| The energy problem has always been a key issue threatening human progress and social development,and with the rapid development of today’s technology,solving the energy shortage problem has become a top priority.Although a lot of research has been devoted to the development of new energy sources,new energy sources such as wind and solar are susceptible to environmental fluctuations and cannot meet the requirements in many places where a stable energy supply is needed,so the development of efficient,stable and effective energy storage devices is of great strategic importance and practical application significance.Supercapacitors with long cycle life,high power and energy density,and excellent multiplier performance can meet the needs of human production and life,and are considered to be the most competitive new energy storage devices.As the key device of supercapacitor,electrode material plays a crucial role in the performance of the whole capacitor.There are three common electrode materials:carbon materials,conductive polymers and transition metal compounds.As a representative of transition metal compounds,MnO2 has received a lot of attention from researchers all over the world due to its abundant source,easy synthesis,non-toxic and environmental protection,and high theoretical capacitance value.However,due to the poor conductivity of MnO2,there is still a certain gap between its actual capacitance value and the theoretical capacitance value.In this experiment,the noble metal Ag doping was used to improve the conductivity of MnO2 and thus the electrochemical properties of the material.MOA5 is a hollow sea urchinlike structure formed by the interlap of MnO2 nanowires,which makes the material rich in specific surface area and porosity.The pseudocapacitance of the material is demonstrated by the increased conductivity of Ag doping,which leads to a pair of redox peaks in the CV curve.In this work,spiral ropes of PANI were successfully prepared,and the PANI spiral ropes lapped each other to form a large number of pores.6PMOA5 maintains the spherical structure of MOA5,while a uniform PANI spherical shell is compounded on the surface of MOA5 spheres,which maintains the structural advantages of both materials.Since silver ions(Ag+)can be used as an efficient catalyst to accelerate the oxidation of metal ions in aqueous solutions containing persulfate ions,Ag-MnO2 was prepared at room temperature using Ag+catalysis,and the catalytic,doping and in situ composite were directly completed during the preparation process in order to reduce the influence of the fabrication process on the material properties,and the self-assembled Ag-MnO2 nanowires grown uniformly on the carbon cloth surface using a one-step method The Ag-MnO2/CC selfsupported flexible electrode composites were prepared by a sea urchin-like spherical shell formed on the surface of carbon cloth.The RTMOA1,RTMOA3 and RTMOA5 prepared at room temperature are hollow sea urchin-like structures composed of self-assembled MnO2 nanowires.Due to the high surface area and low crystallinity,RTMOA1,RTMOA3,and RTMOA5 exhibit high capacitance values.In order to solve the phenomenon of MnO2 shedding during electrochemical tests in aqueous electrolyte solutions,a one-step process for the preparation of Ag-MnO2/CC selfsupporting flexible electrode composites was further explored.uniform sea urchin-like MnO2 was successfully grown on carbon cloth in CRTMOA3 and CRTMOA5.The in-situ growth of MnO2 directly on the carbon cloth surface results in a tighter and more uniform bonding between MnO2 and carbon fiber,which prevents MnO2 from being electrochemically dissolved and dislodged during the test in aqueous electrolyte solution.Moreover,the carbon cloth can be used as a buffer to regulate the volume change and related strain release during the charge/discharge cycle,which further increases the electrochemical performance of the material. |
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