Preparation of ZnO nanoparticles and nanosheets and their application to dye-sensitized solar cells

ZnO nanoparticles which have diameter of 15 nm were prepared by hydrothermal method. ZnO nanosheets were obtained by re-hydrothermal treatment of ZnO nanoparticles. The phase and morphology were investigated by using transmission electron microscope, scanning electron microscope and X-ray diffraction. Also, absorbance spectra were measured by using a UV–vis spectrophotometer. A fill factor of 0.55, short-circuit current of 2.059 mA/cm2, open-circuit voltage of 0.593 V and an overall light to electricity conversion efficiency of 1.55% for the solar cell based on ZnO nanosheets were obtained.