Phase Stability Investigation of CsPbI3 Perovskite for Solar Cell Application

CsPbI3 perovskite is the most suitable and desired bandgap among all-inorganic perovskite for solar cell applications. However, Poor phase stability is one of the biggest bathers in the further development of CsPbI3 perovskite solar cell. The direct room temperature synthesis is challenging because at room temperature it shows undesired orthorhombic (delta-CsPbI3) structure. Here, we have reported a low-temperature approach to synthesize CsPbI3. We did X-Ray diffraction (XRD) which confirms the formation of CsPbI3 material and also, we found the presence of both cubic and yellow phases. We have studied optical properties of CsPbI3 by measuring Photoluminescence (PL) and UV-visible absorption which shows both cubic (alpha-CsPbI3) and orthorhombic phase contributes in absorption spectra and also display the presence of a large amount of yellow phase in as-synthesized CsPbI3.