Hydrogen sensing properties and mechanism of NiO-Nb2O5 composite nanoparticle-based electrical gas sensors

Abstract

A simple hydrothermal method was used to prepare NiO-Nb2O5 composite nanoparticle electrical sensors for the detection of hydrogen (H-2) at room temperature. To investigate the morphology and crystal structure of the synthesized powders, the synthesized nanoparticles were characterized by scanning electron microscopy and X-ray diffraction. The NiO-Nb2O5 composite nanoparticle sensor showed stronger and faster response to H-2 than the pristine Nb2O5 one at room temperature. Only weak responses were observed to carbon monoxide, methane and ethanol, indicating that the NiO-Nb2O5 composite nanoparticle sensor could be a potential candidate as a practical gas detector. In this study, the H-2 sensing properties and mechanism of NiO-Nb2O5 composite nanoparticle-based electrical gas sensors are discussed in detail.