Interfacial modification by multifunctional octocrylene for high efficiency and stable planar perovskite solar cells.

Interfacial modification of the perovskite surface with octocrylene (2-ethylhexyl-2-cyano-3,3-diphenyl-2-propenoate, OCT) is capable of enhancing humidity stability and passivating the defects of perovskite films. In this study, octocrylene can be attached to the surface of the perovskite, and the carbonyl group (C[double bond, length as m-dash]O) in octocrylene achieved excellent passivation through the Lewis base electron passivation of Pb2+ ions. By increasing the concentration of the octocrylene/IPA solution, the modified device exhibited an optimal PCE of 20.54% and a steady state output PCE of 19.75%. This study shows that the introduction of octocrylene in the preparation of perovskite could effectively enhance the performance of perovskite solar cells.