Organic‐inorganic halide perovskite materials have become a shining star in the photovoltaic field due to their unique properties, such as high absorption coefficient, optimal bandgap, and high defect tolerance, which also lead to the breathtaking increase in power conversion efficiency from 3.8% to over 22% in just seven years. Although the highest efficiency was obtained from the TiO₂ mesoporous structure, there are increasing studies focusing on the planar structure device due to its processibility for large‐scale production. In particular, the planar p‐i‐n structure has attracted increasing attention on account of its tremendous advantages in, among other things, eliminating hysteresis alongside a competitive certified efficiency of over 20%. Crucial for the device performance enhancement has been the interface engineering for the past few years, especially for such planar p‐i‐n devices. The interface engineering aims to optimize device properties, such as charge transfer, defect passivation, band alignment, etc. Herein, recent progress on the interface engineering of planar p‐i‐n structure devices is reviewed. This review is mainly focused on the interface design between each layer in p‐i‐n structure devices, as well as grain boundaries, which are the interfaces between polycrystalline perovskite domains. Promising research directions are also suggested for further improvements.

中文翻译：

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高效稳定的平面p-i-n钙钛矿太阳能电池的接口工程

有机-无机卤化物钙钛矿材料因其独特的特性（例如高吸收系数，最佳带隙和高缺陷耐受性）而成为光伏领域的一颗璀璨明星，这也使功率转换效率从3.8％惊人地提高到在短短7年内超过22％尽管从TiO ₂获得了最高的效率介孔结构，由于其可大规模生产的可加工性，越来越多的研究集中在平面结构器件上。尤其是，平面PIN结构由于其巨大的优势而引起了越来越多的关注，尤其是它消除了磁滞现象，同时获得了超过20％的竞争性经认证的效率。过去几年来，接口性能一直是提高设备性能的关键，特别是对于这种平面p-i-n设备。接口工程旨在优化器件性能，例如电荷转移，缺陷钝化，能带对准等。在此，对平面p-i-n结构器件接口工程的最新进展进行了综述。本文主要关注p-i-n结构设备各层之间的接口设计，以及晶界，这是多晶钙钛矿域之间的界面。还提出了有希望的研究方向，以进行进一步的改进。