Tin halide perovskites are promising for optoelectronics, although their sensitivity to ambient conditions due to Sn(II) oxidation presents a challenge. Encapsulation techniques can mitigate degradation and facilitate advanced studies of the intrinsic properties. To study and improve the ambient stability of CsSnBr₃ and CsSnI₃ nanocrystal (NC) thin films, we explored various encapsulation methods: organic, inorganic, and hybrid. We employed three methods for organic encapsulation: co-deposition with NCs, co-deposition with an additional top layer, and in situ polymerization with NCs. We synthesized thin layers of alumina by using atomic layer deposition for inorganic encapsulation. While individual methods offered marginal improvements, the hybrid approach provided the best results. By employing a hybrid heterostructured thin-film strategy, with the NC layer covered by a thin layer of poly(methyl methacrylate) followed by a 40 nm alumina layer, the stability in air was improved from a few seconds to a record period of 15 days, a crucial advancement for the further exploration of tin halide perovskites.

中文翻译：

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通过聚合物和 Al2O3 封装制备卤化锡钙钛矿纳米晶的空气稳定薄膜


卤化锡钙钛矿在光电子学中的应用前景广阔，尽管由于 Sn（II） 氧化，它们对环境条件的敏感性带来了挑战。封装技术可以减轻降解并促进对内在特性的高级研究。为了研究和提高 CsSnBr₃ 和 CsSnI₃ 纳米晶 （NC） 薄膜的环境稳定性，我们探索了各种封装方法：有机、无机和杂化。我们采用了三种有机封装方法：与 NC 共沉积、与附加顶层共沉积以及与 NC 的原位聚合。我们通过使用原子层沉积进行无机封装合成了氧化铝薄层。虽然个别方法提供了边际改善，但混合方法提供了最好的结果。通过采用混合异质结构薄膜策略，NC 层覆盖一层聚甲基丙烯酸甲酯薄层，然后是 40 nm 氧化铝层，在空气中的稳定性从几秒钟提高到创纪录的 15 天，这是进一步勘探卤化锡钙钛矿的重要进步。