化学学报 ›› 2017, Vol. 75 ›› Issue (3): 300-306.DOI: 10.6023/A16100543 上一篇    下一篇

研究论文

持续注射法合成InPZnS/ZnS核壳结构量子点的研究

黄璐a, 李志春a, 黄寿强a, Peter Reissb, 李良a   

  1. a 上海交通大学环境科学与工程学院 上海 200240;
    b 法国原子能中心 法国 38054
  • 投稿日期:2016-10-13 修回日期:2016-12-27 发布日期:2017-01-18
  • 通讯作者: 李良,E-mail:liangli117@sjtu.edu.cn;Tel.:021-54747567;Fax:021-54747567 E-mail:liangli117@sjtu.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos.B21271179,21607101)资助.

Synthesis of InPZnS/ZnS Quantum Dots by Continuous Injection of Phosphorus Precursor

Huang Lua, Li Zhichuna, Huang Shouqianga, Peter Reissb, Li Lianga   

  1. a School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240;
    b CEA Grenoble, 17 rue des Martyrs, Grenoble 38054, France
  • Received:2016-10-13 Revised:2016-12-27 Published:2017-01-18
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. B21271179, 21607101).

高质量、大尺寸的磷化铟量子点(InP quantum dots)的制备对其在生物荧光标记等领域的应用有重大的意义.提出一种持续注射法合成InPZnS/ZnS核壳结构量子点.首先将磷化锌和硫酸反应生成的磷化氢持续注入高温铟前体溶液中,并在反应开始加入适量的锌和硫前体,可制得合金结构的InPZnS核,其量子产率达9%.该方法无需加锌回流处理,可直接升温包覆ZnS壳层,成功制备出发光波长至680 nm且量子产率接近50%的InPZnS/ZnS核壳结构量子点.同时系统地研究了反应物配比对量子点粒径的影响规律,结果表明:通过调控反应物配比可合成不同粒径的InP量子点,其光谱范围几乎可覆盖整个可见光区,甚至到近红外区.通过吸收光谱、荧光光谱、透射电子显微镜、X射线衍射仪和X射线能谱仪考察了所制备量子点的光学特性和形貌结构.最后,采用其它磷前体探究了此方法的通用性,通过注射泵将三(二乙氨基)膦持续注入到高温铟前体溶液中,同样制备出较大尺寸的InP量子点,其发光波长至710 nm.

关键词: InPZnS/ZnS, 核壳型量子点, 量子产率, 光学特性, 持续注射法

InP quantum dots (QDs) are regarded as the most desirable candidate to replace the role of CdSe QDs in the applications of bio-labeling, LEDs, solar cells, etc, because InP is more environmentally friendly compared to Cd based QDs, and could also offer a tunable emission from blue to near-infrared. Nevertheless, the studies and applications of InP QDs are rather sparse in comparison with CdSe QDs, which are principally caused by significant difficulties in its synthesis. In this report, we developed a novel method for the synthesis of InPZnS/ZnS QDs by using zinc phosphide as phosphorus precursor, and the zinc and sulfur precursors were also added at the start of reaction, which allows the continuous injection of phosphine gas into the reaction, resulting in high quality InPZnS/ZnS quantum dots with emission up to 680 nm. The core synthesis and shell coating were separated by controlling the reaction temperature. During the first 30 minutes, the temperature of reaction solution was kept at 250℃ to grow the InPZnS core QDs. Then, the coating of ZnS shell was happened and kept about 1 hour to guarantee the complete decomposition of 1-dodecanethiol (DDT) after the reaction temperature was increased to 300℃. The biggest advantage of this synthetic method is the tunable emission region from blue to near-infrared. The effects of reaction parameters were systematically investigated. We observed that the molar ratio of In:myristic acid (MA) and that of In:Zn (S) had significant influences on the size of the InP QDs. The structure of InPZnS/ZnS QDs was confirmed by transmission electron microscope (TEM), X-ray powder diffraction (XRD), and energy dispersive X-ray analyzer (EDX). TEM characterization indicated the final core/shell InPZnS/ZnS QDs were good monodispersity with an average size of 7 nm. Furthermore, we investigated the versatility of this method by using other phosphorus precursor. The injection pump leaded to a continuous supply of phosphorus precursor on a timescale and reacted with indium precursor to form InP QDs. The final sample showed an emission at 710 nm. The present method gives access to larger sized InP QDs, making it prosperous for applications in biological labeling.

Key words: InPZnS/ZnS, core/shell QDs, quantum yield, optical property, continuous injection