One dimensional-ZnO nanostructures: Synthesis, properties and environmental applications

One-dimensional (1D) zinc oxide (ZnO) nanostructures such as rods, wires, belts and tubes have attracted much attention due to their unique physical, chemical, optical, and electrochemical properties enabling remarkable performance in photonics, sensors, photocatalysis, optics and photovoltaic devices. This paper presents a review of recent research in 1D ZnO nanostructures with emphasis on ZnO-based nanowires (NWs or NRs) used as photocatalysts for the degradation of environmental pollutants, particularly textile and industrial dyes, under appropriate light irradiation. Compared to other ZnO nanostructures, the higher aspect ratio (large surface to volume ratio) of 1D ZnO NWs offers highly desirable photocatalytic applications that depend on surface reactions or other phenomena that occur at interface surfaces, and eliminate the cost and requirement for post treatment. In addition, a review of several syntheses, fabrication methods and characterization studies of several types of ZnO NWs is presented. Finally, the photocatalytic degradation of selected dyes is highlighted.