Type-I and type-II nanoscale heterostructures based on CdTe nanocrystals: A comparative study

被引：79

作者：

Dorfs, Dirk ^{[1
]}

Franzl, Thomas ^{[2
,3
]}

Osovsky, Ruth ^{[4
]}

Brumer, Maya ^{[4
]}

Lifshitz, Eftat ^{[4
]}

Klar, Thomas A. ^{[2
,3
,5
,6
]}

Eychmueller, Alexander ^{[1
]}

机构：

[1] Tech Univ Dresden, D-01069 Dresden, Germany

[2] Univ Munich, Dept Phys, Photon & Optoelect Grp, D-80799 Munich, Germany

[3] Univ Munich, CeNS, D-80799 Munich, Germany

[4] Technion Israel Inst Technol, Dept Chem, IL-32000 Haifa, Israel

[5] Tech Univ Ilmenau, Inst Phys, D-98684 Ilmenau, Germany

[6] Tech Univ Ilmenau, Inst Micro & Nanotechnol, D-98684 Ilmenau, Germany

来源：

SMALL | 2008年 / 4卷 / 08期

关键词：

core/shell materials; heterostructures; quantum dots semiconductor; nanocrystals;

D O I：

10.1002/smll.200800287

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

A comparative study of CdTe/CdS core/shell nanocrystals and CdTe/CdSe core/shell nanocrystals was investigated. a type-II structure is formed in the case of the CdSe containing system, which is proven by a red-shift of the absorption and emission spectra and also by a prolonged radiative lifetime. The CdSe-free nanoparticles show Type-I behavior, that is, only a small red shift and an unchanged radiative life time. The CdSe/CdS nanocrystals were precipitated out of the crude reaction mixture by dissolving in toluene and precipitating with isopropanol. The necessary amount of precursor solutions for the coating steps was calculated from the particle size and concentration, both of which can be obtained from the absorption spectra. Time resolved photoluminescence measurements were taken with a microchannel plate and time correlated single-photon counting.

引用

页码：1148 / 1152

页数：5

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