表面包裹和浓度对水溶性II-IV族荧光量子点生长机制和尺寸调控的影响

项目名称： 表面包裹和浓度对水溶性II-IV族荧光量子点生长机制和尺寸调控的影响

项目编号： No.21273237

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 林璋

作者单位： 华南理工大学

项目金额： 80万元

中文摘要： 获得窄光谱、高亮度量子点荧光发射的关键在于受激纳米材料需要有较单一的尺寸分布、高的结晶度和钝化的表面状态，而这些特性的获得在本质上是取决于纳米材料的生长机制和动力学过程。申请人及其合作者在前期工作中通过生长动力学和荧光性质的同步跟踪研究，首次揭示在两种极端的表面包裹下CdS 量子点呈现出不同的生长机制，从而调制材料相应的微结构，使材料最终的发光特性出现不同特征(J. Am. Chem. Soc.)。本项目拟在前期基础上，通过调节不同强度的表面包裹来控制纳米晶的生长，研究纳米材料在两种生长机制并存下的混合衍化规律及其对量子点的微结构调制，阐明生长机制、生长动力学与发光机制之间更为普适性的关联。在此基础上，利用表面包裹调制纳米材料生长机制的原理，对几类II-VI族半导体量子点开展合成科学研究，找到获得窄尺寸分布、高荧光量子产率的材料调控方法。本工作可望为类似量子点的合成和发光性质的研究提供依据

中文关键词： 纳米材料生长动力学；表面包裹；尺寸调控；荧光；量子点

英文摘要： II-VI semiconductor nanocrystals are of great interest for its tunable photoluminescence (PL) properties. To achieve bright and spectrally narrow PL prosperities, fundamentally, it requires the preparation of high quality quantum dots with passivatied surface, focusing size distribution and less lattice defects. It should be noted that, normally these intrinsic characteristics of nanocrystals are closely related to the crystal growth mechanisms of nanocrystals and its kinetic process. Previously (J. Am. Chem. Soc. 2010), the growth of water-soluble mercaptoacetic acid-coated CdS quantum dots (QDs) with two concentrations was selected by candidates and co-authors. It demonstrates that the growths of CdS QDs are controlled by the classic Ostwald ripening mechanism and oriented attachment (OA) growth mechanism, respectively. Obviously different evolution rule of the emission spectra of CdS nanocrystals can further be found between the observed OR and OA based growth. However, since the OR and OA mechanism usually occur simultaneously in crystal growths, the evolution of PL properties could be more complicated in traditional synthesis process. In this work, we aim at introducing different types of surface adsorptions to tune the crystal growth of CdS. The kinetic rules of size, morphology, and lattice structure of C

英文关键词： Nanocrystals growth kinetics；Surface capping；Size controlling；Photoluminescence；Quantum dots