表面活性剂调制合成纺锤结构氧化锌及其发光性能研究

Synthesis and Luminescence Properties of Spindle-like Zinc Oxide Via Surfactant-assisting Method

采用氯化锌(ZnCl_2)和氨水(NH_3·H_2O)为原料、表面活性剂十六烷基三甲基溴化铵(CTAB)为模板剂,通过水热法可以制备出纺锤结构氧化锌(ZnO)。通过热分析(DTA-TG)和X射线衍射(XRD)分析了的样品的组成结构,同时通过扫描电子显微镜(SEM)和透射电子显微镜(TEM)观察了样品的显微形貌,并初步探讨了其生长机理和光致发光性能。实验结果表明:常温下,由于表面活性剂CTAB的模板作用可以制备出层状沉淀,水热后获得纺锤状ZnO,且样品呈六方纤锌矿结构,具有沿[0001]方向一维生长的特性。随着CTAB浓度的增大,样品的均匀性提高;继续增大CTAB浓度样品发育成六棱柱结构ZnO。提高水热温度和降低ZnCl_2浓度均有利于获得表面光滑晶粒细小的纺锤结构ZnO,长度约为3μm,直径为0.5μm。室温下纺锤结构ZnO具有光致发光性能,样品内部存在晶格缺陷。

Spindle-like zinc oxide was prepared by hydrothermal method using zinc chloride（ZnCl_2）and ammonia（NH_3·H_2O） as raw materials,surfactant cetyltrimethylammonium bromide（CTAB） as template,respectively.The phases of the resulting products were investigated by differential thermal analysis and thermogravimetric analysis（DTA-TG）,and X-ray diffraction（XRD）,while the morphologies were characterized by scanning electron microscope（SEM） and transmission electron microscopy（TEM）,respectively. The possible explanation for the formation structure and the luminescence property were also presented here. The experimental results showed that the layer structure precipitate was formed at room temperature due to the template effect of surfactant CTAB. After hydrothermal treatment,the resulting product was spindle-like zinc oxide with hexagonal wurtzite structure,grew along [0001] axis. The homogeneity of the resulting products was improved with increased the CTAB concentration. However,too higher concentration caused the formation of ZnO with hexagonal prism structure. Increasing the temperature and reducing the ZnCl2 concentration were favorable to obtain the sample with small particle size and smooth surface,which exhibited approximately about 3 μm in length and 0.5 μm in diameter. The spindle-like ZnO has luminescent properties at room temperature,suggesting that the sample has a few crystal defects.