Characterization of nickel oxide decorated-reduced graphene oxide nanocomposite and its sensing properties toward methane gas detection

A high-performance methane gas sensor based on nickel oxide (NiO)/reduced graphene oxide (rGO) nanocomposite film was reported in this paper. The hydrothermal synthesized NiO/rGO hybrid nanocomposite was fabricated on a ceramic tube as sensing film. The nanostructures of the NiO/rGO nanocomposite film were characterized by scanning electron microscopy, X-ray diffraction and transmission electron microscope. The methane gas sensing behaviors of the sensor samples were investigated by exposing to various concentration of methane gas at different operating temperature. As a result, the presented sensor exhibited high-response, good repeatability and acceptable selectivity toward methane gas detection. The possible gas sensing mechanism of the proposed sensor was attributed to the Fermi energy band between rGO sheets and NiO nanoparticles. This observed results highlight the hydrothermal synthesized NiO/rGO nanocomposite film can be used as a candidate material for constructing methane sensors, given its simple process, practical usability and cost effectiveness.