Preparation And Characterization Of Carbon-based Supercapacitor

Supercapacitors have become a hotspot in recent years because of its high power density,good cycle stability,fast charging and discharging rate.Compared with traditional capacitors,supercapacitors have higher energy density.Compared with batteries,the supercapacitors have higher power density.So supercapacitors can make up for the gap between battery and traditional capacitor gap.In this paper,we against the problems,such as:the specific capacitance of supercapacitors is not high,the electrode materials are mostly powder,the voltage range of supercapacitors is too small and how to choose the electrolyte solution,do a research.The main results and conclusions are summarized as follows:?1?Pure graphene gel due to the interaction between?-?bonds and reduced graphene oxide?abbreviate rGO?sheets,the specific surface area is greatly decreased,and its strength is small,which greatly limits its application in supercapacitors.So,we added Polyaniline?abbreviate PANI?,which can increase the strength of the obtained rGO/PANI gel,and improve the electrochemical performance of the gel.The r GO/PANI gel we prepared has a specific capacitance up to 257F/g and can withstand more than 1000 times its weight without deformation.?2?Powder materials have various problems because it needs to be re-processed.Therefore,we prepared the rGO/PPy tube film by mixing the reduced graphene oxide with the polypyrrole?abbreviate PPy?tube.The prepared rGO/PPy film has excellent electrical conductivity,bending strength,electrochemical performance.The specific capacitance of the rGO/PPy film was 161.4F/g,and the specific capacitance of the all-solid symmetrical supercapacitor was 155F/g.?3?The working voltage range of aqueous symmetrical supercapacitors is generally not more than 1V,which limit its application.We prepared the rGO/N-CNT film by mixing the reduced graphene oxide with the Nitrogen doped carbon nanotubes?abbreviate N-CNT?.rGO/N-CNT film and rGO/PPy tube film were assembled into asymmetric supercapacitor,which the working voltage increased to 1.3V,and the capacitance has49.3F/g.The rGO/N-CNT film has the advantage of the rGO/PPy tube film.In addition,the rGO/N-CNT film has higher stability and larger suitable current densities.Its specific capacitance reached 120.4F/g,and when the current density change from 20A/g to 0.5A/g,the capacitance retention rate of 71.4%.?4?The effect of different electrolyte solution on the electrode material is different.We prepared reduced graphene oxide/polypyrrole tube/chitosan?abbreviate Cs?aerogels with good compression recovery performance.When the compression rate was over 80%,the recovery rate was as high as 95.83%.When using 1M H₂SO₄ as the electrolyte,the specific capacitance of rGO/PPy/Cs120 is 89.6F/g at 0.5A/g.When using 1M Na₂SO₄ as electrolyte,the specific capacitance only 73.8F/g.