Passivation by pyridine-induced PbI in methylammonium lead iodide perovskites.

Defects at discontinuities of the perovskite lattice limit the performance of the perovskite solar cell (PSC). Lead iodide (PbI) and pyridine have been shown to passivate these defects. We treat methylammonium lead iodide (MAPbI) films with pyridine solutions to investigate the effects of the two passivators.