Organic molecular dynamics and charge-carrier lifetime in lead iodide perovskite MAPbI <sub>3</sub>
A. Koda, Hirotaka Okabe, M. Hiraishi, R. Kadono, Katelyn A. Dagnall, Joshua J. Choi, Seung-Hun Lee
Abstract
Significance Hybrid organic–inorganic perovskites (HOIPs) are among the most promising materials for next-generation solar cells that combine high efficiency and low cost. The record efficiency of HOIP-based solar cells has reached above 25%, and they can be manufactured using simple solution-processing methods that can be drastically cheaper than the current commercial solar cell technologies. Despite the progress so far, the microscopic mechanism for the high solar cell efficiency in HOIPs is yet to be understood. In this study, we show that the ability of organic molecules to rotate on an appropriate time scale in HOIPs can extend the lifetime of photoexcited charge carriers and lead to higher efficiency. This insight can guide the progress toward improved solar cell performance.