摘要
采用电沉积法在导电玻璃上制备了ZnO薄膜,用X-射线衍射仪和扫描电子显微镜对其进行了表征。研究了各种因素对电沉积ZnO薄膜光催化还原Cr(Ⅵ)的影响。结果表明,空穴清除剂的存在是光催化还原Cr(Ⅵ)的重要条件;酸性介质中,Cr(Ⅵ)光催化还原率最高;Cr(Ⅵ)光催化还原率随Cr(Ⅵ)浓度的减小而增加;NO3-、SO42-和Ni2+等共存离子明显抑制了Cr(Ⅵ)的还原;而Cu2+则有着显著的促进作用。在pH=4.0和c(柠檬酸)为1.2 mmol/L的条件下,经过60 min的反应后,0.1 mmol/LCr(Ⅵ)在ZnO薄膜上的光催化还原率达到96%。
ZnO thin film was cathodically electrodeposited on conducting glass substrate from Zn （ NO3 ） 2aqueous solution and characterized with X- ray diffraction and scanning electron microscope. The influence of operating parameters on the photocatalytic reduction rate for Cr（ Ⅵ ） ions over ZnO thin film was investigated. The results showed that the existence of hole scavenger was necessary for photocatalytic reduction of Cr（ Ⅵ ） ions and the highest photocatalytic reduction rate was obtained in acidic media. The photocatalytic reduction of Cr（ Ⅵ ） ions was inhibited by addition of NO3^-, SO4^-2 and Ni^2＋ species, but promoted by Cu^2＋ species. When initial pH and initial concentration of citric acid was 4.0 and 1.2 mmol/L, respectively, the photocatalytic reduction rate for Cr （Ⅵ ） ions （ 0. 1 mmol/L） reached 96% after lh irradiation.
出处
《电镀与精饰》
CAS
北大核心
2009年第5期9-12,共4页
Plating & Finishing
关键词
氧化锌
光催化还原
Cr(Ⅵ)
zinc oxide
photocatalytic reduction
hexavalent chromium
