Charge transfer dynamics in a singlet fission organic molecule and organometal perovskite bilayer structure

Abstract

Carrier dynamics between singlet fission molecules and a perovskite were studied using transient absorption measurements on TIPS-pentacene/CH₃NH₃PbI₃ (MAPbI₃) bilayer, pristine MAPbI₃ and TIPS-pentacene films. Ultrafast electron transfer within 1.5 ps is verified to proceed directly from the correlated bound triplet pair states of TIPS-pentacene generated by a singlet fission process to the MAPbI₃ conduction band. Hole transfer from MAPbI₃ to TIPS-pentacene proceeds on a much longer time scale of tens of ns. Our study not only unveils the charge carrier dynamics in a singlet fission molecule/perovskite bilayer structure, but also provides new insights on the design of singlet fission sensitized perovskite solar cells with enhanced performance.