Proceedings of Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP24)
Publication date: 18th October 2023
Perovskite solar cells (PSCs) have demonstrated exceptional performance, yet their toxicity is problematic due to lead content, which may pose a serious threat to the environment and human health. This study aims to resolve the lead leakage problem without compromising the high photovoltaic efficiency through interfacial passivation using crown ether materials. Herein, we applied benzo-18-crowns-6-ether (B18C6) between the perovskite and hole transport material for capturing Pb2+ ions through host-guest complexation, preventing Pb leakage into the surrounding environment. Our candidate materials were identified through the analysis of binding Pb2+ ions by density functional theory calculations. The selected candidates were thereafter applied in photovoltaic devices, demonstrating power conversion efficiency (PCE) up to 21.5% for B18C6. The capacity to capture Pb was evidenced by the time-of-flight secondary ion mass spectrometry (ToF-SIMS) analysis, complemented by ultraviolet photoelectron spectroscopy (UPS), time-resolved photoluminescence (TRPL), and transient absorption spectroscopy (TAS) to confirm that the use of crown ether affects interfacial energetics and suppresses non-radiative recombination. The resulting solar cells maintained their performance without significant efficiency loss at 85% humidity for 300 h.
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2021R1F1A1047203 and 2022R1F1A1066078). Author RKC is thankful to the NRF grant funded by the Korea government (MSIT) (2021R1I1A1A01061036). H.C. acknowledges financial support from NRF grant funded by the Korea government (MSIT) (RS-2023- 00213920).