Ce掺杂ZnO纳米晶的光催化性能研究

Photocatalytic Properties of Ce Doped ZnO Nanocrystalline

以Zn(NO3)3.6H2O、Ce(NO3)3.6H2O为原料,明胶为模板分散剂,采用凝胶模板燃烧法制备纯ZnO和Ce/ZnO纳米晶,利用XRD、TEM、BET、UV-Vis漫反射进行表征。以染料罗丹明B为目标降解物考察了样品的光催化活性。结果表明:产物粒子形状基本为球形,结晶良好,属六方晶系结构。相比纯ZnO,Ce/ZnO对光具有更高的吸收利用率,在紫外和可见光下对罗丹明B的降解能力均有明显提高;随Ce掺杂量的增加,样品的粒径减小,比表面积增大,罗丹明B的降解率相应增大,在紫外和可见光下降解率分别可达98.6%、78.3%,其原因在于Ce掺杂有利于在ZnO纳米粒子中心和表面之间产生电势差,实现光生电子-空穴对的有效分离。

Pure and Ce-doped ZnO nanocrystalline were synthesized by gel-template combustion process using Zn（NO3）2·6H2O and Ce（NO3）3·6H2O as raw materials,gelatin as a based template dispersant.The samples were characterized by XRD,TEM,BET,UV-vis,the photocatlytic activity was studied by degrating Rhodamine B.The results showed that the hexagonal products appeared to be regularly spherical and the crystallinities were rather well.Ce-doped ZnO had stronger absorption and higher degradation activity for rhodamine B than pure ZnO in UV and visible regions.As the Ce doping content increasing,the size of Ce/ZnO nanoparticles size decreased and specific surface area increaed,the degradation rate of rhodamine B increased accordingly,the highest degradation rate was 98.6%,78.3% under UV and visible light,respectively,and its main reason was that Ce-doping was helpful to form the electric potential difference between the center and surface of nanoparticle,thus leading to an effective separation for photoinduced electron and hole pairs.