Functionalization of graphene with Prussian blue and its application for amperometric sensing of H2O2

As a two-dimensional carbon material with high surface area and conductivity, graphene shows great promise for designing composite nanomaterials to achieve high-performance electrochemical devices. In this work, we prepared graphene-based nanocomposite material by electrochemically depositing Prussian blue (PB) nanoparticles on the surface of graphene. Fourier transform infrared spectra, SEM, and cyclic voltammetry were used to characterize the successful immobilization of PB. Compared with PB films and graphene sheets, the PB-graphene composite films showed the largest current response to the reduction of H2O2, probably due to the synergistic effects between graphene sheets and PB nanoparticles. Therefore, a fast and highly sensitive amperometric sensor for H2O2 was obtained with a detection sensitivity of 1.6 mu A mu M-1 H2O2 per cm(2) and a linear response range of 50 similar to 5,000 mu M. The detection limit of H2O2 was 20 nM at a signal-to-noise ratio of 3. These obtained results are much better than those reported for carbon nanotubes-based amperometric sensors.