不同壳层的CdS／ZnS核／壳结构量子点的温度相关荧光性质

Temperature-dependent Luminescence Properties of CdS/ZnS Core/Shell Nanocrystals with Different Shell Thickess

报导了CdS／ZnS纳米晶体（NCs）的制备过程和其光学}生质。通过采用连续离子层吸附和反应技术（SILAR），我们用少量的表面活性剂合成了不同壳层的四个样品，包括CdS核纳米晶以及具有1～3层ZnS壳的CdS／ZnS核／壳结构纳米晶体样品。发现具有一层ZnS壳的CdS／ZnS样品的荧光量子产率大约比未包覆壳层的CdS纳米晶体样品的强11倍。另外，随着壳层的增加（增至两到三层），荧光量子产率呈现下降的趋势。对样品进行了温度相关的光谱测量，发现CdS／ZnS和CdS一样具有特殊的光学特性。

We report the preparation and optical properties of CdS/ZnS nanocrystals （NCs） are reported. By using the successive ion layer adhesion and reaction （SILAR） technique with few surfactants, we synthesized four samples with different shell thickness, including CdS core NCs and CdS/ZnS core/ shell NCs with 1-3 ZnS monolayers （ML） are synthesized. It is observed that the photoluminescence （PL） quantum yield （QY） of the CdS/ZnS core/shell NCs with shell thickness of 1 ML is nearly 11 times more than the bare-core CdS NCs. Moreover, with the shell thickness increased （two or three ML）, the PL QY is decreased. The temperature-dependent optical spectra is measured also, it is bound CdS/ZnS core/shell NCs have particular optical properties as the corresponding bare-core CdS NCs.