Simultaneous determination of catechol and hydroquinone in graphene modified electrode

A novel graphene modified glassy carbon electrode was fabricated.The resulting substrates were characterized by Cyclic Voltammetry and EIS in [Fe(CN)6]3-/4-solution and showed the electrochemical behavior of catechol and hydroquinone on the graphene modified glassy carbon electrode.Experiment result shows that the catechol oxidation peak potential is 270 mV and reduction peak potential is 161 mV,and the hydroquinone oxidation peak potential is 145 mV and reduction peak potential is 64 mV on the graphene modified electrode,respectively.The oxidation peak potential distance is about 125 mV and the reduction peak potential distance is about 97 mV of catechol and hydroquinone which are suited for the simultaneous detection.Catechol and hydroquinone have good electrocatalytic activity on modified electrode and the peak currents of differential pulse voltammetry are liner to the catechol and hydroquinone over the range of 5.0×10-6-1.0×10-4 mol/L,respectively,and the graphene modified electrode can simultaneously detect catechol and hydroquinone in the rang of 8.0×10-5-1.0×10-3 mol/L.The catechol detection limit is 5.0×10-7 mol/L,the hydroquinone detection limit is 1.0×10-7 mol/L.So the graphene modified electrode can be used for analysis the facilitation of actual samples and electrochemical sensors and biosensors.