Dark-red-emitting CdTe/Cd1-xZnxS core/shell quantum dots: preparation and properties
Dark-red-emitting CdTe/Cd1-xZnxS core/shell quantum dots: preparation and properties
复制标题
深红光发射CdTe/Cd1-xZnxS核/壳量子点的制备与性能
作者：
P. Yang;N. Murase
CdTe 纳米晶体（NC）是通过有机合成制备的。 CdTe NC 的生长和性能很大程度上取决于制备条件。在十八烯和十四烷基膦酸(TDPA)的反应体系中，生长缓慢。使用十八烷基膦酸 (ODPA)-CdO 或 TDPA-CdO 作为前体，在三辛胺 (TOA) 中制备出具有立方形貌的 CdTe NC。 TOA 和 ODPA 系统产生具有高光致发光 (PL) 效率 (12%) 的 NC。 CdTe 核上的 CdxZn1-xS 壳涂层产生可调谐的深红色 PL（630-670nm）。 CdTe 核的形貌和 PL 性能受到壳涂层的极大影响，这决定了 CdTe/CdxZn1-xS NC 的性能。小型 CdTe NC 很容易涂覆 CdxZn1-xS 壳。所得核/壳 NC 显示出球形形态。然而，当使用大的 CdTe 核时，壳的生长变得缓慢。这归因于具有类立方形态的核心。 CdS 中间层对于 CdTe/CdxZn1-xS NCs 的形成起着重要作用，因为实验结果表明很难用 ZnS 壳包覆 CdTe NCs。核/壳 NC 受益于 CdxZn1-xS 复合壳，因为通过类似程序创建的 CdTe/CdS NC 显示出较低的 PL 效率。版权所有 © 2012 约翰·威利父子有限公司
CdTe nanocrystals (NCs) were fabricated through an organic synthesis. The growth and properties of CdTe NCs depended strongly on the preparation conditions. In a reaction system of octadecene and tetradecylphosphonic acid (TDPA), the growth was slow. CdTe NCs with cubic‐like morphology were created in trioctylamine (TOA) using octadecylphosphonic acid (ODPA)‐CdO or TDPA‐CdO as precursors. The TOA and ODPA system gives rise to NCs with high photoluminescence (PL) efficiencies (12%). A CdxZn1‐xS shell coating on the CdTe core, gave rise to tunable dark red PL (630–670 nm). The morphology and PL properties of the CdTe cores were drastically affected by shell coating and this determined the properties of CdTe/CdxZn1‐xS NCs. Small CdTe NCs were easily coated with CdxZn1‐xS shells. The resulting core/shell NCs revealed a spherical morphology. However, shell growth became slow when large CdTe cores were used. This is ascribed to the cores with a cubic‐like morphology. CdS interlayer plays an important role for the formation of the CdTe/CdxZn1‐xS NCs because the experimental result indicated it is difficult to coat CdTe NCs with a ZnS shell. The core/shell NCs benefited from a CdxZn1‐xS composite shell because CdTe/CdS NCs created via a similar procedure revealed a low PL efficiency. Copyright © 2012 John Wiley & Sons, Ltd.