Spontaneous formation of robust two-dimensional perovskite phases
- Shaun Tan
- Meng-Chen Shih
- Yongli Lu
- Seung-Gu Choi
- Yifan Dong
- Joo-Hong Lee
- Ilhan Yavuz
- Bryon W. Larson
- So Yeon Park
- Tim Kodalle
- Ruiqi Zhang
- Matthias J. Grotevent
- Yu-Kuan Lin
- Hua Zhu
- Vladimir Bulović
- Carolin M. Sutter-Fella
- Nam-Gyu Park
- Matthew C. Beard
- Jin-Wook Lee
- Kai Zhu
- Moungi G. Bawendi
2025-05-22
The two-dimensional on three-dimensional (2D/3D) perovskite bilayer heterostructure can improve the stability and performance of perovskite solar cells. We show that the 2D/3D perovskite stack in a device evolves dynamically during its end-of-life decomposition. Initially phase-pure 2D interlayers can evolve differently, resulting in different device stabilities. We show that a robust 2D interlayer can be formed using mixed solvents to regulate its crystallinity and phase purity. The resulting 2D/3D devices achieved 25.9% efficiency and had good durability, retaining 91% of their initial performance after 1074 hours at 85°C using maximum power point tracking.