Synthesis of ZnO nanocrystals and their application to photocatalytic degradation for eriochrome black T
In this paper, we report the synthesis of nanostructured ZnO materials by chemical vapor deposition (CVD) method and the application in photocatalysis degradation for eriochrome black T (EBT: sodium (4z)-4-(1-hydroxynaphthalen-2-yl) hydrazinylidene-7-nitro-3-oxo-naphthalene -1-sulfonate). The morphology and structure were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray powder diffraction （XRD) measurements. The photocatalytic degradation of EBT was examined in aqueous ZnO dispersions under UV light irradiation. There are many parameters that will affect the degradation efficiency in the process of photocatalytic degradation of EBT. In order to reduce the times of experiments and acquire the optimum combination of parameters for maximum degradation efficiency, the systematical and analytical evaluation method of orthogonal experiment designed is introduced. An L25(56) orthogonal array was employed to evaluate the effects of the parameters on the degradation efficiency of ZnO nanocrystal for EBT. The results show that in certain conditions EBT can be degraded completely, which suggests that ZnO is an effective catalyst for the photodegradation of EBT. Besides, we achieved the optimum parameters for the degradation of EBT, i.e. ZnO loading: 5 g/L, light intensity: 120 w, temperature: 20℃, the degradation time: 120 min, the concentration of EBT: 10 mg/L, the pH value of the solution: 4. The confirmation experiments reveals that about 95％ of EBT was degraded in 20 minutes and they were completely degraded within 30 minutes, which indicates that the ZnO nanocrystals deposited by CVD method is quite efficient in the degradation for EBT. They may have potential applications in the treatment of contaminated water.
ZnO nanocrystals CVD growth method Photocatalytic degradation EBT Orthogonal array experiment
何发泉 赵亚溥
中国科学院力学研究所
国际会议
成都
英文
2007-11-19（万方平台首次上网日期，不代表论文的发表时间）