摘要
为了实现水溶液中Fe^(3+)和Hg^(2+)的快速简捷检测,以柠檬酸和硫脲为前驱体,采用一步水热法合成硫、氮共掺杂碳量子点荧光探针。通过透射电镜、傅里叶红外光谱、X射线光电子能谱、荧光分光光度计和紫外-可见吸收光谱分析合成碳点的形貌特征及荧光性能。结果表明:N—S—CDs的平均粒径为8 nm,分布均匀;表面富有各种官能团,具有良好的水溶性;在紫外灯照射下发出强烈的蓝色荧光,荧光量子产率高达36.8%;随激发波长增大,N—S—CDs发射峰荧光强度先增大后减小,在440 nm处荧光强度达到最高,并且其发射峰随着激发波长发生明显红移。N—S—CDs对Fe^(3+)和Hg^(2+)具有较高选择性;Fe^(3+)浓度在40~130μmol/L,Hg^(2+)浓度40~80μmol/L,荧光强度与2种离子呈良好线性关系,线性回归方程分别为F_(0)/F=0.02132c_(Fe^(3+))+0.34945和F_(0)/F=0.18611c_(Hg^(2+))-6.27114;最低检出限分别为1.4、0.16μmol/L;将N—S—CDs用于自来水和湖水的实样分析,可有效检测自来水和湖水中Fe^(3+)和Hg^(2+)。Fe^(3+)的定量回收率为97.16%~103.62%,Hg^(2+)的定量回收率为93.58%~101.22%。
In order to realize the rapid and simple detection of Fe^(3+)and Hg^(2+)in aqueous solution,sulfur and nitrogen co-doped carbon quantum dots fluorescent probes were synthesized by one-step hydrothermal method using citric acid and thiourea as precursors.The morphology and fluorescence properties of the N—S—CDs were analyzed by transmission electron microscope,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,fluorescence spectrophotometer,and ultraviolet-visible absorption spectroscopy.The results showed that the average particle size of N—S—CDs was 8 nm,which was uniformly distributed.The surface was rich in various functional groups and has good water solubility.The strong blue fluorescence was emitted from N—S—CDs under the irradiation of ultraviolet lamp,and the fluorescence quantum yield was as high as 36.8%.With the increase of excitation wavelength,the fluorescence intensity of N—S—CDs emission peak increased at first and then decreased,and the fluorescence intensity reached the highest at 440 nm,and the emission peak was obviously red-shifted with the excitation wavelength.N—S—CDs had high selectivity for Fe^(3+)and Hg^(2+).There was a good linear relationship between the fluorescence intensity and the two ions when the concentration of Fe^(3+)was in the range of 40—130μmol/L and the concentration of Hg^(2+)was in the range of 40—80μmol/L.The linear regression equations are F_(0)/F=0.02132c_(Fe^(3+))+0.34945 and F_(0)/F=0.18611c_(Hg^(2+))-6.27114,and the lowest detection limits were 1.4μmol/L and 0.16μmol/L,respectively.The application of N—S—CDs to the real sample analysis of tap water and lake water could effectively detect Fe^(3+)and Hg^(2+).The quantitative recovery of Fe^(3+)was between 97.16%and 103.62%,and that of Hg^(2+)was between 93.58%and 101.22%.
作者
刘华东
徐浩轩
李合伟
王定标
LIU Huadong;XU Haoxuan;LI Hewei;WANG Dingbiao(School of Mechanical and Power Engineering,Zhengzhou University,Zhengzhou 450001,China)
出处
《郑州大学学报（工学版）》
CAS
北大核心
2022年第6期64-69,共6页
Journal of Zhengzhou University（Engineering Science）
基金
国家自然科学基金资助项目(21576245)
河南省高等学校重点科研项目(21A470005)
河南省自然科学青年基金资助项目(202300410422)。
关键词
CDS
检测金属离子
荧光探针
荧光猝灭
选择性和灵敏度
CDs
detection of metal ions
fluorescence probe
fluorescence quenching
selectivity and sensitivity
