Upscaling efficient and stable perovskite layers is one of the most challenging issues in the commercialization of perovskite solar cells. Here, a lead halide–templated crystallization strategy is developed for printing formamidinium (FA)–cesium (Cs) lead triiodide perovskite films. High-quality large-area films are achieved through controlled nucleation and growth of a lead halide•N-methyl-2-pyrrolidone adduct that can react in situ with embedded FAI/CsI to directly form α-phase perovskite, sidestepping the phase transformation from δ-phase. A nonencapsulated device with 23% efficiency and excellent long-term thermal stability (at 85°C) in ambient air (~80% efficiency retention after 500 hours) is achieved with further addition of potassium hexafluorophosphate. The slot die–printed minimodules achieve champion efficiencies of 20.42% (certified efficiency 19.3%) and 19.54% with an active area of 17.1 and 65.0 square centimeters, respectively.

升级高效且稳定的钙钛矿层是钙钛矿太阳能电池商业化中最具挑战性的问题之一。在这里，开发了一种以卤化铅为模板的结晶策略，用于印刷甲脒（FA）-铯（Cs）三碘化铅钙钛矿薄膜。通过控制卤化铅的成核和生长获得高质量的大面积薄膜• N-甲基-2-吡咯烷酮加合物，可与嵌入的 FAI/CsI 原位反应，直接形成 α 相钙钛矿，避开 δ 相的相变。通过进一步添加六氟磷酸钾，可实现在环境空气中具有 23% 效率和出色长期热稳定性（85°C）（500 小时后效率保持率约为 80%）的非封装器件。槽模印刷微型模块的效率分别为 20.42%（认证效率 19.3%）和 19.54%，有效面积分别为 17.1 和 65.0 平方厘米。