基于乙醇胺-离子液体凝胶水热合成掺氮碳点及其在Cr(Ⅵ)检测中的应用

Nitrogen-doped Carbon Dots based on Hydrothermal Synthesis of Ethanolamine-ionic Liquid Gel and Its Application in Cr(Ⅵ) Detection

本文以乙醇胺和1-羧乙基-3-甲基咪唑氯盐为原料,通过一步水热法制备了具有蓝色荧光的氮元素掺杂碳点(NCDs)。通过XRD、荧光光谱、FT-IR、XPS、TEM等技术手段,对NCDs的表观形貌、光学性能及其结构组成进行表征,结果表明合成的NCDs平均粒径为4.8 nm,量子产率为24.7%,同时NCDs表面含有-COOH,-OH和-NH_(2)等官能团,因此与水溶液具有较好的相容性。基于Cr^(6+)对NCDs荧光的内滤效应,建立了一种选择性检测Cr^(6+)的荧光探针,NCDs的荧光猝灭效率与Cr^(6+)浓度在0~100μM范围内具有明显的线性关系,且检测限为0.063μM/L。另外,按照标准加入法将NCDs荧光探针用于检测自来水样中Cr^(6+),回收率为101.5%~105.0%。

Nitrogen doped carbon dots (NCDs) with blue fluorescence were prepared by one-step hydrothermal method from ethanolamine and1-carboxyethyl-3-methylimidazolium chloride salt.Combined with the characterizations of TEM,XPS and TGA,it was found that CNDs was possessed functional group such as-COOH,-OH and-NH_(2) on the surface,and the fluorescence CNDs was with the particle size of 4.8 nm and the quantum yield of 24.7%,which illustrates this kind of carbon dots were of excellent water solubility.Therefore,a selective fluorescence probe for detecting Cr^(6+)was established based on the internal filtration effect of Cr^(6+)on the fluorescence of NCDs.The fluorescence quenching efficiency of NCDs was linearly correlated with the concentration of Cr^(6+)in the range of 0~100μM,and the detection limit was 0.063μM/L.In addition,it was applied to the detection of Cr^(6+)in real water samples by standard addition method,and the recurrence rate was 101.5%~105.0%.