基于Ti_(3)C_(2)/CuS纳米复合材料修饰电极快速扫描循环伏安法检测痕量汞离子  

Determination of Trace Mercury Ions by Ti_(3)C_(2)/CuS Composite Modified Glassy Carbon Electrode Combined with Fast Scan Cyclic Voltammetry

作　　者：纪权 鲁理平[1] JI Quan;LU Li-Ping(Key Laboratory of Beijing on Regional Air Pollution Control,Faculty of Environment and Life,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学环境与生命学部,区域复合污染防治北京市重点实验室,北京100124

出　　处：《分析化学》2023年第12期1915-1923,共9页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.22276005,21876005);北京市卓越青年科学家计划项目(No.BJJWZYJH01201910005017)资助。

摘　　要：构建了一种基于多功能纳米复合材料Ti_(3)C_(2)/CuS修饰玻碳电极(Ti_(3)C_(2)/CuS/GCE)的电化学传感平台,并采用快速扫描循环伏安法(FSCV)检测痕量汞离子(Hg^(2+))。利用Ti_(3)C_(2)MXene的高导电性提高传感界面的电荷传递能力,并利用CuS溶度积常数小于HgS的特点实现高选择性测定Hg^(2+)。在Ti_(3)C_(2)/CuS/GCE上,考察了不同扫描速率(0.1和350 V/s)下常规CV和FSCV对Hg^(2+)的分析性能,结果表明,超快扫速可显著增强电流信号。在最佳实验条件下(缓冲溶液pH=6、复合材料滴涂体积为5μL、吸附时间为15 min以及扫描速率为350 V/s),本方法测定Hg^(2+)的线性范围为0.5~50 pmol/L,检出限为0.5 pmol/L(S/N=3),并具有良好的选择性、稳定性和重现性。将本方法用于实际湖水样品中痕量Hg^(2+)的测定,回收率为97.4%~102.3%,相对标准偏差<3.6%,表明本方法在Hg^(2+)的应急检测和现场检测领域具有良好的应用前景。A fast scan cyclic voltammetry(FSCV)electrochemical sensor based on multifunctional nanocomposite material Ti_(3)C_(2)/CuS for detection of trace mercury ions(Hg^(2+))was constructed in this work.Firstly,the high conductivity of Ti_(3)C_(2)MXene was utilized to improve the charge transfer ability of the sensing interface.Secondly,the determination of Hg^(2+)with high selectivity was achieved by utilizing the characteristic of CuS solubility product constant being less than HgS.And by comparing the cyclic voltammetry phenomena under conventional scanning speed(0.1 V/s)and ultrafast scanning speed(350 V/s),it was found that on the basis of high-performance interface modification,ultrafast scanning speed could further enhance the current signal significantly.Under the optimal testing conditions,including buffer solution at pH=6,5μL of composite material drop coating volume,and at an adsorption time of 15 min and a scanning rate of 350 V/s,the linear range for detecting Hg^(2+)was 0.5–50 pmol/L,and the detection limit was 0.5 pmol/L(S/N=3).This sensor had good selectivity,stability and reproducibility,and could be used for determination of trace mercury in actual lake water samples,with recoveries of 97.4%–102.3%and relative standard deviations<3.6%.The sensor was expected to have broad application prospects in emergency and on-site detection.

关 键 词：快速扫描循环伏安法 痕量汞离子 化学修饰电极 电化学传感器 

分 类 号：O657.1[理学—分析化学] TB33[理学—化学]