Preparation of 3D rose-like nickel oxide nanoparticles by electrodeposition method and application in gas sensors

3D rose-like NiO nanoparticles have been prepared by electrodeposition method. The samples were characterized through X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The phase and morphology observations showed the formation of rose-like hierarchical structures with an average particle diameter of 400–500 nm. Gas sensing properties of the as-synthesized rose-like NiO nanoparticles were evaluated by the detection of volatile and toxic gases including ethanol, methanol, and acetone. It was found that NiO nanoroses exhibited a highly response to the three gases at 230 °C. Furthermore, at 5 ppm, the NiO nanorose-based sensor gave a higher response to ethanol ( R g / R a = 9.11) and methanol ( R g / R a = 8.36), in comparison with acetone ( R g / R a = 6.44). The results indicated the NiO nanorose-based sensors displayed a rapid response and recovery as well as good reproducibility.