低温湿式化学法制备ZnO纳米棒阵列膜及其光催化活性研究

采用一种简单的低温湿式化学方法,即将预处理好的锌片直接放人5%甲酰胺水溶液中,在65℃烘箱中加热24 h,在锌片基底上成功制备出了大面积具有良好取向的ZnO纳米棒阵列.用XRD、SEM、DRs、PL等测试手段对其进行了表征.研究结果表明,ZnO纳米棒是六方钎锌矿晶,与基底垂直,具有沿(002)晶面择优生长的特征.另外,该阵列薄膜在379 nm附近发出强荧光,禁带宽度为Eg=3.28 eV.以自镇流高压汞灯为光源、以ZnO纳米棒为催化剂处理水中的甲基橙.结果显示,ZnO纳米棒的光催化反应为一级反应,表观速率常数与甲基橙的初始浓度有关.

Preparation and photocatalytic properties of ZnO nanorod array films produced by a low-temperature wet-chemical method

ZnO films made of nanorod arrays with(002) crystal face orientation were prepared by a low-temperature wet-chemical method on a zinc metal substrate.X-ray diffraction(XRD),Scanning Electron Microscopy(SEM),UV-vis diffuse reflection and Photoluminescence(PL) were used to characterize the ZnO nanorod arrays.Photo-degradation of methyl orange in aqueous solution was investigated using the ZnO nanorods as a photocatalyst and a fluorescent high pressure mercury lamp as the light source.The results show that the ZnO nanorods are hexagonal wurtzite structures with highly oriented ZnO(002) crystal faces,which indicates that the as-prepared films were highly c-axis oriented.The room temperature photoluminescence of the as-prepared ZnO films exhibits a strong UV emission centered on 379 nm and a weak emission at about 450 nm.The photocatalytic reaction follows first-order reaction kinetics and the apparent rate constant is related to the initial concentration of methyl orange.