The Structural Characterization and Optical Properties of Zinc Oxide Films Synthesized by Electrochemistry Method

Abstract:

Flaky ZnO thin films were electrodeposited from an aqueous solution of zinc nitrate (Zn (NO₃)₂) as electrolyte on ITO glass substrate by cathodic reduction method The effect of electrolyte concentration on the structure, morphology and optical properties of ZnO thin films were studied by X-ray diffraction, scanning electron microscopy and UV-Vis spectrometer. The results show that the ZnO films are of hexagonal wurtzite structure; When the concentration of Zn (NO₃)₂ solution is 0.24 M, the sparse flaky ZnO thin films were prepared and the thickness and length of ZnO flaky are about 50 nm and 1~3 μm, respectively; When the electrolyte concentration is 0.16 M, hexagonal and triangular structures are observed and some lathy and conical ZnO structure start to appear; When the concentration of Zn (NO₃)₂ solution drops to 0.08 M, the matrix of films is still flaky ZnO, but porous structures among the flaky structures appear and the size of conical ZnO has changed, whose bottom diameter reaches 1~3 μm and length is 2~4 μm; UV-Vis absorption test results indicate the absorption peak and the bandgap of the prepared ZnO thin films are about 350 nm and 3.28 eV, respectively.

• Periodical: Materials Science Forum (Volumes 743-744)
• Pages: 926-931
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.743-744.926
• Online since: January 2013
• Authors: Jing Xia Zheng, Xing Guo Zhao, Wei Liang, Jin Bo Xue
• Keywords: Electrochemical Deposition, Morpholoy, Optical Property, ZnO Thin Film

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