Silica-coating of AgI semiconductor nanoparticles
Silica-coating of AgI semiconductor nanoparticles
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DOI：
10.1016/j.colsurfa.2004.10.007
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发表时间：
2004-12
期刊：
影响因子：
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通讯作者：
Yoshio Kobayashi;K. Misawa;M. Takeda;Masaki Kobayashi;M. Satake;Y. Kawazoe;N. Ohuchi;A. Kasuya;M. Konno
中科院分区：
文献类型：
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作者：
Yoshio Kobayashi;K. Misawa;M. Takeda;Masaki Kobayashi;M. Satake;Y. Kawazoe;N. Ohuchi;A. Kasuya;M. Konno
采用Stöber法，在硅烷偶联剂3-巯基丙基三甲氧基硅烷（MPS）的存在下，以二甲胺（DMA）为醇盐水解催化剂，对碘化银纳米粒子进行了表面包覆。以AgClO 4和KI为原料制备了碘化银纳米粒子。用0-2.3×10 - 5 M MPS、11- 20 M水、0-0.1M DMA和0.0004-0.15M原硅酸四乙酯（TEOS）进行二氧化硅涂覆。MPS的加入抑制了游离二氧化硅颗粒的产生，并改善了壳厚度的均匀性。在11- 15 M的水浓度下形成二氧化硅壳，但过量的水（20 M）引起游离二氧化硅颗粒的聚集，并导致凝胶网络的形成。在11 M水和0.01M DMA的条件下，在4.5×10 - 6 M MPS下，随着TEOS浓度从0.0004增加到0.04M，二氧化硅壳层厚度可以从3变化到33.0nm。
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 AgClO4and KI. The silica-coating was performed with 0–2.3×10−5M MPS, 11–20M water, 0–0.1M DMA and 0.0004–0.15M 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 11–15M, but excess water (20M) caused aggregation of free silica particles, and resulted in formation of gel network. The silica shell thickness could be varied from 3 to 33.0nm as the TEOS concentration was increased from 0.0004 to 0.04M at 4.5×10−6M MPS under the condition of 11M water and 0.01M DMA.