Abstract In this paper, we designed Eu2+-doped BaAlF5 and BaSiF6 downconversion nanophosphors with strong f-f transition emission to realize the quantitative detection of TNP. The surface of the as-prepared nanophosphors was modified by polyethylenimine (PEI) to increase the water solubility and to provide a pair of electrons to bind to the benzene ring in TNP, forming a Meisenheimer complex. The detection principle of TNP is based on luminescence resonance energy transfer (LRET) technology, where the PEI-functionalized BaAlF5:Eu2+ and BaSiF6:Eu2+ nanophosphors are used as energy donors and TNP is an energy acceptor. With increasing TNP concentrations, the luminescence intensity of the BaAlF5:Eu2+ and BaSiF6:Eu2+ nanophosphors at 359 nm [4f7(6P7/2)→4f7(8S7/2) transition of Eu2+] displayed dramatic luminescent quenching. The BaAlF5:Eu2+@PEI or BaSiF6:Eu2+@PEI nanophosphor downconversion luminescent sensors show great sensitivity and selectivity and good linearity, and the detection limits of TNP were 0.57 and 2.82 ng/mL, respectively.

中文翻译：

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基于 Eu2+ 的 ff 跃迁检测 2,4,6-三硝基苯酚

摘要 本文设计了具有强ff跃迁发射的Eu2+掺杂BaAlF5和BaSiF6下转换纳米荧光粉，实现了TNP的定量检测。所制备的纳米磷光体的表面被聚乙烯亚胺（PEI）改性，以增加水溶性并提供一对电子与 TNP 中的苯环结合，形成迈森海默复合物。TNP 的检测原理基于发光共振能量转移 (LRET) 技术，其中 PEI 功能化的 BaAlF5:Eu2+ 和 BaSiF6:Eu2+ 纳米磷光体用作能量供体，TNP 是能量受体。随着 TNP 浓度的增加，BaAlF5:Eu2+ 和 BaSiF6:Eu2+ 纳米磷光体在 359 nm [Eu2+ 的 4f7(6P7/2)→4f7(8S7/2) 跃迁] 处的发光强度显示出显着的发光猝灭。BaAlF5：