Tin‐based perovskites are more environmentally friendly than their lead‐based alternatives. Perovskite light‐emitting diodes (PeLEDs) using iodide‐based tin perovskites have achieved considerable advancements in efficiency. However, PeLEDs using bromide‐based tin perovskites have not progressed as rapidly, primarily due to challenges in controlling their crystallization processes. Here, an interfacial reaction‐assisted crystallization method is introduced to achieve bright and efficient CsSnBr3 PeLEDs. It is started by forming an intermediate phase through the coordination of SnBr2 with ethylenediamine derivatives. Subsequently, a protonation reaction is designed between the intermediate phase and the acidic polyethylenedioxythiophene: poly(styrene sulfonate) hole‐transport layer to generate high‐quality CsSnBr3 films. Additionally, the use of potassium thiocyanate additives effectively enhances the photoluminescence efficiency of the CsSnBr3 films. These efforts result in CsSnBr3‐based PeLEDs achieving a maximum luminance of 787 cd m−2 and a peak external quantum efficiency of 0.91%, demonstrating the most efficient and brightest CsSnBr3‐based PeLEDs to date. This work opens an avenue to better control the crystallization of tin‐based perovskite.

中文翻译：

---

通过界面反应辅助结晶实现明亮高效的 CsSnBr3 发光二极管


锡基钙钛矿比其铅基替代品更环保。使用碘基锡钙钛矿的钙钛矿发光二极管 （PeLED） 在效率方面取得了相当大的进步。然而，使用溴化物基锡钙钛矿的 PeLED 进展并不迅速，这主要是由于控制其结晶过程的挑战。在这里，引入了一种界面反应辅助结晶方法，以获得明亮高效的 CsSnBr3 PeLED。它是通过 SnBr2 与乙二胺衍生物配位形成中间相开始的。随后，在中间相和酸性聚乙烯二氧噻吩之间设计质子化反应：聚（苯乙烯磺酸盐）空穴传输层，以生成高质量的 CsSnBr3 薄膜。此外，硫氰酸钾添加剂的使用有效地提高了 CsSnBr3 薄膜的光致发光效率。这些努力导致基于 CsSnBr3 的 PeLED 实现了 787 cd m-2 的最大亮度和 0.91% 的峰值外部量子效率，展示了迄今为止最高效、最亮的基于 CsSnBr3 的 PeLED。这项工作为更好地控制锡基钙钛矿的结晶开辟了一条途径。