摘要
以乙酸锌和氨水为原料,采用微波水热法成功制备出了花状ZnO光催化剂。探讨了溶液Zn2+初始浓度、pH值和微波加热时间对ZnO物相、形貌及光催化性能的影响。XRD表明制备的样品均为纤锌矿结构,晶型完整且部分ZnO样品晶粒沿(002)晶面发生了取向性生长;SEM表明pH值对ZnO形貌有着重要影响,pH值过低(pH<10.0)时,无法形成花状ZnO,pH过高(pH>10.7)时,花状ZnO'花瓣'会变形甚至溶解;UV-Vis表明制备的ZnO样品的吸收带均发生了红移,拓宽了光催化剂的吸收波长范围;反应条件对ZnO光催化性能的影响主次关系为:pH值>Zn2+初始浓度>微波加热时间,较优工艺及工艺参数为:初始反应Zn2+浓度为0.15 mol/L,pH值为10.5,微波加热时间为2.5 h,较优样品在紫外光辐照4 h后对亚甲基蓝溶液的降解率为85.90%。
The flower-like ZnO photocatalyst was successfully prepared by microwave hydrothermal method using zinc acetate and ammonia as starting materials.The effects of Zn2+initial solubility,pH value and microwave heating time on the phase,morphology and photocatalytic activity of ZnO were investigated.XRD analysis shows that integral crystallized ZnO of the hexagonal wurtzite structure is prepared with orientated growth along(002).SEM results show that the pH value has an important influence on the morphology of ZnO.Too low pH value(pH<10.0)can not form the flower-like ZnO while excessive pH(pH>10.7)dissolves the flower-like ZnO.UV-Vis analysis indicates that all the absorption bands of the prepared ZnO samples undergo red shift,which broadens the absorption wavelength range of the photocatalyst.The influence order of the photocatalytic properties about ZnO is as follows:pH>Zn2+initial solubility>microwave heating time.The optimum technological and technological parameters are as follows:the initial reaction temperature is 0.15 mol/L,the pH value is 10.5,and the microwave heating time is 2.5 h.The degradation rate of the methylene blue solution of the superior sample is 85.9%after illuminated by ultraviolet light for 4 h.
作者
徐晓虹
余佳惠
吴建锋
李晓雪
金昊
杜怿鑫
XU Xiao-hong;YU Jia-hui;WU Jian-feng;LI Xiao-xue;JIN Hao;DU Yi-xin(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China)
出处
《武汉理工大学学报》
CAS
北大核心
2018年第5期7-13,共7页
Journal of Wuhan University of Technology
基金
国家重点研发计划(2017YFB0310905)
关键词
花状ZnO
微波水热法
光催化
结构与性能
flower-like ZnO
microwave hydrothermal method
photocatalysis
microstructure and properties
