Research On The Preparation Of Electric Double-layer Capacitor Carbon Electrode Materials Based On Polyaniline

Adjusting the energy structure,reducing fossil energy consumption and developing renewable energy is an important way to solve the problems of environmental pollution and energy depletion.Renewable energy is difficult to be used directly due to its discontinuity,lack of corporate control and low conversion efficiency.The development of new energy storage equipment is a necessary measure to balance the deviation between renewable energy generation and load.Supercapacitor is a new type of energy storage device with great application potential,which has the advantages of high-power density,long cycle life and wide working temperature range.However,the lower energy density limits the application scenarios of supercapacitors.The energy density of supercapacitors is determined by its specific capacitance and rated voltage.The specific capacitance mainly depends on the specific surface area and pore structure of the electrode material.Carbon-based materials are ideal electrode materials for supercapacitors due to their large specific surface area,rich pore structure,low cost,and wide range of sources.The development of new carbon-based electrode materials is the key to increasing the energy density of supercapacitors.To increase the energy density of supercapacitors while maintaining their high-power density.In this study,polyaniline（PANI）was used as a precursor,and a method of preparing nitrogen-doped hierarchical porous carbon by chemical pre-activation combined with physical re-activation was proposed.The main research contents are as follows:（1）The activation effects of KOH,Na OH,Zn Cl₂,K₂CO₃,and CO₂ were investigated using PANI as the precursor.（2）The nitrogen-doped hierarchical porous carbon materials were prepared by K₂CO₃（or Na OH+K₂CO₃）chemical pre-activation combined with CO₂ physical re-activation to expand the pores,and their structures were characterized,and their electrochemical properties were tested in 6 M KOH aqueous electrolyte and DLC 3702organic electrolyte,and compared with commercial activated carbon YP-50F.The results show that hybrid activation of PANI carbonization product PBC by K₂CO₃and CO₂ is an effective method to prepare in situ nitrogen-doped hierarchical porous carbon.The nitrogen-doped hierarchical porous carbon PBC64 based on PANI prepared by K₂CO₃chemical pre-activation combined with CO₂ physical re-activation has a specific surface area of 1791.69 m²·g^-1,a pore volume of 0.99 cm³·g^-1 and a mesoporosity of 24.3%,and its conductivity reaches 230 S·m^-1 at 4 MPa.In the aqueous electrolyte 6 M KOH,when the current density is 0.5 A·g^-1,PBC64 exhibited a specific capacitance of 191 F·g^-1,which was higher than that of YP-50F at 143 F·g^-1.In the organic electrolyte DLC 3702,when the current density is 1 A·g^-1,PBC64 exhibited a specific capacitance of 132 F·g^-1 and an energy density of 41.25 Wh·kg^-1.The specific capacitance and energy density of YP-50F are98 F·g^-1 and 30.63 Wh·kg^-1 respectively under the same test conditions,and the storage capacity of PBC64 is 34.7%higher than that of YP-50F.Meanwhile,in the DLC 3702 system,PBC64 maintains 89.4%of its initial capacity after 10,000 cycles of charging and discharging at a current density of 1 A·g^-1 in the voltage range of 0～3 V,it has good cycling performance.The above results indicate that the nitrogen-doped hierarchical porous carbon prepared based on PANI hybrid activation is a supercapacitor electrode material with great potential for application.