxy) ethyltrimethylammonium chloride as co-monomer via emulsifier-free polymerization. The template not only can easily be tuned to the size, but can combine the advantages of hard-templating and soft-templating methods. Subsequently, we used cationic PS particles as templates to prepare hollow silica spheres – the results indicated that cationic templates can attract the assembly of tetraethylorthosilicate hydrolyzate on their surface and that the dissolution of templates can be done in the system of silica encapsulation by modification of the reaction conditions.

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Metal Nanoparticles Confined in the Nanospace of Double-Shelled Hollow Silica Spheres for Highly Efficient and Selective Catalysis

Chemistry of Materials ◽

10.1021/acs.chemmater.6b02209 ◽

2016 ◽

Vol 28 (16) ◽

pp. 5596-5600 ◽

Cited By ~ 41

Author(s):

Shunsheng Cao ◽

Jun Chang ◽

Long Fang ◽

Limin Wu

Keyword(s):

Metal Nanoparticles ◽

Silica Spheres ◽

Hollow Silica ◽

Highly Efficient ◽

Hollow Silica Spheres ◽

Selective Catalysis

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Facile synthesis of palladium nanoparticles on hierarchical hollow silica spheres and its catalytic properties in Suzuki-reaction

Royal Society Open Science ◽

10.1098/rsos.180545 ◽

2018 ◽

Vol 5 (9) ◽

pp. 180545 ◽

Cited By ~ 5

Author(s):

Mao Liu ◽

Liuli Wu ◽

Jianjie Han ◽

Xiuhong Xu ◽

Chengyuan He ◽

...

Keyword(s):

Catalytic Activity ◽

Palladium Nanoparticles ◽

Catalytic Properties ◽

Suzuki Reaction ◽

Pd Nanoparticles ◽

High Catalytic Activity ◽

Silica Spheres ◽

Facile Synthesis ◽

Hollow Silica ◽

Hollow Silica Spheres

A novel well-dispersed Pd@HHSS catalyst was synthesized by reduction of Pd(OAc) 2 immobilized on HHSS we reported. When the ratios of Pd/SiO 2 were 5 : 100 and 10 : 100, the Pd nanoparticles size was about 5–10 nm. The Pd@HHSS catalyst (Pd/SiO 2 = 10 : 100) showed high catalytic activity in Suzuki-reaction with yields of 91–99% and the catalyst is reusable after four successive cycles without obvious loss of catalytic activity.

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Preparation of Silica Hollow Spheres Used as Filler for Paper

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.200.339 ◽

2012 ◽

Vol 200 ◽

pp. 339-342 ◽

Cited By ~ 3

Author(s):

Wen Juan Gu ◽

Ying Li ◽

Xiao Hui Zhang

Keyword(s):

Formation Mechanism ◽

Shell Thickness ◽

Sol Gel ◽

Hollow Spheres ◽

Hollow Structure ◽

Silica Spheres ◽

Hollow Silica ◽

Calcination Process ◽

Gel Method ◽

Hollow Silica Spheres

Silica of hollow structure exhibits a number of special characteristic. In this paper, a new way to prepare hollow silica spheres which can be used as filler for paper was reported. In this approach, when silica shells were coated on polyvinylacetate (PVAc) template particles by the sol-gel method, the PVAc cores would be dissolved synchronously, forming hollow spheres. Neither additional dissolution nor a calcination process was needed to remove the PVAc cores. The morphology of the hollow silica spheres was also characterized by TEM. It was shown that the hollow silica spheres with 130-400nm in diameter and 15-35nm in the shell thickness could be synthesized. The possible formation mechanism was also brought forward. The possibility and potential advantages in usage as filler for paper were analyzed theoretically. We confer that this filler can improve the printability of the paper, and reduce its density compared with traditional fillers.

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