Photocatalytic degradation of textile dye by well-aligned arrays of vertically oriented ZnO nanorod films

In the past two decades, the photocatalytic activity of oxide semiconductors (e.g. TiO2, ZnO) for the degradation of hazardous organic compounds in industrial wastewater has been developed [1]. Among oxide semiconductors which have used for photo degradation, ZnO has some privileges to others like; generating H2O2 more efficiently, having high reaction and mineralization rates in addition to having a great amount of active sites with high surface reactivity. On the other hand, ZnO has been used as photocatalyst for the degradation of various pollutants, due to its higher quantum efficiency than TiO2. The use of one-dimensional nanostructured ZnO films has also two advantages in comparison with particles; (1) saving energy and time, and (2) having high surface-to-volume ratio which enhanced the photocatalytic activity [2].