Study On Preparation And Performance Of Flexible Supercapacitor

The supercapacitors as a new-style energy storage device have attracted tremendous attention.But unstable interface between the electrodes limits the development of flexible supercapacitor,it's promising to prepare a electrode with stable interface.In this work,the carbon materials are prepared as the buffer layer to depress the interface stress,MnO₂ as the active material to assemble flexible supercapacitors.The detailed research contents are as follows:?1?Composite structure of PCF/Ni is fabricated by CVD method.Then MnO₂ film is grown on the PCF/Ni by using an improved chemical bath deposition.The PCF serves as a buffer layer providing an convenient way to deposite MnO₂ film tightly on PCF/Ni to fabricate the stable MnO₂/PCF/Ni electrode.Microstructure observations show that the MnO₂ film has a hierarchically porous structure,which provides a large surface area for charge storage.The FSC based on MnO₂/PCF/Ni electrode exhibits high-energy/power density,ultrahigh rate capability,wide frequency range,extraordinary flexibility,and superior cycle lifetime.Furthermore,the FSC has a very short time constant?0.3-0.5 ms?and exhibits minimal change in capacitance under dynamic bending.?2?We choose the nickel wire as the other flexible substrate to prepare muliti-layer garphene?MGr?/Ni structure by CVD.Then MnO₂ was deposited on the MGr by ICBD to fabricate the MnO₂/MGr/Ni electrode,in which the muliti-layer garphene?MGr?serves as a buffer layer to facilitate the loading of the MnO₂ and reduce the interfacial stress.Thus,the wire-type MnO₂/MGr/Ni electrode has a stable and high quality interface.The wire-type supercapacitor?WSC?based on wire-type MnO₂/MGr/Ni electrode exhibits good electrochemical performance,high rate capability,extraordinary flexibility.Furthermore,the FSC exhibits minimal change in capacitance under different bending shapes.