Syntheie And Electrochemical Properties Of Cobalt Tetroxide Modified Electrode Materials

Electrochemical sensors and supercapacitors have attracted a lot of researchers,and the performance of these two depends on the design and development of electrode materials.As we all know,Co₃O₄nanoparticles have high surface area to volume ratio and catalytic efficiency,but they have low electrical conductivity in practical application,and poor cyclic stability.It is found that other semiconductor materials doped can greatly improve the conductivity.In particular,nickel as a transition metal has excellent conductivity and abundant content.And then,graphene as a carrier can increase substantially the specific surface area of electrode materials,and has unique electronic properties,which enabled graphene graphene composite electrode to have a great improvement and breakthrough compared with traditional analysis methods in terms of sensitivity and detection limits.Therefore,the work prepared Ni-doped Co₃O₄and Co₃O₄/graphene modified electrode materials,and the material characterization and electrochemical performance testing and analysis.The specific research work are as follows.1.A powder doped with elemental nickel and cobalt tetroxide was prepared by hydrothermal method.The electrochemical properties of the powder materials were studied by voltammetry characteristic cycle method.In other words,Ni doped Co₃O₄powder was firstly decomposed and produced.The results show that the Ni-doped Co₃O₄ composites with flower-like morphology are prepared from different cobalt sources.The specific capacitance of the composites is 670 F.g^-1,and the doping mechanism is calculated from the first principles.It is revealed that the electrochemical modified electrode greatly improves the conductivity of the materials.2.A novel nanocomposite electrode（Co₃O₄/GR/GCE）was prepared by electrodeposition of metal oxide cobalt tetroxide（Co₃O₄）/graphene（GR）nanomaterials on the surface of glassy carbon electrode by combining electrospinning technology and electrochemical method,which has been successfully used for the determination of ofloxacin.The surface morphology of the modified electrode was characterized by scanning electron microscopy.Co₃O₄ nanoparticles and GR can be well modified on the surface of the glassy carbon electrode.The differential pulse method was used to optimize the determination conditions of ofloxacin.Under the optimal conditions,the linear relation range was 0.45-170μM,the lowest detection limit was 0.16μM（S/N=3）,and the recoveries were good in practice,the relative standard deviations were less than5%.The experimental results show that the modified electrode has good electrocatalytic performance for ofloxacin,good repeatability,strong practicability,and can significantly improve the sensitivity of detection.3.Co₃O₄composite electrode materials with different amounts of aluminum were prepared by precipitation,and XRD and morphology were analyzed.After electrochemical performance test,it can be seen that its electrochemical performance is the best when the molar ratio of cobalt aluminum is 2:1,the specific capacitance at 5m A current is 566.9 F.g^-1,and its capacitance retention rate is 73.8%after 5000 cycles of charge and discharge,with good cycle stability.