抗坏血酸在钴酞菁修饰碳糊电极上的电化学行为  

Electrochemical behavior of ascorbic acid at cobalt phthalocyanine modified carbon paste electrode

作　　者：顾玲[1] 柯苗[1] 闫璟[1] 石爱华[1] GU Ling;KE Miao;YAN Jing;SHI Ai-hua(Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry Ministry of Education,College of Chemistry & Chemical Engineering,Shaanxi University of Science&Technology,Xi, an 710021,China)

机构地区：[1]教育部轻化工助剂化学与技术重点实验室,陕西科技大学化学与化工学院,陕西西安710021

出　　处：《化学研究与应用》2017年第2期173-177,共5页Chemical Research and Application

摘　　要：采用掺杂的方法制备了钴酞菁修饰碳糊电极(CoPc/CPE)。利用循环伏安法(CV)和交流阻抗谱(EIS)对修饰电极的电化学性能进行研究,并采用扫描电子显微镜(SEM)观察其表面形貌。运用循环伏安法(CV)、线性扫描伏安法(LSV)、计时电流法(CA)以及计时电量法(CC)研究了抗坏血酸在该修饰电极上的电化学行为并计算了电极过程的动力学参数。结果表明CoPc/CPE对抗坏血酸有明显的电催化作用,抗坏血酸在该修饰电极上的电极反应受扩散控制。计算了抗坏血酸的部分动力学参数:电荷转移系数(α=0.993),扩散系数(D=1.36×10^(-4)cm^2·s^(-1))以及电极反应速率常数(kf=1.62×10^(-2)cm·s^(-1));采用LSV测得抗坏血酸的氧化峰电流与浓度在1.00×10^(-3)(1.00×10^(-6)mol·L^(-1)范围内表现出良好的线性关系,检出限为5.00×10^(-7)mol·L^(-1)(S/N=3)。该修饰电极制备方法简单、灵敏度高、稳定性好,用于实际样品中抗坏血酸的含量分析,结果令人满意。A cobalt phthalocyanine modified carbon paste electrode(CoPc/CPE)was prepared by doping.The electrochemical prop-erties of the modified electrode were characterized by cyclic vohammetry(CV)and electrochemical impedance spectroscopy(EIS),the surface morphology of the modified electrode was observed by scanning electron microscopy(SEM).The electrochemical behav-ior of ascorbic acid at the CoPc/CPE was investigated by cyclic voltammetry(CV),liner sweep voltammetry(LSV),chronoamper-ometry(CA),chronocoulometry(CC),at the same time,some kinetic parameters of ascorbic acid were determined.The results indi-cated that CoPc/CPE had obviously electrocatalytic activity toward ascorbic acid,and the electrode reaction of ascorbic acid exhibi-ted a diffusion-controlled process.Some kinetic parameters such as the electron transfer coefficient(a=0.993),diffusion coefficient(D=l.36x104cm2*s1)and the electrode reaction rate constant(=1.62x102cm*s1)of ascorbic acid were calculated.The oxidation peak currents and concentrations of ascorbic acid had a good linear relationship in the range from1.00x103mol?L1to1.00x106mol?L1with a detection limit of5.00x107mol?L!(S/A^=3)by liner sweep voltammetry(LSV).Furthermore,the preparation process of CoPc/CPE is simple.And the electrode has high sensitivity and good stability,it can be applied to the quanti-tative determination of ascorbic acid in practical samples with satisfactory results.

关 键 词：钴酞菁 抗坏血酸 碳糊电极 电催化 

分 类 号：O657.1[理学—分析化学]