Thermally reduced graphene/nafion modified platinum disk electrode for trace level electrochemical detection of iron

Abstract This paper presents a thermally reduced graphene/nafion modified platinum disk electrode (TRG/NF/PDE) for sensitive detection of iron (Fe) using square wave voltammetry (SWV). The graphene was synthesized by thermal exfoliation of graphite oxide in nitrogen atmosphere with an eco-friendly procedure. The morphologies of thermally reduced graphene and thermally reduced graphene/nafion were characterized by field emission scanning electron microscopy (FESEM). Electrochemical behaviors of the electrode before and after modification were studied by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under optimized conditions, the TRG/ND/PDE exhibited excellent electrocatalysis toward Fe. A linear calibration curve was established in the range from 1 to 200 ppb for Fe. With a pre-concentration time of 180 s, a limit of detection based on three times of the background noise was calculated to be 0.08 ppb for Fe. The method was successfully employed for the detection of Fe in real water samples.