Iron/Iron(III) Oxide Decorated on Electrochemically Reduced Graphene Oxide: a Novel One-Step Electrosynthesis and a Fabrication of an Electrochemical Ascorbic Acid Sensor

Abstract Considering on required detection time and sensitivity, electrochemical method is an excellent candidate for ascorbic acid (AA) sensing. We propose using the synergistic effects of iron(0)/iron(III) oxide decorated on the electrochemically reduced graphene oxide (ERGO/Fe-Fe2O3) modified Pt microelectrode as an electrochemical AA sensor using cyclic voltammetry (CV) technique. Herein, ERGO/Fe-Fe2O3 was directly fabricated on the Pt microelectrode using a novel one-step electrosynthesis. Fe-Fe2O3 acts as an oxidized-nanozyme with works as redox centers on the electrode for oxidation of AA. Fe-Fe2O3 nanozymes are immobilized on electrochemically reduced graphene oxide (ERGO), which supports a large electroactive and excellent electrically conductive surface for electron-transfer during electrochemical oxidation of AA. The developed electrochemical sensor allowed for sensing AA in medical samples with high sensitivity in concentration range from 0.05 to 10.00 mM and a limit of detection (LOD) of 5.93 μM.