A non-enzymatic amperometric hydrogen peroxide sensor based on iron nanoparticles decorated reduced graphene oxide...

A simple and facile green process was used for the synthesis of iron nanoparticles (FeNPs) decorated reduced graphene oxide (rGO) nanocomposite by using Ipomoea pes-tigridis leaf extract as a reducing and stabilizing agent. The as-prepared rGO/FeNPs nanocomposite was characterized by transmission electron microscopy, X-ray spectroscopy and Fourier transform infrared spectroscopy. The nanocomposite was further modified on the glassy carbon electrode and used for non-enzymatic sensing of hydrogen peroxide (H₂O₂). Cyclic voltammetry results reveal that rGO/FeNPs nanocomposite has excellent electro-reduction behavior to H₂O₂ when compared to the response of FeNPs and rGO modified electrodes. Furthermore, the nanocomposite modified electrode shows 9 and 6 folds enhanced reduction current response to H₂O₂ than that of rGO and FeNPs modified electrodes. Amperometric method was further used to quantify the H₂O₂ using rGO/FeNPs nanocomposite, and the response was linear over the concentration ranging from 0.1μM to 2.15mM. The detection limit and sensitivity of the sensor were estimated as 0.056μM and 0.2085μAμM^-1cm^-2, respectively. The fabricated sensor also utilized for detection of H₂O₂ in the presence of potentially active interfering species, and found high selectivity towards H₂O₂.