ZnS纳米球的水热法制备及其光催化性能研究

在表面活性剂十六烷基三甲基溴化铵(CTAB)的辅助下,以乙酸锌为锌源,硫脲(NH₂)₂CS为硫源,使用水热法通过改变反应时间,成功制备了不同粒径的ZnS球状颗粒.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线能谱,高分辨透射电子显微镜(HRTEM))、紫外可见分光光谱和光致发光谱(PL)等测试手段对样品的晶体结构、形貌、光学性质进行了分析.通过对不同粒径的ZnS纳米颗粒对亚甲基蓝的光催化降解的催化活性进行了评估.实验结果表明:在表面活性剂CTAB的作用下,随着反应时间的增加,生成的ZnS晶核生长成纳米颗粒,然后ZnS纳米颗粒将进一步发生团聚从而形成平均粒径超过500nm的ZnS纳米球,但制备的ZnS产物的晶体结构均为立方纤锌矿结构.随着ZnS粒径的增加,样品的紫外吸收峰从418nm逐渐蓝移到362nm,而PL发射峰位的峰强随着粒径的增大而增强.光催化结果显示,反应12h制备的ZnS纳米球的光催化性能最佳.

Fabrication of ZnS Nanoparticles with Enhanced Photocatalytic Activity by Hydrothermal Method

Under the role of CTAB, different size ZnS sphericallike particles were fabricated by hydrothermal method. The crystal structure, morphology, composition and optical property of the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), X-ray energy spectrum (EDS), UV-Vis absorption spectrum and photoluminescence spectrum (PL). Photocatalytic activities were evaluated by degradation of MB solution. The results show that ZnS nanoparticles were formed by aggregation of crystal nucleus under the role of CTAB. With the increase of reaction time, the size of ZnS particles increased to 500 nm, however, the crystal structure of product has no change. With the increase of particle size, the UV-Vis absorption peak of samples shifted from 418 to 362 nm and the PLintensity further increased. Finally, the photocatalytic activity presented that fabricated ZnSnanoparticles with reaction time 12 h showed best photcatalytic performance.