Preparation Of Pomelo Peel Biomass Carbon And Application Of Energy Storage Materials

As one of the most promising and environment friendly new energy storage devices,supercapacitors have many advantages including fast charging speed,long cycle life,high power density and high energy density so that widespread attention from people are attracted and the market scale is constantly expanding.The commonly used metal oxynitride and conductive polymer electrodes can provide high pseudocapacitance but poor cycle stability.Graphene and carbon nanotube electrodes of carbon materials are difficult to prepare and costly.Therefore,Large-scale production and application of supercapacitors are limited.So more and more researchers hope to develop new electrode materials.In this paper,pomelo peel was used as a carbon source precursor and low corrosive KCl solution was used as an activating agent.Under the protection of a nitrogen stream,solid block biomass porous carbon material was obtained by high temperature carbonization in a vacuum tube furnace.Its micro-morphology structure was charactered by specific surface area and porosity test(BET),scanning electron microscope(SEM)and X-ray photoelectron spectroscopy(XPS).The formation mechanism of the porous structure was analyzed according to the characterization of the micro-morphology structure.The electrochemical performance of pomelo peel biomass porous carbon and button-type symmetric supercapacitor were tested by cyclic voltammetry(CV),constant current charge and discharge(CP)and alternating current impedance(EIS).The research indicate that pomelo peel biomass porous carbon prepared after activation by KCl solution show high specific surface area(about 296 m2/g)and porosity(about 0.3 m3/g).At a current density of 1 A/g,the specific capacitance could reach 226 F/g,the power density could reach 236 W/Kg and the energy density could reach 28.2 Wh/Kg.The coin-type symmetric supercapacitor maintained 100%coulombic efficiency and 78%capacitance retention rate after 1000 charge and discharge cycles at a current density of 1 A/g which proved its excellent cycle stability.The as-prepared pomelo peel derived porous carbon showed green and low-cost carbon source precursors,simple synthesis methods and excellent electrochemical performance,indicating it would be a promising candidate for high-performance energy storage materials.