Oriented Growth for Efficient and Scalable Perovskite Solar Cells by Vapor–Solid Reaction

• Published in: Advanced functional materials Vol. 34; no. 21
• Main Authors: Duan, Changyu, Zhong, Jialing, Hu, Shenghan, Dou, Yichen, Lu, Jianfeng, Cheng, Yi‐Bing, Ku, Zhiliang
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.05.2024
• Subjects: Carrier density; Crystal structure; large‐area; oriented growth; perovskite solar cells; Perovskites; photoelectric anisotropy; Photovoltaic cells; Preferred orientation; Solar cells; vapor deposition; Vapors
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202313435

The precise control and understanding of crystal orientation in perovskite polycrystalline films are crucial for the development of efficient and stable devices. However, achieving this control remains a significant challenge. Herein, a PbI2 oriented growth strategy is developed, combined with in situ vapor–solid reaction transformations, to achieve oriented growth of full‐vacuum perovskite films. Grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) analysis revealed the general pattern of PbI2 oriented vapor growth and in situ vapor–solid reaction transformation in this two‐step process. The resulting preferred orientation has effectively reduced trap state density, optimizing the carrier dynamics. As a result, champion efficiencies of 22.11% (0.148 cm2), 20.60% (1 cm2), and 19.41% (5 × 5 cm2 mini‐modules) are achieved, which are the highest value for perovskite based on vapor–solid reaction. Additionally, the oriented growth method is applicable to a variety of guide layers and is extended to 30 × 30 cm2 film, demonstrating the universality and scalability of the method. Crystal orientation is reported to affect the optoelectronic properties of perovskite films. Here, the orientation control of vapor‐deposited perovskites is achieved by the oriented growth of the PbI2 precursor, and the mechanism is investigated by the Grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) technique. Further, as a full vapor‐phase process, this method has been successfully extended to the fabrication of large‐area perovskite films and devices.