A Modified Glassy Carbon Electrode for Hydrogen Peroxide Sensing

In this paper, 4-ferrocenyl benzoic acid (FcBA) was synthesized and the electrochemical behaviors of the synthesized ferrocenyl derivative were studied; Then, the multi-wall carbon nanotubes (MWCNTs) coated FcBA modified glassy carbon (MWCNTs/FcBA/GC) electrode was prepared conveniently and the as-prepared modified electrode was characterized with both electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM). The results suggested that FcBA could coat the MWCNTs tightly in dimethylformamide (DMF) and the coated MWCNTs could be strongly adsorbed on the surface of glass carbon (GC) electrode. The MWCNTs/FcBA/GC electrode exhibited an excellent electrocatalytic activity toward the reduction of hydrogen peroxide. The modifiedelectrode was hence used for the determination of hydrogen peroxide by differential pulse voltammetry (DPV). The linear range of the modified electrode was 2.5×10-6 and 5.0×10-4 mol/l, and the detection limit was estimated to be of 4.8×10-7 mol/l when the signal-to-noise ratio was 3. Further studies indicated that the modified electrode was of a fast response, high sensitivity, good reproducibility, and long-term stability.