Interface engineering has been extensively used in perovskite light-emitting diodes (PeLEDs), which proves to be an effective and intelligent approach for surface defect passivation. However, the existing passivation strategy is restricted to the solution process, which results in poor compatibility with vapor-deposited PeLEDs and moderate controllability. Here, we propose a dual-interface modification strategy to facilitate the performance improvement of vapor-deposited all-inorganic red PeLEDs. An ultrathin phenylethanamine bromide (PEABr) layer is introduced to both the upper and lower interfaces of the vapor-deposited perovskite emission layer by vapor deposition. The vapor deposition of the PEABr with fine-controlled film thickness is a reliable and simple process and compatible with vapor-deposited all-inorganic PeLEDs. The dual-interface modification plays an observable role in manipulating the crystallization and surface morphology of the CsPbBrI₂ film, which is of significance for the improvement of the PeLEDs’ performance. As a result, the red PeLEDs achieve a maximum luminance and external quantum efficiency of 2338 cd/m² and 1.75%, corresponding to enhancements of 2.75 and 5.25 times compared with those of PeLEDs without PEABr. This approach paves the way to high-efficiency all-evaporated all-inorganic PeLEDs.

中文翻译：

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气相沉积双界面改性钙钛矿高效全无机红色钙钛矿发光二极管

界面工程已广泛应用于钙钛矿发光二极管 (PeLED)，被证明是一种有效且智能的表面缺陷钝化方法。然而，现有的钝化策略仅限于溶液工艺，导致与气相沉积PELED的兼容性较差，可控性中等。在这里，我们提出了一种双界面改性策略，以促进气相沉积全无机红色 PeLED 的性能改进。通过气相沉积将超薄苯乙胺溴化物 (PEABr) 层引入到气相沉积钙钛矿发射层的上下界面。具有精细控制膜厚度的 PEABr 的气相沉积是一种可靠且简单的过程，并且与气相沉积的全无机 PeLED 兼容。₂薄膜，这对于提高 PeLED 的性能具有重要意义。因此，红色 PeLED 的最大亮度和外部量子效率分别为 2338 cd/m ²和 1.75%，与不含 PEABr 的 PeLED 相比，增强了 2.75 倍和 5.25 倍。这种方法为高效全蒸发全无机 PeLED 铺平了道路。