Synthesis of ZnO Nanosheets by a Combined Electrodeposition and Illumination Method

Abstract

To the best of our knowledge there are no reports about synthesizing ZnO nanosheet patterns on zinc foil substrates. ZnO nanosheets with the wurtzite structure have been successfully synthesized via electrochemical wet etching method. Zinc (Zn) foil was used as substrate in this technique. Without using any templates or catalysts, the ZnO nanosheet arrays on a zinc foil substrate were prepared. To adapt ZnO nanosheet structures, the Zn foil was immersed into an admixture of HNO3:ethanol (1:5), at current densities of 127 mA/cm2 at room temperature, and directed to outward light from a 100 W lamp. The constant etching duration is 30 min at room temperature. After etching, the as-prepared products were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). The XRD pattern confirmed that the as-synthesized nanosheets are hexagonal wurtzite structure of polycrystalline structure. The growth direction of the nanosheets is parallel to the (0001) polar direction of ZnO. The optical properties of the ZnO nanosheet arrays were examined by Raman and photoluminescence spectroscopies at room temperature (RT). The photoluminescence spectrum of the as-synthesized nanosheet sample shows only a sharp and strong UV emission centered at 380 nm, which indicates that the ZnO nanosheets on Zn foil are of good optical property.