In this study, a facile passivation for methylammonium lead bromide (MAPbBr₃) single crystals is reported. Stability against moisture and light remains the most critical demerit of perovskite materials, which is improved by depositing a 40 Å thick hydrophobic copper phthalocyanine (CuPc) layer on top of the cleaved perovskite surface. The water and light exposure processes were monitored with X-ray photoelectron spectroscopy with precise control of the exposure time and pressure. It is found that the CuPc top layer could protect the sample from moisture infiltration at a water exposure of 10¹³ L, while the nonpassivated sample started to degrade at 10⁸ L. During the light exposure, CuPc also slowed down the light-induced degradation, which is supported by the elemental ratio change of metallic lead and bromine. These results are further confirmed by the morphological comparison via scanning electron microscopy and focused ion beam.

中文翻译：

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MAPbBr3 单晶表面的 CuPc 钝化

_{在这项研究中，报道了甲基铵溴化铅（MAPbBr 3}）单晶的轻松钝化。对湿气和光的稳定性仍然是钙钛矿材料最关键的缺点，通过在劈裂的钙钛矿表面上沉积 40 Å 厚的疏水性铜酞菁 (CuPc) 层可以改善这一缺点。使用 X 射线光电子能谱监测水和光的暴露过程，并精确控制暴露时间和压力。结果发现，在 10 ^{13 L 的水暴露条件下，CuPc 顶层可以保护样品免受水分渗透，而未钝化的样品在 10 8} L 的水暴露条件下开始降解。在光照过程中，CuPc 还减缓了光诱导的降解。 ，这是由金属铅和溴的元素比例变化所支持的。通过扫描电子显微镜和聚焦离子束的形态比较进一步证实了这些结果。