Impact of ionizing radiation doses on nanocrystalline TiO2 layer in DSSC’s photoanode film

Abstract

In dye-sensitized solar cell (DSSC) properties of nanocrystalline oxide layer of photoanode may changes when exposed to ionization radiation environment which may leads to change the cell performance. In this study, 10 µm thick TiO2 (Degussa-P25) was deposited as a photoanode film on microscopic glass slide with the doctor-blade coating. The deposited film was subjected to different gamma (γ) radiation doses (0–20 kGy) to study the effect of ionizing radiation on morphological, structural, optical and compositional characteristics of the film. At 10 kGy dose, dislocation density (DD), strain, crystallites per unit surface area (CPSA), specific surface area (SSA) of anatase phase (1 0 1) of the film were decreased abruptly, conversely, crystal size and morphology index (MI) were increased at the same radiation dose slowly. UV-Vis-NIR spectroscopy results showed that in irradiated photoanode film the light transmittance and absorption depth were decreased, whereas, absorption and absorption coefficient were increased beyond the visible wavelength. The optical band gap of the irradiated film was increased by 12.5% when the gamma radiation dose increased from 0 kGy to 20 kGy. Thus, the irradiation induced changes in physio-chemical properties of nanocrystalline photoanode film may affect the DSSC cell performance.