Inhibiting defect passivation failure in perovskite for perovskite/Cu(In,Ga)Se₂ monolithic tandem solar cells with certified efficiency 27.35%

TY - JOUR

T1 - Inhibiting defect passivation failure in perovskite for perovskite/Cu(In,Ga)Se2 monolithic tandem solar cells with certified efficiency 27.35%

AU - Pei, Fengtao

AU - Lin, Shuping

AU - Zhang, Zhongyang

AU - Lin, Shiju

AU - Huang, Xingye

AU - Zhao, Ming

AU - Xu, Jian

AU - Zhuang, Xinmeng

AU - Zhang, Ying

AU - Tang, Jiahong

AU - Chen, Yanrun

AU - Li, Kailin

AU - Wang, Lan

AU - Liu, Guilin

AU - Qian, Dongmin

AU - Liu, Huifeng

AU - Zhou, Wentao

AU - Chen, Yihua

AU - Wang, Jianpu

AU - Zhou, Huanping

AU - Li, Boyan

AU - Zhong, Dalong

AU - Jiang, Yan

AU - Chen, Qi

N1 - Publisher Copyright: © The Author(s), under exclusive licence to Springer Nature Limited 2025.

PY - 2025/7

Y1 - 2025/7

N2 - Thin-film tandem solar cells with wide-bandgap perovskites and Cu(In,Ga)Se2 hold promise for cost-effective lightweight photovoltaics. However, the power conversion efficiency and stability of perovskite/Cu(In,Ga)Se2 tandem solar cells are not yet comparable to single-junction counterparts due to recombination losses and photothermal-induced degradation in wide-bandgap perovskites. In this study, we show that common strategies for perovskite passivation often fail under combined thermal and illumination stresses due to the passivator desorption. We demonstrate a robust passivator with deliberately designed functional groups that inhibits passivator desorption regardless of perovskite surface termination, enhances resistance to photothermal stresses and substantially suppresses phase segregation. The wide-bandgap perovskite solar cells achieved a champion power conversion efficiency of 23.5% with negligible degradation after 1,000 hours of continuous operation under 1-sun illumination at approximately 50 °C. When integrated into perovskite/Cu(In,Ga)Se2 tandem cells, they achieved the steady state power conversion efficiency of 27.93% (certified 27.35%), with stable operation for over 420 hours at ~38 °C in ambient air.

AB - Thin-film tandem solar cells with wide-bandgap perovskites and Cu(In,Ga)Se2 hold promise for cost-effective lightweight photovoltaics. However, the power conversion efficiency and stability of perovskite/Cu(In,Ga)Se2 tandem solar cells are not yet comparable to single-junction counterparts due to recombination losses and photothermal-induced degradation in wide-bandgap perovskites. In this study, we show that common strategies for perovskite passivation often fail under combined thermal and illumination stresses due to the passivator desorption. We demonstrate a robust passivator with deliberately designed functional groups that inhibits passivator desorption regardless of perovskite surface termination, enhances resistance to photothermal stresses and substantially suppresses phase segregation. The wide-bandgap perovskite solar cells achieved a champion power conversion efficiency of 23.5% with negligible degradation after 1,000 hours of continuous operation under 1-sun illumination at approximately 50 °C. When integrated into perovskite/Cu(In,Ga)Se2 tandem cells, they achieved the steady state power conversion efficiency of 27.93% (certified 27.35%), with stable operation for over 420 hours at ~38 °C in ambient air.

UR - https://www.scopus.com/pages/publications/105009477226

U2 - 10.1038/s41560-025-01761-5

DO - 10.1038/s41560-025-01761-5

M3 - Article

AN - SCOPUS:105009477226

SN - 2058-7546

VL - 10

SP - 824

EP - 835

JO - Nature Energy

JF - Nature Energy

IS - 7

ER -