Electron Transfer from Triplet State of TIPS-Pentacene Generated by Singlet Fission Processes to CHNHPbI Perovskite.

To reveal the applicability of singlet fission processes in perovskite solar cell, we investigated electron transfer from TIPS-pentacene to CHNHPbI (MAPbI) perovskite in film phase. Through the observation of the shorter fluorescence lifetime in TIPS-pentacene/MAPbI perovskite bilayer film (5 ns) compared with pristine MAPbI perovskite film (20 ns), we verified electron-transfer processes between TIPS-pentacene and MAPbI perovskite. Furthermore, the observation of singlet fission processes, a faster decay rate, TIPS-pentacene cations, and the analysis of kinetic profiles of the intensity ratio between 500 and 525 nm in the TA spectra of the TIPS-pentacene/MAPbI perovskite bilayer film indicate that electron transfer occurs from triplet state of TIPS-pentacene generated by singlet fission processes to MAPbI perovskite conduction band. We believe that our results can provide useful information on the design of solar cells sensitized by singlet fission processes and pave the way for new types of perovskite solar cells.