School of Nano Science and Technology, Indian Institute of Technology Kharagpur, 721302, Kharagpur, India.
Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Nam-gu, 37673, Pohang, Republic of Korea.
Angew Chem Int Ed Engl. 2023 May 22;62(22):e202302852. doi: 10.1002/anie.202302852. Epub 2023 Apr 25.
Although α-CsPbI is regarded as an attractive optical luminophore, it is readily degraded to the optically inactive δ-phase under ambient conditions. Here, we present a simple approach to revive degraded ("optically sick") α-CsPbI through "medication" with thiol-containing ligands. The effect of different types of thiols is systematically studied through optical spectroscopy. The structural reconstruction of degraded α-CsPbI nanocrystals to cubic crystals in the presence of thiol-containing ligands is visualized through high-resolution transmission electron microscopy and supported by X-ray diffraction analysis. We found that 1-dodecanethiol (DSH) effectively revives degraded CsPbI and results in high immunity towards moisture and oxygen, hitherto unreported. DSH facilitates the passivation of surface defects and etching of degraded Cs PbI phase, thus reverting them back to the cubic CsPbI phase, leading to enhanced PL and environmental stability.
虽然α-CsPbI 被认为是一种有吸引力的光学发光体，但它在环境条件下很容易降解为非活性的 δ 相。在这里，我们提出了一种简单的方法，通过含有巯基的配体“药物治疗”来恢复降解的（“病态”）α-CsPbI。通过光学光谱系统地研究了不同类型的硫醇的效果。通过高分辨率透射电子显微镜观察到在含有巯基的配体存在下，降解的α-CsPbI 纳米晶体的结构重构为立方晶体，并通过 X 射线衍射分析得到证实。我们发现，1-十二硫醇（DSH）有效地恢复了降解的 CsPbI，并对水分和氧气具有高的免疫力，这是以前未曾报道过的。DSH 促进了表面缺陷的钝化和降解的 CsPbI 相的刻蚀，从而使它们返回到立方 CsPbI 相，导致增强的 PL 和环境稳定性。
