Shin, Yun SeopSong, Ji WonLee, Dong GyuLee, JaehwiSeo, JongdeukRoe, JinaShin, Gwang YongKim, DongshinYeop, JiwooLee, DongminKim, MinjinJo, YimhyunJang, HyungsuSon, Jung GeonLee, WoojinSon, JeongminPark, SujungCho, ShinukShin, Tae JooKim, Gi HwanKim, Jin YoungLee, Tae KyungGrätzel, MichaelKim, Dong Suk2025-01-252025-01-252025-01-252025-01-1510.1016/j.joule.2024.10.0112-s2.0-85210742700https://infoscience.epfl.ch/handle/20.500.14299/244393In conventional n-i-p perovskite solar cells, unsolved issues persist, particularly concerning notorious performance degradation under prolonged heat exposure at 85°C. By reducing the concentration of 4-tert-butylpyridine (tBP) and lithium bis(trifluoromethanesulfonyl)imide and adjusting their molar ratio to one, we achieved a dramatic increase in the heat stability of the PSC while boosting its power conversion efficiency (PCE). The formation of a 1:1 Li+-tBP complex was crucial for preventing free tBP molecules in the hole-transporting layer (HTL), suppressing the de-doping of the p-type HTL by tBP and the release of tBP vapor under heat stress. Consequently, the PSCs accomplished a PCE of 26.18% (certified 26.00%) while demonstrating remarkable resilience to heat exposure at 85°C due to the raised glass transition temperature of the HTL. Furthermore, a perovskite solar mini-module with an aperture area of 25 cm2 achieved a PCE of 23.29%, highlighting their potential for commercial PSC deployment.false4-tert-butylpyridineconventional perovskite solar cellde-doping controldopant engineeringheat-stablehole-transporting layerperovskite solar modulespiro-OMeTADtext::journal::journal article::research article