Electrochemical Determination of Nitrite Using a Reduced Graphene Oxide–Multiwalled Carbon Nanotube-Modified Glassy Carbon Electrode

Abstract

Graphene oxide nanosheets were encapsulated with multiwalled carbon nanotubes by direct reduction on glassy carbon to obtain a reduced graphene oxide/multiwalled carbon nanotube-modified electrode. The encapsulated multiwalled carbon nanotubes facilitated the reduction of graphene oxide with characterization by atomic force microscopy, scanning electron microscopy, and Raman spectroscopy. The reduced graphene oxide–multiwalled carbon nanotube-modified electrode exhibited high catalytic activity for the oxidation of nitrite. Under the optimized conditions, the modified electrode had a linear dynamic range from 0.2 to 640 µM with a detection limit of 0.07 µM. This device was used to determine nitrite in water samples and satisfactory results were obtained.