氮硫掺杂碳点的制备及检测铜离子  

Synthesis of Sulfur and Nitrogen Doped Carbon Dots for Cu(Ⅱ)Detection

作　　者：齐海燕[1] 张琛琪 李金龙 李军 QI Hai-Yan;ZHANG Chen-Qi;LI Jin-Long;LI Jun(Qiqihar University Institute of Chemical Engineering,Qiqihar 161006,China;Key Laboratory of Fine Chemicals of College of Heilongjiang Province,Qiqihar 161006,China;Heilongjiang Industrial Hemp Processing Technology Innovation Center,Qiqihar 161006,China)

机构地区：[1]齐齐哈尔大学化学与化学工程学院学院,齐齐哈尔161006 [2]黑龙江省精细化学品催化合成重点实验室,齐齐哈尔161006 [3]黑龙江省工业大麻加工技术创新中心,齐齐哈尔161006

出　　处：《应用化学》2022年第6期980-989,共10页Chinese Journal of Applied Chemistry

基　　金：黑龙江省省属高等学校基本科研业务费科研项目(No.300882);齐齐哈尔市科学技术计划(No.GYGG-201903)资助。

摘　　要：以柠檬酸为碳源,通过水热合成制备N、S掺杂的蓝色荧光碳点(NS-CDs),用于实际样品中铜离子检测。采用高分辨率透射电子显微镜、X射线衍射光谱、红外吸收光谱、X射线光电子能谱、荧光光谱对其结构、组成和光学性质进行表征。结果表明,NS-CDs分散性好,尺寸分布在0.6~2.2 nm之间,具有无定形碳的结构;碳点表面含有羟基、羧基、酰胺等官能团,C、N、O和S元素质量分数别为54.01%、24.49%、19.39%及2.11%;该碳点具有良好的耐盐性、pH稳定性、光稳定性,其荧光量子产率为25%。基于Cu^(2+)离子与碳点表面多个官能团发生相互作用形成聚集的网络结构,导致荧光猝灭的现象,建立了检测Cu^(2+)的荧光分析新方法,本方法对Cu^(2+)离子具有良好的选择性和较高的灵敏度,在0.2~10、10~50和50~100μmol/L范围均有良好的线性响应,检出限为41 nmol/L(S/N=3)满足《土壤环境质量标准》对土壤中Cu^(2+)检测国家标准的要求(6.25 mmol/L)。测定了实际土壤中Cu^(2+)的含量,检测结果为2.55μmol/L,加标回收率在104.9%~105.6%之间,实现了Cu^(2+)的快速、灵敏、高选择性检测。Nitrogen and sulfur co-doped blue fluorescent carbon dots(NS-CDs)for detection of copper ion in real samples were prepared by the hydrothermal method using citric acid as the carbon source.The structure,composition and optical properties of NS-CDs were characterized by high-resolution transmission electron microscopy,X-ray diffraction,infrared absorption spectroscopy,X-ray photoelectron spectroscopy,and fluorescence spectroscopy.The results show that the NS-CDs have amorphous carbon structure,high dispersibility,and its particle size is in the range of 0.6~2.2 nm.There are carboxyl,hydroxyl and amide functional groups on NS-CDs′surfaces.The C,N,O and S element contents of NS-CDs are 54.01%,24.49%,19.39%and 2.11%,respectively.NS-CDs show good fluorescence stability for the irradiation by ultraviolet light,pH value,and ionic strength,and the fluorescence quantum yield is 25%.Cu^(2+) could interact with the functional groups on NS-CDs,resulting in the aggregation/network structure and causing quenching of fluorescence intensity.A fluorescence analysis method is established to detect Cu^(2+) with linear ranges of 0~10,10~50 and 50~100μmol/L,respectively.The detection limit is achieved as 41 nmol/L(S/N=3),which meets the Chinese guidelines for Cu^(2+) in soil in Environmental Quality Standard for Soils.The method is successfully applied in detection of Cu^(2+) in soil samples with recoveries of 104.9%~105.6%.The copper ion concentration is 2.55μmol/L.The method is rapid,sensitive and highly selective for detection of Cu^(2+).

关 键 词：掺杂碳点 荧光猝灭 铜离子 检测 

分 类 号：O652.1[理学—分析化学]