【摘要】 根据高温下快速成核低温下慢速生长的量子点制备原理,采用胶体化学的方法成功制备了不同粒径的硫化铅半导体量子点.这种方法的特点是以无味和低毒的硫化钠作为制备硫化铅量子点硫的前驱物,因此这是一种量子点的绿色化学合成方法.油酸作为稳定剂控制硫化铅的粒径.采用X射线衍射和高分辨透射电镜表征了量子点的晶体结构、形貌和粒径,采用可见-近红外吸收光谱研究了硫化铅量子点的量子尺寸效应.通过降低油酸的添加量可以促进量子点的生长,得到较大粒径量子点.并探讨了量子点的生长机理.更多还原

【Abstract】 PbS semiconductor quantum dots with different particle sizes were successfully prepared by the colloidal chemistry method according to the theory of fast nucleation at high temperature and slow growth at low temperature. Sodium sulfide was used as a sulfur precursor because it is odorless and is less noxious, which allows it to be classified as a green precursor. Oleic acid was used as a stabilizing agent to control the particle growth and it thus assisted in the formation of monodisperse PbS quantum dots. The crystalline structures, morphology, and particle size of the quantum dots were characterized by powder X-ray diffraction and high-resolution transmission electron microscopy. The quantum size effect of the PbS nanoparticles was analyzed by visible near-infrared (Vis-NIR) absorption spectroscopy. The mean size of the PbS quantum dots increased with a decrease in the concentration of oleic acid. A possible growth mechanism for the PbS nanoparticles was also discussed.更多还原