Study On Synthesis Of Hierarchical Porous Advanced Carbon Materials And Its Electric Double Layer Capacitor Performance

Supercapacitor（SC）as a novel energy storage device exhibits a superior power density(¹0kWkg^-1),an excellent rate capability,a long cycle life（over 10⁶ cycles）,wide operating temperature range and high safe efficiency.These advantages make SCs suitable for use as auxiliary power for hybrid electric vehicle systems,uninterruptible power for computers,and electrical power system,memory backup systems and cold-starting assistants.So far the most widely used and commercialized SC electrode material is still carbon material.Carbon material with wide availability,cheap,large surface area and adjustable pore size has triggered research interests.This work strives to explore a simple,practicable and economical method for the preparation of excellent electrode material,hope for find broad commercial application in SCs.Our research work is showing as follows:One-pot and soft-template method was employed for synthesize a conducting polymer,poly-N-phenylethanolamine（PNPEA）which taking N-phenylethanolamine as the N-rich precursor.Next,carbonization and activation of PNPEA resulted in a series of porous N-doped carbon materials.the as-obtained N-doped carbon materials were confirmed by the systematic structure characterizations such as BET,scanning electron microscopy,transition electron microscopy,Raman spectroscopy,infrared spectrum,X-ray diffraction and X-ray photoelectron spectroscopy.Results indicate that the obtained sample at 800℃ presents peanut-shell-like configuration with abundant micro-mesopores and the surface area is high to 3103m²g^-1.At a current density of 1Ag^-1,the sample exhibits the specific capacitance of 356Fg^-1,good cycle stability and high power density in 1 mol L-1 H₂SO₄,which is superior to commercially available activated carbon.Three-dimensional（3D）interconnected porous nitrogen-doped carbon aerogels（CA）have been successfully prepared by self-template method.Polyvinyl alcohol and nitrogen-containing N-phenylethanolamine were taking as precursors,and boric acid as both crosslinking agent and self-template,the backbone is PVA-borate-PNPEA group formed by intramolecular dehydration between borate ion [B（OH）₄^-1],hydroxyl group of PVA or PNPEA,and experiences freeze-drying,carbonization and activation processes.Results indicated that,the CA with features like hierarchical porous structure,large effective specific surface area(2016 m²g^-1),nitrogen doping and superhydrophilic.The easily tractable,universal and cost-effective strategy together with the excellent performance in our case guarantees the large-scale application of the as-prepared activated CAs in SCs.The amorphous porous carbon materials were prepared by a one-step based on low cost and available raw materials Semen Cassiae as carbon and nitrogen source.By regulating the activator（potassium oxalate）proportion and temperature,the optimal conditions for preparation the sample are: the mass ratio of Semen Cassiae and potassium oxalate is 1:3,calcining temperature is 700℃,A series of structure analysis and electrochemical analysis technique had carried on the porous carbon materials to research the amorphous structure and electrochemical properties.Analysis results indicate that the biomass –based carbon materials with high specific surface area and reasonable pore size distribution,nitrogen heteroatom doping,high specific capacitance,good cycle stability and high power density and energy density.