Modified photoelectric properties of CH₃NH₃PbI₃ via surface passivation induced by argon ions bombardment

Many investigations have revealed that PbI₂ plays a passivated role to reduce the charge recombination in the perovskite films. However, due to the random distribution of PbI₂ in perovskite films, the passivation effect is blanketed to some extent. In this work, we use the argon ions bombardment to deliberately induce the PbI₂ layer at the surface of perovskite films and investigate the photoelectric performance of samples. It is found that the PbI₂ layer at the surface can passivate the defects effectively, leading to an improvement of the photoconduction by an order of magnitude as well as the responsivity by >4 times under the irradiation of 405 nm light. The bombardment provides an effective method for perovskite surface passivation and optimizing the performances of perovskite-based photoelectric devices.