Structure Design And Electrochemical Properties Of Activated Carbon Composite Electrode Materials Based On Waste Fiberboard

Carbon materials with the advantages of wide sources,low price,various forms and easy processing have been used in supercapacitors exhibiting excellent cycle stability,rate performance and becoming the most widely used energy storage materials.However,the storage capacity of is low due to the en ergy storage mode of carbon material is electric double layer.In this paper,the waste fiberboard containing12%urea formaldehyde resin is used as precursor to prepare negative nitrogen porous activated carbon through carbonization and activation.On this basis,the modified or loaded metal based pseudocapacitor materials is used to explore its structure regulation mechanism and electrochemical performance.The main results of the work are summarized as follows:(1)The N?S co-doped activated carbon is prepared by carbonization activation method.Sulfur as sulfur source.S is doped into carbon skeleton leading to the structural deformation of carbon material and enhance its electronegativity,hydrophilicity and surface utilization,resulting in edge defects due to the sulfur atom has a large atomic radius relative to carbon atom.At 0.05 Ag^-1,the specific capacitance of sulfur nitrogen co-loaded activated carbon electrode is 265 Fg^-1 that has increased by 17.3%.Low dimensional materials(mxene or graphene)were compounded with acid activated carbon by vacuum filtration.Low dimensional materials have the functions of conducting,bonding and substrate.Acid activated carbon is firmly anchored between the layers of low dimensional materials through its surface functional groups,which increases the layer spacing of low dimensional materials and forms a three-dimensional conductive network.In the case of no adhesive,flexible and compact electrode materials are prepared to avoid the addition of adhesive,and improve the energy density and conductivity of composite electrode materials cycle performance and rate performance.(2)Based on the realization of carbon based composite electric double layer energy storage,Mn O2with high theoretical specific capacitance was grown on the surface of graphene/acid activated carbon.3D sandwich structure is formed.At 0.05 Ag^-1,the specific capacitance of it is 378 Fg^-1.Co3O4 with structural stability was grown on the surface of graphene/acid activated carbon composite.The specific capacitance of Co3O4/graphene/acid activated carbon composite was 564 Fg^-1 at 0.05 Ag^-1.(3)In order to further improve the electrochemical performance of carbon-metal matrix composite electrode materials,nickel cobalt bimetallic selenide is compounded with acid activated carbon by hydrothermal method.The bimetallic selenide is directly grown on the surface of acid activated carbon with interpenetrating structure.Used as electrode material,it showed high specific capacitance and energy density.When the current density is 0.5 Ag^-1,the specific capacitance of the composite electrode is 1394Fg^-1.In order to further improve the cycle stability and rate performance of bimetallic selenide/activated carbon composites,tannin is used as a bridge to form a glue like nitrogen oxide layer between the metal selenide and negative nitrogen activated carbon.When the current density is 0.5 Ag^-1,the specific capacitance of the composite electrode is as high as 1262 Fg^-1.The asymmetric supercapacitor was assembled by using tannin modified nickel cobalt selenide/activated carbon composite as cathode.After10000 cycles,the specific capacitance still reached 97.35%of the initial value.(4)In order to further improve the electrochemical activity of carbon-metal matrix composite electrode materials,single metal Pd is doped on the surface of metal organic framework through hydrothermal and liquid phase,respectively.And is applied to energy storage and electrochemical detection to specifically recognize H2O2.Pd modified metal organic framework/acid activated carbon composite to modify glassy carbon electrode showes excellent electrochemical performance with detection range of 10?M-10.2 m M and 2?M-17.5 m M.When the current density was 5 Ag^-1,the capacitance retention of the composite was 83.579%and 78.313%,respectively.(5)Ni,Mo bimetallic and metal organic frameworks with high catalytic performance is fabricated to prepare metal organic frameworks/acid activated carbons through hydrothermal and liquid phase methods for energy storage and specific recognition of H2O2.At 0.5 Ag^-1,the specific capacitances of Ni and Mo modified metal organic frameworks/acid activated carbons composite electrodes are 1178.2 Fg^-1 and1135.7 Fg^-1,respectively.The sensitivity of metal organic framework/acid activated carbons for specific recognition of H2O2 was 0.277?A?M^-1 cm^-2 and 0.188?A?M^-1 cm^-2,respectively,and the detection limit was 0.185?M and 0.303?M,respectively.