TiO2 Nanorods as electron transport layer for inorganic perovskite solar cells

Abstract

Electron transport layer plays an important role in facilitating the flow of negative charge carriers in Perovskite Solar cells. In the field of Inorganic Perovskites, we have specifically optimised TiO2 as Electron Transport material. TiO2 Nanorods were synthesised by hydrothermal synthesis at different precursor concentration and reaction times. The most optimised result was obtained at 0.7 ml concentration of Titanium butoxide and reaction time of 4 hours. XRD analysis confirmed the structural formation of Rutile TiO2 nanostructures, Optical behaviour were studied by UV-Visible spectroscopy and the bandgap of 2.3 eV in TiO2 nanostructures was obtained. The surface morphology was observed by FESEM, that showed the formation of TiO2 Nanorods. Cyclic Voltammetry and chronoamperometry were performed to evaluate the photocurrent response and long-term photo stability of the thin film. Open circuit potentiometry was done to evaluate the career life time of charge carriers in the TiO2 thin films.Inorganic perovskite CsPbBr3 was prepared by spin coating method and its structure was confirmed by XRD spectroscopy. UV Visible spectroscopy provided the absorption spectra which determined the band gap (2.3 eV) of our perovskite material. The SEM images confirmed the formation of the perovskite cubic structure. Finally, we tried to synthesise the all inorganic perovskite solar cell FTO/TiO2/CsPbBr3/NiO/Ag. The dark current profile of the devise shows similar response as that of a p-n junction diode. But the device failed to show any photo response in presence of light.