School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
School of Chemistry and Chemical Engineering, Nantong University, Nantong 226019, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Apr 15;231:118131. doi: 10.1016/j.saa.2020.118131. Epub 2020 Feb 6.
A novel method for turn-off sensing 1,1-diamino-2,2-dinitroethylene (FOX-7) in aqueous medium was first proposed based on the inner filter effect (IFE) of FOX-7 on the fluorescence of molybdenum disulfide quantum dots (MoS QDs). Water-soluble MoS QDs as the fluorophore were prepared by the simple hydrothermal method. The morphology, structure, composition and optical properties of the prepared MoS QDs were characterized by Transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), UV-vis absorption and photoluminescence spectra. The results showed that the MoS QDs had good water dispersibility and emitted strong photoluminescence with a particle size of 2 nm. Under the optimal experimental conditions, the fluorescence signal of MoS QDs was quenched in the concentrations range of FOX-7 (0.5-100 μM) and the limit of detection (LOD) of the sensor was 0.19 μM. The method had been applied to analyze the real water samples with good selectivity and stability. Moreover, the quenching mechanism was studied systematically by the Fourier transform infrared (FT-IR), UV-vis absorption spectra, fluorescence lifetime, and Stern-Volmer equation, which had been proved to be static quenching. The fluorescence quenching mechanism is mainly IFE and electron transfer.
首次提出了一种在水介质中关闭感应 1,1-二氨基-2,2-二硝基乙烯（FOX-7）的新方法，该方法基于 FOX-7 对二硫化钼量子点（MoS QDs）荧光的内滤效应（IFE）。水溶性 MoS QDs 作为荧光团，通过简单的水热法制备。通过透射电子显微镜（TEM）、傅里叶变换红外（FT-IR）、X 射线光电子能谱（XPS）、紫外-可见吸收光谱和光致发光光谱对制备的 MoS QDs 的形貌、结构、组成和光学性质进行了表征。结果表明，MoS QDs 具有良好的水分散性，粒径为 2nm 时发射出强荧光。在最佳实验条件下，MoS QDs 的荧光信号在 FOX-7（0.5-100μM）浓度范围内被猝灭，传感器的检测限（LOD）为 0.19μM。该方法已应用于分析实际水样，具有良好的选择性和稳定性。此外，通过傅里叶变换红外（FT-IR）、紫外-可见吸收光谱、荧光寿命和斯特恩-沃尔默方程系统地研究了猝灭机制，证明该机制为静态猝灭。荧光猝灭机制主要为内滤效应和电子转移。
