Research On Conductive Polymer Matrix Composites And Application In Flexible Energy Devices

The rapid development of flexible smart electronics is placing greater demands on energy storage devices.The design of energy storage devices is not only aimed at increasing the electrical capacity,but also requires flexible features such as bendability,foldability and stretchability.Research into lightweight and flexible electrode materials with excellent electrochemical properties is key to the design of flexible energy storage devices.This paper focuses on new high-performance electrode materials based on conductive polymers for the assembly of flexible energy devices,mainly flexible supercapacitors.This thesis provides positive guidance on how to design and fabricate conductive polymer-based composite electrode materials and how to carry out research on their application in flexible energy storage devices.The main research is divided into the following three areas:(1)Four different conductive polypyrrole derivative films were designed and synthesised based on pyrrole derivatives containing different functional groups(1-methylpyrrole,1-aminopyrrole,methyl 1H-pyrrole-3-carboxylate and 1-benzylpyrrole)using an electrochemical polymerisation method.The rigid conjugated structure of the polypyrrole derivatives results in poor mechanical properties of the films,which do not meet the requirements of self-supporting electrodes.By adding polyols as dopants and improving the preparation method,we have synthesised flexible polyol-polypyrrole derivatives with a dynamic network structure using hydrogen bonding and electrostatic interactions between the polyol and the polypyrrole derivatives,and analysed the effect of the dopants on the electrical conductivity of the materials.(2)Flexible supercapacitors are important in the field of energy storage,and while satisfying high specific capacitance,the stretchability of the device is crucial for its application in flexible electronics.Here,we investigate a highly stretchable hydrogel electrode.Two materials,polyvinyl alcohol(PVA)and polyacrylamide(PAAm),were blended as a flexible substrate for the hydrogel electrode and then combined with poly(3,4-ethylenedioxythiophene): polystyrene sulfonate(PEDOT: PSS)to obtain the conductivity and electrochemical properties of the hydrogel material.Using PVA hydrogels as electrolytes to construct fully solid-state flexible supercapacitors with a sandwich structure,it has high quality capacitance(130 F/g),good flexibility and electrochemical stability,and these excellent overall properties indicate that it has the potential to be used in a new generation of flexible energy storage devices.This work paves the way for potential applications in electronic skins,electronic fabrics and electronic bracelets.(3)In this work,we first successfully synthesized polyvinyl alcoholpolyacrylamide(PVA/PAAm)composite hydrogels and mixed them with aniline(PANI)monomer and 3-aminophenylboronic acid hydrochloride(ABA)to form the final flexible conductive hydrogels in the presence of conventional crosslinkers and initiators,which are a good self-supporting electrode material.Tested by electrochemical means,it exhibits high volumetric specific capacitance(102 F/g),high mechanical strength(tensile stress of 5.4 MPa),good flexibility(elongation at break of150%)and electrochemical stability under a three-electrode system.The excellent overall performance of this electrode material indicates that it can be used as an electrode material for flexible supercapacitors.