金催化合成硫化锌纳米线及其发光性质的研究

Au catalytic growth and photoluminescence of zinc sulfide nanowires

采用金催化和直接蒸发ZnS粉末的方法，合成出大量具有纤锌矿结构的单晶ZnS纳米线。该纳米线的线径均匀，线形规则，直径在80-120nm，长度约几十微米。研究发现纳米线的形貌对合成的温度很敏感，合成温度的升高会导致纳米线直径的迅速增加。单根纳米线EDS分析表明，ZnS纳米线线体中均匀分布着Au元素，Au元素的掺入是纳米线生长形成后由端部颗粒通过固态扩散进入纳米线中。室温光致发光谱显示：ZnS纳米线有两个发光峰，分别位于446nm和520nm处。446nm的发光峰是由缺陷所致，而520nm左右的发光峰是由Au元素掺杂所致。

Single-crystalline ZnS nanowires with the structure of wurtzite have been synthesized in large-scale by direct evaporation of ZnS powders in the presence of Au film, The nanowires are tens of micrometers in length and 80-120 nm in diameter. The research result shows that the morphology of ZnS nanowires is sensitive to the growth temperature. Higher growth temperature caused rapid increase in the diameter of ZnS nanowires. EDS spectra shows that the Au atom exists in both the body and the tip of as-synthesized ZnS nanowires. The doped Au atom in the nanowire body is tentatively attributed to solid diffusion from the catalytic droplet after the growth process. When excited with a 325 nm ultraviolet light,the nanowires emit light with peaks at 446 nm and about 520 nm which are caused by the defect and the doped-Au atom, respectively.