发光学报, 2019, 40 (10): 1220, 网络出版: 2019-10-23
Ni掺杂提高紫光CsPbCl3钙钛矿纳米晶的发光热稳定性
Improving Thermal Stability of Photoluminescence in Violet-emitting CsPbCl3 Perovskite Nanocrystals Using Ni Doping
摘要
为了提高紫光CsPbCl3纳米晶的发光热稳定性,研究了不同掺杂浓度的Ni离子对CsPbCl3纳米晶的结构和发光性质的影响。通过改变Ni/Pb进料量比,在190 ℃温度下制备出不同浓度Ni掺杂的CsPbCl3 (Ni∶CsPbCl3)纳米晶。发现随着Ni/Pb进料量比的增加,Ni∶CsPbCl3纳米晶的405 nm发光量子效率得到了较大的提高,高达54%,但当Ni/Pb进料比超过4∶1之后,Ni∶CsPbCl3纳米晶的发光量子效率开始下降,这是由于氯化镍的浓度过高,影响了CsPbCl3纳米晶的成核和生长过程。还观察到,随着Ni/Pb进料比的增加,Ni∶CsPbCl3纳米晶的平均尺寸逐渐减小,晶格变得更加有序。通过对不同浓度的Ni∶CsPbCl3纳米晶的变温光谱测量,发现Ni离子明显地减少CsPbCl3纳米晶的发光热猝灭,有效地改善了其发光热稳定性。实验结果表明,Ni离子掺杂有效地提高了紫光CsPbCl3纳米晶的发光效率,可能归因于Ni离子掺杂减少了CsPbCl3纳米晶中的缺陷。
Abstract
In order to effectively improve the thermal stability of luminescence in violet-emitting CsPbCl3 perovskite nanocrystals(NCs), the effects of various Ni doping concentrations on their structural and luminescent properties were studied. The Ni doped CsPbCl3 (Ni∶CsPbCl3) NCs with various Ni doping concentrations were synthesized at 190 ℃ by varying the feed Ni/Pb molar ratio. It was found that the quantum yield of 405 nm photoluminescence band in Ni∶CsPbCl3 NCs was significantly improved up to 54% with increasing the Ni/Pb feed molar ratio while it started to drop after the molar ratio was higher than 4∶1. This is because the nucleation and growth processes of the NCs were influenced in the presence of high concentration NiCl2. In addition, it was observed that the average sizes of Ni∶CsPbCl3 NCs were reduced with increasing Ni/Pb molar ratio. The temperature-dependent photoluminescence spectra demonstrated that the Ni doping really reduced thermal quenching of photoluminescence in Ni∶CsPbCl3 NCs and greatly enhanced their thermal stability. The experimental results indicated that the enhancement mechanism of luminescence in violet-emitting Ni∶CsPbCl3 NCs was attributed to reduction of defects in NCs with Ni doping.
陈肖慧, 邢珂, 曹震, 袁曦, 赵家龙. Ni掺杂提高紫光CsPbCl3钙钛矿纳米晶的发光热稳定性[J]. 发光学报, 2019, 40(10): 1220. CHEN Xiao-hui, XING Ke, CAO Zhen, YUAN Xi, ZHAO Jia-long. Improving Thermal Stability of Photoluminescence in Violet-emitting CsPbCl3 Perovskite Nanocrystals Using Ni Doping[J]. Chinese Journal of Luminescence, 2019, 40(10): 1220.