纳米二氧化铈/石墨烯传感器的构建及其对饮品中抗坏血酸的检测

Construction of nano cerium dioxide/graphene sensor and its application in detection of ascorbic acid in beverages

采用滴涂的方式将纳米二氧化铈(CeO_(2))/石墨烯(Gr)混合悬浮液修饰在玻碳电极(GCE)表面,利用Gr优异的导电性与CeO_(2)强催化性的协同效应构建了用于灵敏检测抗坏血酸(AA)的CeO_(2)/Gr/Nafion/GCE传感器。通过循环伏安法(CV)和差分脉冲伏安法(DPV)研究AA的电化学行为并对传感器的各项电化学性能进行分析检测和评价,提升传感器性能进而获得更宽范围、更精确的检测。结果表明,AA浓度在0.1~7.0 mmol/L的范围内与峰电流值呈良好的线性关系,检出限为3.5μmol/L(S/N=3);传感器的重复性、稳定性和选择性良好,并对饮品中AA含量的测定结果较满意。

A mixed suspension of nano cerium dioxide(CeO_(2))/graphene(Gr)is modified on the surface of glassy carbon electrode(GCE)through drop coating method,and the synergistic effect between excellent electrical conductivity of Gr and strong catalytic property of CeO_(2) is utilized to construct a CeO_(2)/Gr/Nafion/GCE sensor for sensitive detection of ascorbic acid.The electrochemical behavior of ascorbic acid is investigated by means of cyclic voltammetry(CV)and differential pulse voltammetry(DPV)to improve the performance of the constructed sensor and to achieve a wider range and more accurate detection in electrolyte solution.It is shown that the peak current shows a good linearity with the concentration of ascorbic acid in the range of 0.1-7.0 mmol·L^(-1),and the detection limit is 3.5μmol·L^(-1).The reproducibility,stability and selectivity of the sensor are also satisfactory,which provides an effective and feasible method for the rapid detection of ascorbic acid in beverages.