title: Optical characterization of voltage-accelerated degradation in CH3NH3PbI3perovskite solar cells.
abstract: We investigate the performance degradation mechanism of CH3NH3PbI3perovskite solar cells under bias voltage in air and nitrogen atmospheres using photoluminescence and electroluminescence techniques. When applying forward bias, the power conversion efficiency of the solar cells decreased significantly in air, but showed no degradation in nitrogen atmosphere. Time-resolved photoluminescence measurements on these devices revealed that the application of forward bias in air accelerates the generation of non-radiative recombination centers in the perovskite layer buried in the device. We found a negative correlation between the electroluminescence intensity and the injected current intensity in air. The irreversible change of the perovskite grain surface in air initiates the degradation of the perovskite solar cells.
authors.forename: Taketo
authors.initials: T
authors.lastname: Handa
authors.forename: David M
authors.initials: DM
authors.lastname: Tex
authors.forename: Ai
authors.initials: A
authors.lastname: Shimazaki
authors.forename: Tomoko
authors.initials: T
authors.lastname: Aharen
authors.forename: Atsushi
authors.initials: A
authors.lastname: Wakamiya
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Kanemitsu