Electrodeposition of Pt Nanoparticles on New Porous Graphitic Carbon Nanostructures Prepared from Biomass for Fuel Cell and Methanol Sensing Applications

Abstract

We investigate the performance of an iron-doped porous graphitic carbon nanostructure (GCN) prepared from biomass for application in fuel cells and electrochemical sensors. By using cyclic voltammetry (CV), we show that these GCNs have appropriate electrochemical properties and exhibit a significantly high catalytic activity toward oxygen reduction without Pt catalyst. The GCNs were also used as a substrate for electrodeposition of Pt nanoparticles (Pt-NPs) to study electro-oxidation and sensing of methanol. The composition of Pt-NPs and GCNs show high catalytic affinity toward electro-oxidation of methanol in an acidic medium. The modified electrode with Pt-NPs and GCNs also could act as an effective sensor for determination of methanol concentration in natural pH. This sensor enables determination of methanol with a wide linear range (0.05–21.73 mM), low detection limit (20 μM, at S/N of 3), high sensitivity (11.49 μA cm−2 mM−1), and long-term stability (over 40 days). The present sensor also has low working potential (0.17 V) making it less prone to an interference effect. The resulting electrodes were characterized by using scanning electron microscopy, energy dispersive X-ray spectroscopy, and CV.