Improved efficiency and stability of organic-inorganic hybrid perovskite solar cell via dithizone surface passivation effect

Passivating chemicals are recognized as an effective strategy to eliminate the defects inside and on the surface of the perovskite absorber. In this study, dithizone (DTZ) was explored as the passivation agent to modify the perovskite surface and improve the performance of the solar cells. DTZ contains the –NH, –SH, and benzene rings, where the –NH and –SH can interact with Pb2+ while the benzene can stabilize the perovskite. It is demonstrated that DTZ could effectively promote the quality of the perovskite films by reducing the excess lead iodide and defects on the surface, and eventually suppressing the non-radiative carrier recombination. Furthermore, the introduction of the DTZ interface can optimize the band alignment to facilitate the hole collection. Resultantly, device parameters, including current density, open-circuit voltage, fill factor, and the power conversion efficiency have been enhanced substantially from 16.96% to 19.67%. Meanwhile, the shelf stability also exhibited a considerable promotion.