In recent years, significant attention has been paid to perovskite materials. In particular, lead triiodide-based perovskites have exhibited superb optoelectronic properties. Enhancing the stability of these materials is an essential step towards large-scale applications. In this study, by simply adding trioctylphosphine (TOP) as part of the post-synthesis treatment, we significantly enhance the stability of CsPbI₃ quantum dots (QDs) in the solution phase, which otherwise decay rapidly in hours. For CsPbI₃ QDs treated with TOP, the absorption and photoluminescence emission properties are unchanged over the course of weeks, and the quantum yield remains almost constant at 30% even after 1 month. The morphologies of both treated and untreated QDs are initially cubic; however, the treated QDs largely maintain their initial size and shape, while the untreated ones lose size uniformity, which is a sign of degradation. Infrared spectroscopy and X-ray photoelectron spectroscopy confirm the presence of P in the TOP-treated QDs. We insights that help to resolve the intrinsic instability issue of triiodide perovskite materials and devices.

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近年来，对钙钛矿材料已给予了极大的关注。特别地，基于三碘化铅的钙钛矿具有优异的光电性能。增强这些材料的稳定性是迈向大规模应用的必不可少的一步。在这项研究中，通过简单地添加三辛基膦（TOP）作为合成后处理的一部分，我们显着增强了溶液相中CsPbI ₃量子点（QDs）的稳定性，否则它会在数小时内迅速衰减。对于CsPbI ₃经过TOP处理的量子点，其吸收和光致发光发射特性在几周内没有变化，即使在1个月后，量子产率也几乎保持恒定在30％。经处理和未经处理的量子点的形态最初都是立方的。但是，经过处理的量子点在很大程度上保持了其初始大小和形状，而未经处理的量子点则失去了大小均匀性，这是性能下降的迹象。红外光谱和X射线光电子能谱证实了TOP处理的量子点中存在P。我们的见解有助于解决三碘化物钙钛矿材料和装置的内在不稳定性问题。

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