One-step preparation of a composite consisting of graphene oxide, Prussian blue and chitosan for electrochemical sensing of hydrogen peroxide

We report on the single-step preparation of a composite consisting of graphene oxide (GO), Prussian blue (PB) and chitosan (Chit) that was deposited on a glassy carbon electrode and then used to determine hydrogen peroxide. The composite was obtained by mixing GO, Chit, potassium ferricyanide and ferric chloride and keeping it at 90 °C for 1 h. This method is simple and inexpensive, and does not require purification, centrifugation or sedimentation. Scanning electron microscopy, UV-vis spectroscopy, Fourier transform IR spectroscopy and X-ray diffraction were used to characterize the GO-PB-Chit composites and revealed that PB nanoparticles were formed and uniformly distributed on the surfaces of the GO due to the integrating effects of Chit and GO. The composite displayed electrocatalytic activity in the reduction of hydrogen peroxide to which it responded with good linear relationship in the 1.0 μM to 1.0 mM concentration range, with a detection limit of 0.1 μM (at S/N = 3).