Grain Boundary Elimination via Recrystallization‐Assisted Vapor Deposition for Efficient and Stable Perovskite Solar Cells and Modules

• Published in: Advanced materials (Weinheim) Vol. 35; no. 44; pp. e2304625 - n/a
• Main Authors: Wang, Yulong, Lv, Pin, Pan, Junye, Chen, Jiahui, Liu, Xinjie, Hu, Min, Wan, Li, Cao, Kun, Liu, Baoshun, Ku, Zhiliang, Cheng, Yi‐Bing, Lu, Jianfeng
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.11.2023
• Subjects: Crystal defects; Crystallization; Current carriers; Grain boundaries; Mass production; Materials science; Modules; perovskite solar cells; Perovskites; Photovoltaic cells; Recombination reactions; Recrystallization; Solar cells; stability; Temperature dependence; Vapor deposition; Vapors; recrystallization; modules; perovskite solar cells; stability; vapor deposition
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202304625

Vapor deposition is a promising technology for the mass production of perovskite solar cells. However, the efficiencies of solar cells and modules based on vapor‐deposited perovskites are significantly lower than those fabricated using the solution method. Emerging evidence suggests that large defects are generated during vapor deposition owing to a specific top‐down crystallization mechanism. Herein, a hybrid vapor deposition method combined with solvent‐assisted recrystallization for fabricating high‐quality large‐area perovskite films with low defect densities is presented. It is demonstrated that an intermediate phase can be formed at the grain boundaries, which induces the secondary growth of small grains into large ones. Consequently, perovskite films with substantially reduced grain boundaries and defect densities are fabricated. Results of temperature‐dependent charge‐carrier dynamics show that the proposed method successfully suppresses all recombination reactions. Champion efficiencies of 21.9% for small‐area (0.16 cm2) cells and 19.9% for large‐area (10.0 cm2) solar modules under AM 1.5 G irradiation are achieved. Moreover, the modules exhibit high operational stability, i.e., they retain >92% of their initial efficiencies after 200 h of continuous operation. A vapor deposition method in combination with a solvent‐assisted recrystallization technique is presented to fabricate high‐quality larger‐area perovskite film. Efficiency of 19.9% is achieved, which is among the highest values ever reported for minimodules based on vapor‐deposited perovskite.