Electrochemical study of Sudan I at ionic liquid-reduced graphene oxide modified electrode

•IL-rGO nanocomposite was prepared by a simple and green method.•IL-rGO/GCE exhibited good electrochemical response toward oxidation of Sudan I.•Electrochemical mechanism was proposed and discussed in detail.•The proposed mechanism was confirmed further by CV experiments.

Ionic liquid-reduced graphene oxide modified electrode (IL-rGO/GCE) was fabricated using a simple and green method, and it exhibited good electrochemical response on Sudan I. The electrochemical behavior of Sudan I was studied sufficiently, and two electrons and two protons are involved in the electrochemical process of Sudan I at IL-rGO/GCE. Some dynamic parameters such as the diffusion coefficient (D) and adsorption capacity (Г⁎) were calculated as D = 1.43 × 10− 6 cm2/s, Г⁎ = 1.97 × 10− 10 mol/cm2 by chronocoulometries. Meanwhile, supported by cyclic voltammetry experiments, the possible electrochemical reaction mechanism of Sudan I was proposed, which is E1CE2 process. Finally, the effect of initial potential and the scanning direction on the electrochemical reaction of Sudan I confirmed further the proposed electrochemical reaction mechanism. This study probably offers the possibility for preparation an excellent Sudan I sensor.

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