溶剂热制备球状ZnS 纳米光催化剂及其光催化性能

以乙二醇为反应介质，醋酸锌（Zn（CH₃COO）₂·2H₂O）和硫脲（（NH₂）2CS）为原料，采用溶剂热法制备了系列ZnS 光催化剂. 考察了不同反应温度、时间对ZnS 的结晶度、比表面积、光吸收性能及其光催化性能的影响. 利用N₂物理吸附（BET）、扫描电镜（SEM）、X 射线衍射（XRD）、紫外可见漫反射光谱（UV-vis DRS）和光致发光谱（PL）对样品进行了表征.以紫外灯（λ=254 nm）为光源，对所得样品进行了光催化降解不同染料的活性测试.研究结果表明，该系列催化剂均具有较好的结晶性能，具有球状形貌.但在140 ℃下处理16 h 的ZnS 样品表现了最高的光催化活性. 光照5 h 后， 染料酸性橙Ⅱ、甲基橙、亚甲基蓝、罗丹明B 的降解率分别达到91.49 %、93.04 %、64.63 %和51.79 %.这主要归于该条件下制备的ZnS 具有比较好的结晶性能、大比表面积和较少的晶格缺陷. 

Solvothermal preparation spherical ZnS nano-photocatalyst and its photocatalytic activity

A series of ZnS photocatalysts were prepared by a solvothermal method with ethylene glyclo as the reaction medium and zninc acetate （Zn （CH₃COO）₂·2H₂O）and thiourea （ （NH₂）2CS）as the precursors. The effects of reaction temperature and time on the crystallnity ， surface area， optic adsorption and photocatalytic performance of the ZnS were investigated. The obtained ZnS samlpes were characterized by N₂ physical adsorption （BET）， scanning electron microscopy （SEM），X-ray diffraction （XRD），UV-vis diffuse reflectance spectra （UV-vis DRS）， and photoluminescence spectroscopy （PL）. The photocatalytic activity of the prepared samples was evaluated by photocatalytic degradation of different dyes under UV light （λ=254 nm） irradiation. The experimental results show that these photocatalysts prepared under solvothermal condition have good crystallinity and spherical morphology. ZnS photocatalyst prepared at 140 ℃ for 16 h shows the highest photocatalytic activity in decomposition of the dyes. After 5 hours ’ light irradiation， the degradation rates of the dyes of acid orange II， methyl orange， methylene blue， and rhodamine B are 91.49 %， 93.04 %， 64.63 % and 51.79 %， respectively. This high photocatalytic activity is mainly attributed to the good crystallnity ， big surface area， and less crystal defects of the ZnS prepared under the optimal condition.