Preparation And Electrochemical Properties Of PEDOT:PSS/GO/CMC Flexible Composite Electrode

Compared with conventional energy storage device,flexible supercapacitor has good application prospects in the development of energy equipment for biomedicine,portable wearable electronic device,new energy vehicles,intelligent packaging because of its good electrochemical performance and mechanical flexibility.The performance of the supercapacitor depends greatly on the electrodes.Different from traditional electrodes,flexible electrodes must have high flexibility and stability.At present,common electrode materials of flexible supercapacitors have some problems,such as poor chemical stability,short service life and environmental pollution.Therefore,the development of a low cost,high cost performance,environmental friendly highperformance flexible electrode material is a significant research orientation.On the basis of the research background mentioned above,carboxymethyl cellulose,a renewable biomass material with abundant sources,is used as the matrix to prepare graphene oxide(GO)/carboxymethyl cellulose(CMC)binary composite flexible electrode and PEDOT:PSS/GO/CMC ternary flexible electrode in this paper,and the ternary flexible electrode is used to the assemble flexible all-solid supercapacitors simultaneously.The electrochemical performance of composite electrode and flexible supercapacitor were analyzed and explored.The main research contents and results are as follows:GO/CMC binary composite flexible electrodes with different mass ratios were prepared by ultrasonic dispersion and vacuum filtration.The effects of different rations of GO and CMC on the electrochemical properties of composite thin film electrodes were imvestigated.When the mass ratio of CMC and GO was 1:4,the GO/CMC binary composite film electrode presented the best electrochemistry performance,and the area specific capacitance was 568.5 mF/cm~2.Moreover,the RGO/CMC binary composite film electrode was prepared by using HI reduction GO/CMC with the optimal mass ratio.The specific capacitance of RGO/CMC was 175 mF/cm~2,which is lower than that of GO/CMC.Although this reduction method can well prevent RGO agglomeration,further exploration is needed to improve the electrochemical performance.PEDOT:PSS/GO/CMC ternary composite flexible electrode with different mass ratios were prepared by ultrasonic dispersion and vacuum filtration on the basis of the optimization of electrochemical performance of GO/CMC binary composite thin film electrodes.The effects of different rations of PEDOT:PSS,GO and CMC on the electrochemical properties of composite thin film electrodes were investigated.The prepared PEDOT:PSS/GO/CMC ternary film electrode exhibit the best electrochemical performance when the mass ratio of CMC:GO:(PEDOT:PSS)was 1:4:8,and the area specific capacitance was 682 mF/cm~2.The electrochemical performance of PEDOT:PSS/GO/CMC ternary composite thin film electrode was obviously better than that of binary composite thin film electrode,which proves that the electrochemical performance of materials can be significantly improved by the combination of PEDOT:PSS and GO/CMC.Based on the optimization of electrochemical performance of PEDOT:PSS/GO/CMC ternary composite film electrode which were selected as positive and negative electrodes,and PVA-KOH was used as solid state electrolyte to assemble a sandwich structure of flexible symmetric all-solid-state supercapacitor.and its electrochemical stability was investigated.The results showed that the maximum area specific capacitance of flexible supercapacitor was 108.5 mF/cm~2,and 79%of the initial specific capacitance could be maintained after 2000 cycles.Furthermore,after bending at different angles of 0°,45°,90°,135° and 180°,the electrochemical performance remained basically unchanged,and the initial specific capacitance was still 92%after repeated bending 200 times,showing good flexibility and electrochemical stability.