Metal oxide free perovskite solar cell

The flexible perovskite thin film solar cell is fabricated using polypyrrole (PPy) as a binding agent on ITO-PET flexible substrates. PPy as a binding agent and PC61BM as electron transporting material on perovskite (CH₃NH₃PbI₃)-sensitized PEDOT:PSS/ITOPET substrates forms an efficient flexible perovskites solar cell, which demonstrates the reasonably high solar-to-electricity conversion efficiency (g) of ~6.38% with high short circuit current (JSC) of ~15.59 mA/cm² and open circuit voltage (VOC) of ~0.852 V under the light illumination of ~100 mW/cm² (1.5 AM). The transient photocurrent and photovoltage studies explain the improved charge transport time, efficient diffusion coefficient, diffusion length and high charge collection efficiency of the fabricated flexible perovskite solar cells. These enhancements might attribute to active PPy as binding agent along with electron transporting material of PC⁶¹BM. Thus, a reduced recombination and the improved charge transfer properties might render PPy as a costeffective competitor in the flexible perovskites solar cell.