纳米ZnO薄膜的制备及其可见光催化降解甲基橙

采用溶胶-凝胶方法制备ZnO透明溶胶, 在铝箔上涂膜后经500 ℃处理制得具有可见光响应的纳米ZnO薄膜光催化剂. 以甲基橙模拟有机污染物, 在可见光下研究了薄膜的降解性能, 结果表明, 用一片有效面积为200 cm2的ZnO/Al薄膜作为催化剂, 甲基橙的降解率达到96.3％, 比ZnO负载在玻璃上制得的ZnO/glass薄膜催化剂活性高得多. 采用扫描电镜与原子力显微镜对ZnO/Al薄膜制备条件进行了表征, 结果发现多孔ZnO/Al薄膜比致密ZnO/Al薄膜具有更高的活性, 实验制备的具有高活性的ZnO/Al薄膜颗粒平均直径为52.2 nm. 采用本方法制备的ZnO/Al薄膜是一种具有应用前景的, 能在可见光下降解有机物的有效光催化剂.

Preparation of Visible-light Response Nano-sized ZnO Film and Its Photocatalytic Degradation to Methyl Orange

Transparent ZnO sols have been prepared by sol-gel method and deposited on aluminum foil substrates by dip-coating method, and then calcinated at 500 ℃ to obtain visible-light response nano-sized ZnO film photocatalysts.The films have been applied in photocatalytic degradation of methyl orange as model of organic pollutant under visible-light irradiation. The results show that the degradation of methyl orange reaches 96.3% by using a piece of ZnO/Al thin film as photocatalyst with an efficient irradiation area of 200 cm2, which is higher than that of ZnO/glass film. The films have been characterized by means of scanning electron microscopy and atomic force microscope, which indicated that photocatalytic activity of porous ZnO films should be higher than that of compact cumulate ZnO films;and the ZnO/Al film with high visible light response is formed by a layer ofZnO nano-sized particles with average diameter of 52.2 nm. The results suggest that the ZnO-supported commercial aluminum foil is a promising and efficient thin film catalyst to degrade organic pollutants under visible light irradiation.