Dubey Charu, Yadav Anjana, Kachhap Santosh, Singh Sunil Kumar, Gupta Govind, Singh Satendra Pal, Singh Akhilesh Kumar
Department of Physical Sciences, Banasthali Vidyapith, Banasthali, Rajasthan 304022, India.
Department of Physics, Indian Institute of Technology (Banaras Hindu University) Varanasi 221005, India.
Methods Appl Fluoresc. 2024 Aug 21;12(4). doi: 10.1088/2050-6120/ad6ca1.
Cesium lead halide perovskite (CsPbX; X = Cl, Br, I) nanocrystals showing intense band-edge emission and high photoluminescence quantum yield are known to be a potential candidate for application in optoelectronic devices. However, controlling toxicity due to the presence of Pbin lead-based halide perovskites is a major challenge for the environment that needs to be tackled cautiously. In this work, we have partially replaced Pbwith Mnions in the CsPb(Cl/Br)nanocrystals and investigated their impact on the structural and optical properties. The Rietveld refinement shows that CsPbClBr nanocrystals possess a cubic crystal structure with3̅space group, the Mndoping results in the contraction of the unit cell. The CsPb(Cl/Br): Mn nanocrystals show a substantial change in the optical properties with an additional emission band at ∼588 nm through a d-d transition, changing the emission color from blue to pink. Here, a didodecyldimethylammonium bromide (DDAB) ligand that triggers both anion and ligand exchange in the CsPb(Cl/Br): Mn nanocrystals have been used to regulate the exchange reaction and tune the emission color of halide perovskites by changing the peak position and the PL intensities of band-edge and Mndefect states. We have also shown that oleic acid helps in the desorption of oleylamine capping from the CsPb(Cl/Br): Mn nanocrystal surfaces and DDAB, resulting in the substitution of Clwith Bras well as provides capping with shorter branched length ligand which led to increase in the overall PL intensity by many folds.
卤化铯铅钙钛矿（CsPbX；X = Cl、Br、I）纳米晶体具有强烈的带边发射和高光致发光量子产率，是光电器件应用的潜在候选材料。然而，由于铅基卤化钙钛矿中存在铅而控制其毒性是一个需要谨慎应对的重大环境挑战。在这项工作中，我们在CsPb(Cl/Br)纳米晶体中用锰离子部分替代了铅离子，并研究了它们对结构和光学性质的影响。Rietveld精修表明，CsPbClBr纳米晶体具有立方晶体结构，空间群为(3̅)，锰掺杂导致晶胞收缩。CsPb(Cl/Br):Mn纳米晶体的光学性质发生了显著变化，通过d-d跃迁在约588 nm处出现了一个额外的发射带，发射颜色从蓝色变为粉色。在这里，一种能引发CsPb(Cl/Br):Mn纳米晶体中阴离子和配体交换的二癸基二甲基溴化铵（DDAB）配体被用于调节交换反应，并通过改变带边和Mn缺陷态的峰值位置和PL强度来调整卤化钙钛矿的发射颜色。我们还表明，油酸有助于从CsPb(Cl/Br):Mn纳米晶体表面解吸油胺封端和DDAB，导致Cl被Br取代，并提供较短支链长度配体的封端，从而使整体PL强度提高了许多倍。
