Research Hierarchy Nickel-based Composite Design Synthesis And Gas Sensing Performance

In this paper, the α-Ni(OH)2/CNT nanocomposites with3D hierarchical structureand NCDH nanocomposites with highly mesoporou hierarchical were prepared througha simple reflux method.NCDH nanocomposite with3D hierarchical structure was synthesized by changingof the CNT concentration. Nickel nitrate as Nickel source, urea (CO(NH2)2) asprecipitants.The material has good gas sensing response to NOxat room temperature.The sample with20mg CNT has the fastest response and the highest sensitivity to97ppm NOx, the response time is8s and sensitivity is24%, its limit level is0.97ppm.The result of gas mechanism study shows that the additions of CNT increase thecomposites conductivity and gas transmission capacity.Highly mesoporou hierarchical nickel and cobalt double hydroxide composite(NCDHs) have been synthesized via a simple reflux method. The synthesized withNCDHs composite with the mass ratio of100:20forNi(NO3)2·6H2O/Co(NO3)2·6H2O (NCDH-20) contained a lot of oxygen defect sites,and chemisorbed water connect the adjacent Ni(OH)2layers. The porous hierarchicalnanostructures provide natural channels for the effective and fast transportation ofcarriers. Futhermore, the NCDH-20sensor exhibits excellent gas-sensing properties thatis low detection limit of0.97ppm, short response time of0.6s to97ppm NOx.In summary, the α-Ni(OH)2/CNT nanocomposites with3D hierarchical structureand NCDH nanocomposites with highly mesoporou hierarchical have fast-response toNOxat room temperature. It looks forward to promising material in gas sensing field.