Unveiling charge-transfer dynamics at singlet fission layer/hybrid perovskite interface

• Main Authors: Xiao, Xingchi, Cheng, Liang, Bao, Di, Tan, Qi Ying, Salim, Teddy, Soci, Cesare, Chia, Elbert E. M., Lam, Yeng Ming
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2023
• Subjects: Engineering::Materials; Singlet Fission; Perovskite
• Online Access: https://hdl.handle.net/10356/171405
• Institution: Nanyang Technological University

Singlet fission (SF) materials have been applied in various types of solar cells to pursue higher power conversion efficiency (PCE) beyond the Shockley-Queisser (SQ) limit. SF implementation in perovskite solar cells has not been successfully realized yet due to the insufficient understanding of the SF/perovskite heterojunctions. In this work, we attempt to elucidate the charge dynamics of an SF/perovskite system by incorporating a well-known SF molecule, TIPS-pentacene, and a triple-cation perovskite Cs0.05(FA0.85MA0.15)0.95PbI2.55Br0.45, owing to their well-matched energy structures. The transient absorption spectra and kinetic fitting plots suggest an electron-transfer process from the triplet state of TIPS-pentacene to perovskite in the picosecond regime, which increases the carrier density by 20% in the perovskite layer. This work confirms the existence of an electron-transfer process between the SF material and perovskite, providing a pathway to SF-enhanced perovskite solar cells.