Effect of reaction time and applied voltage on the structural and optical properties of Al-doped ZnO nanostructures electrochemically deposited on indium-tin-oxide-coated glass substrates

Al-doped ZnO (AZO) nanostructures were electrochemically formed on indium-tin-oxide (ITO)-coated glass substrates. Scanning electron microscopy images showed that the density of the AZO nanostructures increased with increasing reaction time and applied voltage. X-ray diffraction patterns showed that the intensities corresponding to the (002) diffraction peak of the AZO nanostructures deposited at higher voltages of -1.3 and -1.4 V were relatively higher than those deposited at lower voltages of -1.1 and -1.2 V. Photoluminescence (PL) spectra for the AZO nanostructures formed on the ITO-coated glass substrates showed that the PL peak intensity related to the defects for the AZO nanostructures increased with increasing reaction time due to an increase in the thickness of the nanosheets.