Electrochemically Prepared Three‐dimensional Porous Nitrogen‐doped Graphene Modified Electrode for Non‐enzymatic Detection of Hydrogen Peroxide

A facile and green electrochemical method for the fabrication of three-dimensional porous nitrogen-doped graphene (3DNG) modified electrode was reported. This method embraces two consecutive steps: First, 3D graphene/polypyrrole (ERGO/PPy) composite was prepared by electrochemical co-deposition of graphene and polypyrrole on a gold foil. Subsequently, the ERGO/PPy composite modified gold electrode was annealed at high temperature. Thus 3DNG modified electrode was obtained. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy were used to characterize the structure and morphology of the electrode. The electrode exhibits excellent electroanalytical performance for the reduction of hydrogen peroxide (H2O2). By linear sweep voltammetric measurement, the cathodic peak current was linearly proportional to H2O2 concentration in the range from 0.6 μM to 2.1 mM with a sensitivity of 1.0 μA μM−1 cm−2. The detection limit was ascertained to be 0.3 μM. The anti-interference ability, reproducibility and stability of the electrode were carried out and the electrode was applied to the detection of H2O2 in serum sample with recoveries from 98.4 % to 103.2 %.