Research On The Macro-fabrication Process Of Flexible Nanocarbon-based Electrodes For Supercapacitors

Due to the merits of superior conductivity,high strength and high specific surface area,carbon nanofibers(CNFs)and graphene,have been widely used in electrode materials,composite materials and other fields.Therefore,it is of great significance to develop a kind of carbon nanofibers which can be continuously prepared for commercial production.However,the two-dimensional(2D)graphene tends to aggregation,which influences its properties.In many reports,preparing threedimentional(3D)graphene is an effective method to solve above issue.Meanwhile,rational design of free-standing 3D porous graphene films with controllable pore size distribution is significant to meet high widely application.In the dissertation,we firstly prepared a large area of carbon nanofibers on Cu foil continuously by CVD method;Then,a high quality and nanoporous graphene film grown on sandwich nanoporous copper,which was prepared by dealloying Cu Mn-CuCu Mn alloy.The main conclusions are as follows:(1)A large area of carbon nanofibers was continuously prepared on copper foil.When the power of plasma treatment was 40W,uniform distribution and high purity CNFs with a diameter of 50nm?60nm were achieved.With the increase of catalyst concentration,the growth temperature could be effectively reduced;Increasing gas flow,CNFs changed from straight to double helix,then to single helix and straight wall;With the increasement of temperature,the diameter of CNFs gradually changes from straight wall to single helix.At high gas flow rate,the diameter of CNFs increases apparently,and then changes from single helix to straight wall,until to single helix and straight wall;when the temperature is reduced from 600?-550?-550?,uniform distribution,large helix angle and high purity can be generated Single helix CNFs.(2)Nanoporous copper(NPC)sandwiched between Cu was prepared by dealloying CuMn-Cu-CuMn.With the increasing of thickness,the pore diameter of nano porous copper increased firstly and then decreased to 30nm in 0.2M HCl;As the alloy thickness was 200?m,the pore diameter of nano porous copper can decrease during increasing concentration,and the size of skeleton increased first and then decreased.(3)The high quality and nanoporous graphene was prepared by CVD method,with the sandwich nano porous copper as the matrix.And the pore and skeleton size of the sandwiched nano-porous copper increased significantly.When the thickness of copper and manganese is 200?m,the flow rate of acetylene should not be too large,and the deposition time of hydrogenated graphite should not be too long.Among them,the quality of graphene is not high when C2H2:H2:ar=5:200:500 gas flow is introduced at 300?,hydrogenated graphite is deposited for 10 min,and then heated to 800 ?,the sample is cracked for 1-10min;With the increasement of alloy thickness,the quality of graphene increases first and then decreases.And the quality of graphene is better;at alloy thickness was 550?m?...