Selective Crystallization Delay in Wide-Bandgap Perovskites Enables Initial Homogeneous Phase for Square Centimeter Perovskite/Organic Tandem Solar Cells
Jialei Zheng1, Weijie Chen1（陈炜杰）, Ziyue Wang1, Shuaiqing Kang1, Pengpeng Dong1, Yue Yin1, Haiyang Chen1, Jianlei Cao1, Jixiang Yuan1, Guiying Xu1, Jiacheng Xu1, Yaowen Li1,2（李耀文）*
1Laboratory of Advanced Optoelectronic Materials, Suzhou Key Laboratory of Novel Semiconductor-optoelectronics Materials and Devices, State Key Laboratory of Bioinspired Interfacial Materials Science, College of Chemistry, Chemical Engineering and Materials Science Soochow University Suzhou 215123, China
2Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University Suzhou 215123, China
Adv. Mater. 2025, 37, e10437
Abstract: Mixed halide wide-bandgap (WBG) perovskites, used in high-performance perovskite/organic tandem solar cells (TSCs), are prone to phase segregation under light irradiation. Particularly, the initial inhomogeneous halide phase distribution in WBG perovskites can accelerate the phase segregation under operational stressors, thus hindering scaling of TSCs that require high phase homogeneity. Here, a selective delayed crystallization strategy is proposed in which a functional agent (3-amino-5-fluorobenzamide; AFBA) is used to regulate the initial halide phase distribution. The -NH2 of AFBA, with a low electron-cloud density, shows a higher binding affinity with bromide than with iodide, thus selectively delaying the rapid crystallization of bromide; this phenomenon induces a homogeneous halide distribution across the film. The initial homogeneous film is phase-stable under operational stressors. As a result, the square-centimeter WBG perovskite front cell achieves a high efficiency of 18.61%. When stacked with organic subcells, the square-centimeter perovskite/organic TSC exhibits a remarkable efficiency of 25.21%, showing a weak-dependence of efficiency on size from 0.062 to 2.000 cm2, as well as a prolonged operational lifetime with a T90 of 1500 h. Perovskite/organic TSCs are also connected in series with electrochromic devices to dynamically monitor the TSC performance via the color variation, providing insights for their future applications.
Article information: https://doi.org/10.1002/adma.202510437
