Facile Synthesis of Rose-Like NiO Nanoparticles and Their Ethanol Gas-Sensing Property

In this study, rose-like nickel oxide (NiO) nanoparticles with diameters of 400–500 nm are prepared on ITO glass substrates by simple electrodeposition in NiSO₄6H₂O solution at room temperature followed by oxidation in air. Scanning electron microscopy, x-ray diffraction and a transmission electron microscope are used for analyses of the NiO nanoparticles. The ethanol gas sensitivity of these nanoparticles is studied. The results indicate that the rose-like NiO nanoparticles could be used for the fabrication of ethanol gas sensors to monitor the low concentration of ethanol gas in air. Furthermore, at 5 ppm, the NiO nanorose-based sensors show a high response to ethanol (R_g/R_a=8.4).