| In order to realize the sustainable development of mankind,we must constantly optimize the energy structure.New energy technologies emerge at the historic moment,among which supercapacitor,as a high-power energy storage device,is one of the most promising new energy storage devices.Is the core of the super capacitor energy storage electrode materials,polypyrrole is known among the numerous candidate material,it has high theoretical capacity and synthesis is simple,low cost,very suitable for as a high-performance device of electrode materials,however,the material in the discharge and recharge cycles,with the phenomenon of volume contraction and expansion,the short cycle life.In this paper,several graphene/polypyrrole composite active materials with different structures and morphologies were prepared by introducing graphene and using electrochemical deposition strategy.The relationship between the structure and morphology of composite electrode materials and electrochemical performance was studied.The main contents and results are as follows:1.Using the scheme of electrochemical intercalation,high quality graphene powder materials were prepared simply and quickly.Graphene/polypyrrole electrode materials with three-dimensional crosslinked porous structure were directly synthesized on carbon cloth by electrochemical co-deposition strategy.The influence of the content of graphene on the morphology and structure of the composite electrode material was studied by adjusting the content of graphene in the mixture.When the graphene is 0.1 mg ml-1,the area specific capacity of the composite is as high as 580.75 m F cm-2,and the capacity retention is 83.03%when the discharge current density is increased from 1 m A cm-2 to 10m A cm-2.2.From the electrochemical intercalating inspired by stripping the preparation of graphene powders,two phase equilibrium through regulating the graphene/graphite,break through the traditional"top-down,bottom-up"graphite and graphene oxide-graphene electrode"lengthy graphene electrode preparation method and the high cost,realize the direct preparation of graphene from graphite pieces/graphite electrode.In situ composite polypyrrole was directly deposited by electrochemical deposition to form a unique"bowl"structure.The mechanism of the formation of"bowl"structure was discussed by controlling the deposition time.Preparation to turn it into a solid-super-capacitors,not only the capacity is good,up to 373.2 m F cm-2(The test conditions:0.5m A cm-2.),and excellent cycle stability(10,000 times cycles can still maintain the initial96.8%)and better performance of ratio(by 0.5 m A cm-2 to 10 times,76.5%of the capacity to maintain the initial),in addition,the device has good flexibility,can work under the condition of bending.3.In the last chapter basal material found in the process of preparation of graphite side formed orderly the pages of layered porous structure,this structure on the one hand for ion and transmission,at the same time,on the other hand,the structure can further enhance the specific surface area of the electrode materials and to provide more active site to composite with other materials.Inspired by this,the graphite sheet was cut into graphite strips,and the graphene strips were obtained by adjusting the voltage and stripping intercalation time.The graphene/polypyrrole electrode material with three-dimensional layered structure was synthesized by a similar scheme,and the effect of deposition time on the rate performance was mainly discussed. |
PDF Full Text Request