Water-in-CO2 microemulsions as nanoreactors for synthesizing CdS and ZnS nanoparticles in supercritical CO2

被引：83

作者：

Ohde, H ^{[1
]}

Ohde, M ^{[1
]}

Bailey, F ^{[1
]}

Kim, H ^{[1
]}

Wai, CM ^{[1
]}

机构：

[1] Univ Idaho, Dept Chem, Moscow, ID 83844 USA

来源：

NANO LETTERS | 2002年 / 2卷 / 07期

关键词：

D O I：

10.1021/nl010084p

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Semiconductor nanopaparticles of CdS and ZnS were synthesized by mixing two water-in-CO2 microemulsions with one containing S2- ions and the other containing Cd2+ or Zn2+ ions in the water core. Nanoparticle formation was monitored in situ by measuring their absorption spectra in the UV-vis range using a high-pressure fiber-optic system. The size of the nanoparticles formed in the microemulsion was found to depend on the water-to-surfactant ratio (W)- At W = 6 and 12, the band gaps of CdS were calculated to be 3.50 and 3.15 eV, corresponding to particle radii of 1.4 and 1.7 nm, respectively. The ZnS particles synthesized at W = 12 showed a band gap of 4.26 eV, corresponding to a mean particle radius of 1.6 nm. This microemulsion-plus-microemulsion approach offers a simple method for synthesizing various nanoparticles in supercritical CO2 using water-soluble reagents as starting materials.

引用

页码：721 / 724

页数：4