TY - JOUR
T1 - Silica-coating of AgI semiconductor nanoparticles
AU - Kobayashi, Yoshio
AU - Misawa, Kiyoto
AU - Takeda, Motohiro
AU - Kobayashi, Masaki
AU - Satake, Masanobu
AU - Kawazoe, Yoshiyuki
AU - Ohuchi, Noriaki
AU - Kasuya, Atsuo
AU - Konno, Mikio
N1 - Funding Information:
This research was partially supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan (Grant-in-Aid for the COE project, Giant Molecules and Complex Systems), and by the Ministry of Health, Labor and Welfare of Japan.
PY - 2004/12/20
Y1 - 2004/12/20
N2 - A method for silica-coating of AgI nanoparticles is proposed, which applies Stöber method in the presence of a silane coupling agent, 3-mercaptopropyltrimethoxysilane (MPS), with the use of dimethylamine (DMA) catalyst for alkoxide hydrolysis. The AgI nanoparticles were prepared from AgClO4 and KI. The silica-coating was performed with 0-2.3 × 10-5 M MPS, 11-20 M water, 0-0.1 M DMA and 0.0004-0.15 M tetraethyl orthosilicate (TEOS). The addition of MPS suppressed generation of free silica particles and improved uniformity of shell thickness. Silica shells were formed at water concentrations of 11-15 M, but excess water (20 M) caused aggregation of free silica particles, and resulted in formation of gel network. The silica shell thickness could be varied from 3 to 33.0 nm as the TEOS concentration was increased from 0.0004 to 0.04 M at 4.5 × 10-6 M MPS under the condition of 11 M water and 0.01 M DMA.
AB - A method for silica-coating of AgI nanoparticles is proposed, which applies Stöber method in the presence of a silane coupling agent, 3-mercaptopropyltrimethoxysilane (MPS), with the use of dimethylamine (DMA) catalyst for alkoxide hydrolysis. The AgI nanoparticles were prepared from AgClO4 and KI. The silica-coating was performed with 0-2.3 × 10-5 M MPS, 11-20 M water, 0-0.1 M DMA and 0.0004-0.15 M tetraethyl orthosilicate (TEOS). The addition of MPS suppressed generation of free silica particles and improved uniformity of shell thickness. Silica shells were formed at water concentrations of 11-15 M, but excess water (20 M) caused aggregation of free silica particles, and resulted in formation of gel network. The silica shell thickness could be varied from 3 to 33.0 nm as the TEOS concentration was increased from 0.0004 to 0.04 M at 4.5 × 10-6 M MPS under the condition of 11 M water and 0.01 M DMA.
KW - AgI
KW - Core-shell
KW - Nanoparticle
KW - Silica coating
KW - Sol-gel
KW - Stöber method
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U2 - 10.1016/j.colsurfa.2004.10.007
DO - 10.1016/j.colsurfa.2004.10.007
M3 - Article
AN - SCOPUS:9644303436
SN - 0927-7757
VL - 251
SP - 197
EP - 201
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
IS - 1-3
ER -