The Preparation Of Metal Oxide Composite Fibres By Electrochemical Spinning And Their Electrochemical Performance

The energy crisis and environmental deterioration make researchers pay more attention to the exploration of new energy and energy storage technology.Super capacitor also known as electrochemical capacitor,because of its high energy density,green pollution-free,good cycle performance and so on,It has become a hot spot in the field of electrochemical energy storage.The electrode material of super capacitor directly affects the electrochemical performance of super capacitor.In this paper,nickel,cobalt,manganese oxide and its composites were prepared by electro spinning used for the electrode material of super capacitor.The materials were characterized by XRD,SEM,TEM,XPS and so on;The electrochemical properties of the materials were tested by three electrode system,It mainly includes cyclic voltammetry?CV?,charge and discharge test,and the cycle performance of the electrode material.The results are as follows:?1?PVP/Ni?CH₃COO?₂/Zn?CH₃COO?₂ nanofiber composites were prepared by electro spinning,then NiO-Zn O nanofibers were obtained at heat treatment temperature of 550 ? with Zn:Ni=0:1,1:20,2:20 and 3:20?molar ratio?.Cyclic voltammetry and galvanostatic charge / discharge tests were performed in 1mol/LKOH electrolyte.The results show that under the same calcination conditions,the specific capacitance of the composite electrode with Zn:Ni ratio of 0:1,1:20,2:20 and 3:20 was 332F/g,375 F/g,441 F/g,and 412 F/g respectively,in the current density of 1A/g.Among them,2:20 composite has a maximum capacitance of 441F/g,which is 35.6% higher than that of pure nickel oxide nano fiber composites.With 1000 cycles of charging and discharging,the specific capacitance retention rate of 2:20 sample is up to 82.1%,which shows good playback stability.?2?The preparation of cobalt manganese oxide nanofiber composites was by electrospinning at 500 ? with Mn: Co=0:1,1:20,2:20,3:20?molar ratio?..By cyclic voltammetry,galvanostatic charge discharge test,the specific capacitance of the electrode material of Mn: Co ratio of 0:1,1:20,2:20,3:20 under the current density of 1A/g was 416 F/g,454 F/g,585F/g and 429 F/g respectively.The 2:20 composite is excellent and has a maximum capacitance of 585F/g higher than that of pure cobalt oxide nanofiber compistes by 40.6%.Compared with the NiO-ZnO nanofibers,the 2:20 Co₃O₄-MnO₂ nanofibers have better specific capacitance,which is especially maintained about 82.6% after 500 cycles of charging and discharging,showing good electro-chemical stability.?3?)MnO₂ and Mn₃O₄ nanofibers were prepared by electrospinning respectively and their electrochemical properties were tested,For MnO₂ fibers,under the current density of 1A/g,their specific capacitance is 366 F/g,and after 500 cycling the capacitor is kept at a rate of about 71%.But for Mn₃O₄ nanofibers,under the current density of 1A/g,their specific capacitance is 247 F/g and their capacitance retention is74% after the 500 cycles.It is obvious the performance of MnO₂ nanofibers are better than Mn₃O₄ nanofibers.