Influence of Zinc Oxide Nanostructure Morphology on its Photocatalytic Properties

Background: Zinc oxide (ZnO) is a transparent oxide material with a theoretical bandgap of 3.4 eV, which finds potential applications, including transistors, varistors, solar cells, and other solar applications. The properties of ZnO can be manipulated by controlling its morphology. Methods: The orientation and well-defined nanostructures can be obtained by controlling the growth rates of various ZnO facets by utilizing appropriate capping agents. Here, we report the electrodeposition of ZnO nanostructured thin films in the presence of various capping agents to obtain different ZnO morphologies. The electrodeposition of ZnO nanostructures was carried out on an indium doped tin oxide (ITO) with a glass substrate by using a zinc nitrate (Zn (NO3)2) bath at 70 °C and an applied potential of -1.0 V. To this zinc nitrate bath, capping agents like ammonium fluoride (NH4F) or ethylenediamine (EDA) were added to obtain different ZnO morphologies. These various ZnO morphologies were characterized by scanning electron microscopy. Results: The composition of the nanostructures was analyzed by X-ray diffraction. The photoelectrochemical (PEC) properties of these ZnO nanostructures were measured using a PEC cell. Conclusion: The PEC properties were influenced by different ZnO morphologies.