多巴胺在电沉积钻鎳氢氧化物—氮掺杂石墨烯修饰电极上的电化学行为

On Electrochemical Behavior of Dopamine at Electrodeposited Cobalt-Nickel Hydride-Nitrogen Doped Graphene Modified Electrode

采用循环伏安电沉积法,在氮掺杂石墨烯修饰玻碳电极上电沉积链镰的氧化物,然后在氢氧化钠溶液中电化学洽化,采用循环伏安和交流阻抗法对电极进行了电化学表征,研究了多巴胺在该洽化电沉积电极上的电化学行为.优化了电沉积的扫描圈数、电化学洽化时间、支持电解质等条件.在最佳条件下,多巴胺在该电极上呈现出良好的可逆响应,峰电住差降低到34 mV,峰电流相对于裸电极增大50余倍.其峰电流Ipc与浓度c在5.0×10^-7~1.0×10^-4mol/L范围内表现出明显的线性关系,线性方程为:Ipc(10^-7 A)=-0.4712-0.1973c(μmol/L),R=0.9970,检出限(S/N=3)为3.2×10^-8mol/L.该电极具备良好的重现性、稳定性、低检出限和良好的回收率,有望用于多巴胺的实际测定.

Cobalt-Nickel oxide were electrodeposited on the nitrogen doped graphene modified glassy carbon electrode by cyclic voltammetry,then the electrodeposited membrane was activated in NaOH solution to form hydride,and the proposed modified electrode was characterized by cyclic voltammetry and electrochemical impedance spectroscopy.The electrochemical behavior of dopamine was studied at the proposed electrode.The experimental conditions,such as scans of electrodeposition,time of electrochemical activation and supporting electrolyte were optimized・Under optimum conditions,dopamine shows favorable reversible effect at the proposed electrode with decreasing of peak separation of 34 mV and increasing current about 50 times than that of dopamine at bare electrode.The peak current is linear to its concentration from 5.0×10-7 to 1.0×10-4mol/L with a regression equation of Ipc(10-7A)=-0.4712-0.1973c(ymol/L)and detection limit of 3.2×10-8 mol/L.The proposed electrode shows favorable stability,reproducibility,low detection limit and favorable recoveries,can be used for the determination of DA in the near future.