NH 2 CH═NH 2 PbI 3 : An Alternative Organolead Iodide Perovskite Sensitizer for Mesoscopic Solar Cells

A new nearly cubic NH2CH═NH2PbI3 (FAPbI3) perovskite was synthesized for the mesoscopic solar cells. The measured band gap of bulk FAPbI3 is 1.43 eV and it is therefore potentially superior than the CH3NH3PbI3 (MAPbI3) as the light harvester. A homogeneous FAPbI3 perovskite layer was deposited on the TiO2 surface by utilizing the in situ dipping technology. As a result, a high efficiency of 7.5% was achieved using P3HT as the hole transport material. The nearly cubic crystal structure and appropriate band gap render this new FAPbI3 perovskite extremely attractive for next generation high-efficiency low-cost solar cells.