基于柠檬酸的氮掺杂碳量子点对Fe^(3+)的检测

Detection of Fe^(3+)by Nitrogen Doped Carbon Quantum Dots Based on Citric Acid

以一水合柠檬酸作为碳源,四乙烯五胺作为氮源,利用熔融法合成一种新的氮掺杂碳量子点(N-CQDs),N-CQDs水溶液在紫外光下可发出强烈的蓝色荧光。通过荧光分光光度计确定N-CQDs最佳激发波长为350 nm,利用傅里叶红外光谱仪对N-CQDs的结构进行初步分析,并从保存温度、pH值、光稳定性等方面研究N-CQDs的发光性能。研究结果表明,N-CQDs适合低温酸性条件保存,具有良好的光稳定性;Fe^(3+)对N-CQDs具有强烈的荧光猝灭效应,Fe^(3+)浓度在0~1000μmol·L^(-1)区间内与N-CQDs的荧光猝灭程度(F 0/F)存在良好的线性关系,检出限为9.16μmol·L^(-1)。因此,所合成的N-CQDs可以用于Fe^(3+)的快速检测。

A new nitrogen doped carbon quantum dot was synthesized by melting method using citric acid monohydrate as the carbon source and tetraethylenepentamine as the nitrogen source.Its aqueous solution can emit strong blue fluorescence under ultraviolet light.The optimal excitation wavelength was determined to be 350 nm using a fluorescence spectrophotometer,and its structure was preliminarily analyzed using a Fourier transform infrared spectrometer.Its luminescence performance was studied from aspects such as storage temperature,pH value,and photostability.The results indicate that this carbon dot is suitable for low-temperature acidic storage and has good photostability.And Fe 3+has a strong fluorescence quenching effect on this carbon point.There is a good linear relationship between the fluorescence quenching degree(F 0/F)of the carbon point with Fe^(3+)concentration ranging from 0 to 1000μmol·L^(-1),and detection limit is 9.16μmol·L^(-1).Therefore,the nitrogen doped carbon quantum dots synthesized in this experiment can be used for rapid detection of Fe 3+.