Investigation on optical properties and photovoltaic performance of solid-state dye-sensitized solar cells comprised of photoanodes of titanium dioxide nanoparticles calcinated at different temperatures

Abstract

Dye-sensitized solar cells (DSSCs) were constructed using photoanodes of TiO2 nanoparticles (Degussa P25) calcinated at diverse temperatures. The calcinated TiO2 nanoparticles were characterized by X-ray diffraction (XRD) technique and N719 dye anchored TiO2 thin films were subjected to diffuse reflectance spectral and dye desorption studies. The band gaps of TiO2 nanoparticles calcinated at higher temperatures (700 and 900 °C) were shifted to lower energy levels by predominant anatase phase transformation into rutile and increase in the particles size. The performance of DSSCs with TiO2 (Degussa P25) nanofiller incorporated solid-state PEO electrolyte was examined at light intensity of 60 mW cm−2. The DSSC with TiO2 (Degussa P25) nanoparticles photoanode was exhibited overall efficiency of 1.86%, which was ∼4.9 and 9.8-folds greater over the DSSCs having photoanodes of TiO2 nanoparticles calcinated at 700 and 900 °C, respectively. This can be attributed to higher surface area of TiO2 nanoparticles that facilitates higher dye adsorption and predominant anatase phase for favorable electron transfer. The DSSCs stability was confirmed through chronoamperometry experiments.