SYNTHESIS AND PHOTOSENSITIVE PERFORMANCE OF NANOSTRUCTURED ZnO/DYE HYBRID FILM FOR ENERGY CONVERSION

Abstract

The ZnO film prepared by doctor blade method are highly porous in presence of structure directing agent PEG and then can be easily sensitized by various molecules. In the present work, the nanostructured ZnO/dye hybrid film prepared by doctor blade method has been investigated in conductivity and photoconductivity measurements in view of applications in dye-sensitized solar cells (DSSC) and in optoelectronics, since electron transport in these devices plays a decisive role for the electron collection efficiency and therefore for the overall efficiency. The absorption of ZnO film sensitized by Rose Bengal dye (RB) has been studied by UV spectroscopy which indicates that after the dye is adsorbed on the ZnO electrode, its absorption spectra showed redshift in the peak position compared to the absorbance spectra of dye in ethanol. Highly porous ZnO films are found to have high dark conductivity, probably because of a higher n-doping, which is due to higher concentration of Zn atoms in the film. On the other hand, ZnO/RB hybrid film is found to show a much higher sensitivity to illumination with visible light in photoconductivity measurements due to a higher absolute photoconductivity and lower conductivity in the dark.