| At present,with the rapid development of the economy,the human demand for energy is increasing day by day,and the environmental pollution problems brought about by this are also becoming serious.More and more researchers are working to develop new,non-polluting energy sources that can be recycled.Supercapacitors have attracted much attention due to their superior performance such as fast charge and discharge time and long cycle life.The electrode materials can be divided into electric double layer capacitor materials and tantalum capacitor materials.In this paper,the electrochemical properties of two kinds of tantalum capacitor materials,such as copper ion doped metal oxide?manganese dioxide,zinc oxide?and conductive polymer?polyaniline?,were studied.And the phase characterization tests including FTIR,XRD,SEM,TEM,EDS and nitrogen adsorption and desorption were carried out.The main contents are as follows:1.Copper ion doped manganese dioxide and zinc oxide materials with foamed nickel as conductive substrate were prepared by hydrothermal method.?1?The manganese dioxide was obtained through adjusting the molar ratio of potassium permanganate to manganese sulfate.Electrochemical test results show that when the molar ratio of the two reactants is 3:1,the prepared sample has good electrochemical performance,the specific capacitance is 335.6 F·g-1 at a current density of 1 A·g-1,and after 1500 cycles,the capacitor retention rate is 98.7%.On this basis,copper ion doping was carried out.Electrochemical tests confirmed that the electrochemical properties of materials doped with 0.25 mmol of copper ions were better than single manganese dioxide when the amounts of potassium permanganate and manganese sulfate were 4.5 and 1.5 mmol,respectively,and the specific capacitance was 636.3 F·g-1 at a current density of 1 A·g-1.After 1500 cycles,the capacitor retention rate is 105.01%.?2?The electrochemical properties of the composite prepared were better when the zinc acetate was 4.0 mmol and the doping amount of copper ions was 0.4 mmol.The specific capacitance was 331.5 F·g-1 at a current density of 1 A·g-1.After 1500 cycles,the capacitance retention rate is 77.1%,which is larger than that of single zinc oxide(specific capacitance:122.1 F·g-1,capacitance retention rate:70.4%).2.A simple chemical method was used to synthesize copper ion doped polyaniline composites.First,polyaniline was prepared by adjusting the molar ratio of ammonium persulfate to aniline and the volume of 1 mol·L-1 hydrochloric acid.When the volume of 1mol·L-1 hydrochloric acid used to mix 0.2 mol of L-1 ammonium persulfate solution is 25mL and the ratio of ammonium persulfate to aniline is 1:1?2.5 mmol,respectively?,the obtained polyaniline has the best electrochemical performance,and the specific capacitance of the sample was 286.4 F·g-1 at a current density of 1 A·g-1,the capacitor retention was25.6%after 1000 cycles.On the basis of this,the doping of copper ions was carried out.It was found by electrochemical test that the specific capacitance of the composite prepared when the doping amount was 1.0 mmol under the condition of aniline amount of 2.5 mmol was 302.2 F·g-1,and the capacity retention after the cycle test was 33.3%.Chemical properties slightly better than single polyaniline.The experimental results show that the copper ion doping improves the electrochemical performance of manganese dioxide and zinc oxide,but the effect on polyaniline performance is not significant. |
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