Study On The Structure And Electrochemical Properties Of Micro-Nano?NiCo₂S₄,CoO/Ni₂O₃,MoFe?@C Composite Electrode

Nowadays,issues such as the rising fossil fuel prices,environmental pollution,global warming and political turmoil are all related to fossil fuels.Therefore,it has become increasingly important to explore new green energy systems with high power and energy density.In this paper,due to the fact that the transition metal has characteristics of the Faraday charge transfer effect,which can store more energy than carbon materials,besides,carbon materials have higher conductivity and excellent cycle performance,the electrochemical performance of several materials such as NiCo₂S₄,CoO,Ni₂O₃ and ferric molybdate were studied.The main experimental conclusions are as follows:1.Flake transition metal sulfides?NiCo₂S₄?were synthesized through a hydrothermal method.By testing the related electrochemical performances,the specific capacitance was 1130 F/g at the current density of 0.5 A/g,the rate performance test was carried out at different current densities,the specific capacitance decreased only by 3.3%?960 F/g?.After 1000 cycles,the specific capacitance still remained 80%of the initial capacitance.The electrochemical performance test was carried out after assembling the sample material into a battery.It can be seen from the GCD curve that the first discharge specific capacitance was832 mA·h/g,and the GCD curve coincidence degree of charge and discharge curve was excellent,indicating a good cycle performance and high coulombic efficiency.The rate performance of the electrode material at different magnifications was relatively stable.2.The layered NiCo@C composites were synthesized with a low-temperature combustion method.On the one hand,the carbon in the sample was activated by KOH,thus the element of Al in the composite was removed,and the specific surface area of the material was increased.On the other hand,carbon material has high electrical conductivity and electric double layer capacitance properties,which can improve the electrochemical properties of the material through synergy.The constant current charge and discharge test of the electrode material showed a specific capacitance of 213 F/g at the current density of 0.6 A/g.After 1000 cycles,its specific capacitance can still remain 77%of the initial specific capacitance.3.MoFe@C composites were synthesized with high temperature solid phase method,the interaction of iron ions and molybdenum ions can provide rich redox chemical active sites and thus we studied its application in the field of supercapacitors.At the same time,methyl orange anodyne was used to simulate the wastewater generated by the textile industry,and the application of the material in photocatalytic degradation of methyl orange was studied.The results showed that at the current density of 1 A/g,the specific capacitance of the electrode was 362 F/g,and after 1000cycles,the specific capacitance can be maintained at 82%of the initial specific capacitance.The degradation rate was approximately 99%when the photocatalytic reaction time was about 55 min.At the same time,from the perspective of economic efficiency and catalytic effect,the degradation rate of methyl orange can achieve an excellent effect when the addition concentration was 1.5 g/L.