Structure Construction And Electrochemical Performance Investigation Of Biomass Derived Porous Carbon Materials Based On Supercapacitor

Supercapacitor is a kind of energy storage device whose energy density is between traditional chemical battery and capacitor.Thanks to its advantages,such as the short charging time,high power density and long cycle life,considered to be a potential that you could use some or all to substitute for chemical battery,bears significant importance to the energy supply and environmental protection.At present,the development of supercapacitors is still limited by low energy density,and the preparation of electrode materials with higher energy density will be a breakthrough point for the development of supercapacitors.With the research of supercapacitors,it is found that better morphology and pore size distribution can significantly improve the electrochemical properties of materials.In this subject,use complex and varied microstructure of biomass as raw material,take advantage of the structure characteristics of biomass to design the preparation of a certain three-dimensional structure of porous carbon materials,and carries on the characterization of a series of experiments and electrochemical performance test,to get a batch of excellent structural stability and low resistance of porous carbon materials,living material model and guidance for the effective development and utilization,for its application in the field of supercapacitor energy storage,such as to provide scientific basis and technical support.The main work is summarized as follows:?1?With taro epidermis as raw material,using the low temperature carbonization technology to retained the plant cell wall structure of itself,and successfully prepared taro epidermis derived cell wall frame structure of porous carbon materials.Through the research on the characterization test and electrochemical properties of the materials,found that cell wall frame structure has provided good electrolyte transport environment,compared with the traditional microporous carbon material,with a small internal resistance,high charge-discharge efficiency,the utilization rate of microporous.In electrochemical test,super capacitor materials show extremely outstanding performance,in the three electrode system,the materials obtained ultra-high specific capacitance of 466.5 F g^-1 in current density at 1 A g^-1,and almost no capacitance fading after 40 000 cycles in current density at10 A g^-1,showing an excellent cycle stability.?2?In this section,the carbon materials were prepared by using the nitrogen-rich yam epidermis as raw materials.The low temperature carbonization technology is still used to reserves the plant cell wall structure of yam epidermis,to have successfully prepared the N-doping yam epidermis derived cell walls frame structure carbon materials,the characterization and electrochemical properties of the materials were also studied.In the study,the cell walls of frame structure of the advantages of good circulation of electrolyte system is still pretty obvious,and yam epidermis's own higher nitrogen content in the preparation of the carbon material with higher nitrogen doping level.This material has performed well performance of supercapacitors,and the high energy density of 23.2 Wh kg^-1 is obtained under the current density of 1 A g^-1 in the aqueous system.?3?The CaCl₂ activation in high temperature can induced and stripping the silk fibroin fiber into carbon nanosheet.The systhesis of carbon nanosheet,compared to previous reported that protein derived carbon material with delicate structure is stronger,and own a certain three-dimensional topography,show a good electrochemical performance.The transformation process of carbon materials from silkworm cocoons to nanosheet carbon materials was analyzed by scanning electron microscope images of the products.Using Na₂CO₃ solution to remove the sericin in the surface of silkworm cocoon and expose the silk fibroin.By using the soaking method,CaCl₂ solution was fully exposed to the degumming silk,and dissolved in the heat,and the regenerated silk protein based carbon nanometer material was prepared.The material has the spatial structure of interleaved interconnection,and the structure is universal and evenly distributed.The green activation method allows the maximum retention of hybrid atoms,and the process does not produce the by-product of environmental hazards,and the equipment requirements are lower.Compared with the surface area of 730 m²g^-1,the material obtained 246 F g^-1 has a considerable development prospect.