新型纳米ZnO@SiO2光催化剂降解苯酚溶液的研究

通过化学沉淀、水热反应、煅烧过程制备了新型ZnO@SiO2光催化剂，采用X射线衍射（XRD）、电子透射电镜(TEM)、能谱分析（EDS）、比表面测定实验等手段对产物结构和形貌进行了表征。结果表明，产物为核壳结构的ZnO@SiO2复合颗粒，粒径约为20nm，表面包覆有3nm左右的SiO2壳层。以苯酚为目标降解物，研究新型ZnO@SiO2复合材料在不同pH值溶液中的光催化性能。光催化降解实验结果表明，在酸性（pH 5.8，2.8）或碱性（pH 8.3，12.4）溶液中，ZnO对苯酚的光催化降解率小于10%，而新型核壳结构ZnO@SiO2对苯酚的降解率显著高于ZnO，核壳结构明显改善了光催化剂的稳定性。

Preparation of novel ZnO@ SiO2 nanoparticles and their photocatalytic degradation of phenol

A novel core-shell ZnO@SiO2 photocatalyst has been synthesized by chemical precipitation,hydrothermal reaction and calcination.The resulting composite particles were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),energy dispersive spectrometry(EDS) and surface area measurements.The results showed that the product consisted of core-shell ZnO@SiO2 nanoparticles with a core size of 20 nm coated with 3 nm SiO2 thin shells.The photocatalytic performance of ZnO@SiO2 in aqueous solutions of phenol at varying pH values was investigated.While the photocatalytic degradation of phenol by ZnO was less than 10%,the photocatalytic performance of the composite ZnO@SiO2 particles in both acidic(pH=5.8,2.8) and alkaline(pH=8.3,12.4) solutions of phenol was superior,which suggests they have potential wide applications in pollutant treatment.