Spray deposition and characterization of nanostructured Li doped NiO thin films forapplication in dye-sensitized solar cells

Abstract

Transparent conducting Li (0–5 wt%) doped NiO thin films with preferentialgrowth along the (111) plane were deposited onto glass substrates bypyrolytic decomposition of nickel nitrate and lithium chloride precursors at500 °C in air. The effect of Li concentration on the structural, optical and transport properties ofNiO thin films was studied by x-ray diffraction (XRD), scanning electron microscopy(SEM), atomic force microscopy (AFM), spectral transmittance, photoluminescence andlinear four-probe resistivity. Activation energies as a function of Li concentration werededuced from the temperature dependent resistivity data measured in the range 300–448 K.The figure of merit was deduced by combining the spectral transmittance and sheetresistance values. The variation in properties of NiO thin film due to Li doping arediscussed based on the above results. A dye-sensitized solar cell has also beenfabricated for the optimized Li doped NiO thin film and the results are presented.