1. Charge Injection Mechanism at Heterointerfaces in CH3NH3PbI3 Perovskite Solar Cells Revealed by Simultaneous Time-Resolved Photoluminescence and Photocurrent Measurements
- Author
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Ai Shimazaki, Yoshihiko Kanemitsu, Taketo Handa, David M. Tex, and Atsushi Wakamiya
- Subjects
Photocurrent ,Materials science ,Photoluminescence ,business.industry ,Slowdown ,Photovoltaic system ,Heterojunction ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Optoelectronics ,General Materials Science ,Quantum efficiency ,Physical and Theoretical Chemistry ,0210 nano-technology ,business ,Excitation ,Perovskite (structure) - Abstract
Organic–inorganic hybrid perovskite solar cells are attracting much attention due to their excellent photovoltaic properties. In these multilayered structures, the device performance is determined by complicated carrier dynamics. Here, we studied photocarrier recombination and injection dynamics in CH3NH3PbI3 perovskite solar cells using time-resolved photoluminescence (PL) and photocurrent (PC) measurements. It is found that a peculiar slowdown in the PL decay time constants of the perovskite layer occurs for higher excitation powers, followed by a decrease of the external quantum efficiency for PC. This indicates that a carrier-injection bottleneck exists at the heterojunction interfaces, which limits the photovoltaic performance of the device in concentrator applications. We conclude that the carrier-injection rate is sensitive to the photogenerated carrier density, and the carrier-injection bottleneck strongly enhances recombination losses of photocarriers in the perovskite layer at high excitation co...
- Published
- 2017