Sensitivity of Chitosan Film Based Electrode Modified with Reduced Graphene Oxide (rGO) for Formaldehyte Detection Using Cyclic Voltammetry

Abstract

This paper reports the ability of chitosan-reduced graphene oxide (rGO) modified electrode as a sensitive layer of working electrode in detecting formaldehyde. The electrode substrate is in the form of copper-SPE which has been shaped into 5 mm of sensitive area. On top of the working electrode, a number of chitosan and chitosan-reduced graphene oxide (rGO) matrices were placed in the form of a thin film layer that works as a working electrode. Characterization of chitosan and chitosan-reduced graphene oxide (rGO) thin films was done using SEM, TEM, AFM and FTIR. The test for electrochemical sensing ability of working electrode was observed using cyclic voltammetry (CV), whereas chitosan and chitosan-rGO films were deposited onto the surface of working electrodes. The novelty of this research is the utilization of chitosan-rGO thin film based working electrode for detecting formaldehyde. The testing results showed sensitivity and response of working electrode increased when chitosan-reduced graphene oxide modified electrode was used for formaldehyde detection compared to chitosan film based working electrode. It was proven from the sensitivity value of chitosan-rGO based working electrode at the lowest value of 4.6 × 10−4 µA/µM and linear range at 1–12 × 10−4 µM/L, as well as the ability of chitosan-rGO based working electrode which worked at limit of detection (LoD) 0.36 µM/L and limit of quantification (LoQ) 1.21 µM/L.

Keywords

• Chitosan
• Cyclic voltammetry
• Electrochemistry
• Reduced graphene oxide
• Working electrode