N-Doped Activated Carbons Derived From Amygdalus Pedunculata Shell For Supercapacitors

Nowadays,severe consumption of fossil energy and serious environmental pollution.,it is an urgent problem for people to develop efficient and clean energy storage devices.As a new energy storage device,supercapacitors have many advantages,such as high storage capacity,short charging time,long discharging time,and high power transmission in a short time.However,the disadvantages of low energy density for supercapacitors are increasingly apparent.How to improve the capacitance and energy density of supercapacitors is the difficulty and focus of supercapacitor research.Due to high specific surface area,developed pore structure,low price and high yield,porous activated carbon is widely used as an electrode material for supercapacitors.Additionally,the capacitance of the supercapacitor could be improved by doping heteroatoms and increasing specific surface area in activated carbon.Amygdalus pedunculata Pall seed shells?APS?is the fruit shell of Amygdalus pedunculata Pall?AP?seed.Its main components are cellulose,hemicellulose and lignin.It has a hard texture and a large yield.In this experiment,nitrogen-doped porous activated carbon with different pore structures was prepared by using almond shell as raw material and potassium hydroxide as activator.The surface morphology,pore structure and chemical composition of the nitrogen-doped activated carbon were analyzed.The capacitance performance of porous activated carbon was studied using 6 M KOH as the electrolyte.The specific researchs are as following:?1?APS/PANI composite with high nitrogen content was prepared by growing polyaniline?PANI?on the surface of APS by in-situ polymerization method with APS as a matrix.Using KOH as the activator,porous activated carbon with larger specific surface area(2883 cm² g^-1)was prepared by changing the activation temperature and activation ratio to adjust the pore structure.In a three-electrode system,the specific capacitance can reach to329 F g^-1 at a current density of 0.5 A g^-1.In a two-electrode system,when the current density was 0.5 A g^-1,its specific capacitance can reach to 265 F g^-1,and energy density can obtain 36.8 W h kg^-1 at a power density of 150 W kg^-1.?2?Porous nitrogen doped Amygdalus pedunculata Pall seed shells/Polyacrylamide composites were prepared by in-situ polymerization.The nitrogen-doped porous activated carbon was prepared through high-temperature carbonization and KOH activation.The porous material displays a specific surface area of 1662 m² g^-1.In a three-electrode system,the specific capacitance can reach to 314 F g^-1 when the current density is 0.5 A g^-1,indicating that the as-prepared nitrogen doped porous activated carbon has better electrochemical properties.