Synthesis And Applications In Energy Storage Devices Of Conductive Polymers And Their Composites

Since the Industrial Revolution,people's demand for traditional fossil fuels has been increasing,but the fossil fuel resources on the earth are limited and non-renewable.Therefore,In recent years,the development of renewable energy sources?such as solar energy,wind energy,geothermal energy,tidal energy and biofuels?has attracted attention in different countries around the world.With the exception of biofuels,most renewable energy is provided in the form of electricity.Therefore,there is an urgent need for reliable electrochemical energy storage platform,including batteries and supercapacitors.This paper mainly introduces the preparation of binary or ternary composites of conductive polymers and graphene or bimetallic hydroxides and conductive polymer copolymers by electrochemical or chemical processes,and their applications in supercapacitors and zinc rechargeable battery electrode materials by electrochemical methods.Here are the main contents:1.First,the modified Hummers method was used to prepare graphene oxide,and then cyclic voltammetry was used to prepare reduced graphene oxide/polyazurine B?r GO/PAB?binary composites via one step electrochemical reduction/polymerization.After a series of characterization and analysis of the material,the electrochemical performance of r GO/PAB composite as the electrode material of supercapacitor was tested by Cyclic voltammetry?CV?,constant current charge and discharge?GCD?and electrochemical impedance technology?EIS?.The results show that when the current density is 0.5 A g^-1,the specific capacity of r GO/PAB reaches 537.2 F g^-1,and at a current density of 10 A g^-1,the specific capacity can reach 417.5 F g^-1.In addition,under the current density of 0.5 A g^-1 for 1000 cycles,the composite material can still maintain the original specific capacitance of 90.9%.2.The two-step synthesis process was used to prepare reduced graphene oxide/poly?azure B?/nickel hydroxide?r GO/PAB/Ni?OH?2?ternary composite materials.First,graphene oxide/poly?azure B??GO/PAB?was prepared by chemical polymerization.Then,r GO/PAB/Ni?OH?2 was prepared in an autoclave at 180°C by hydrothermal method,and graphene oxide was reduced at high temperature.The surface morphology and structure of ternary nanocomposites were characterized and analyzed.At the same time,the electrochemical performance of the ternary nanocomposite as an electrode material for supercapacitors was studied by CV,GCD and EIS.The test results show that compared with other control electrode materials,r GO/PAB/Ni?OH?2-20 exhibits the best electrochemical performance.When the current density is 1 A g^-1,the specific capacity is as high as 2642F g^-1,and the cycle retention rate reaches 98%under the condition of 2,000 cycles of charge and discharge.The main reason why the ternary composites can show good electrochemical performance is the good synergy between r GO,Ni?OH?2 and PAB.3.Using cyclic voltammetry,aniline was mixed with thionine monomers with different concentrations to obtain copolymer poly?aniline-thionine??PANTHI?by one-step electrochemical copolymerization.The successful synthesis of PANTHI was verified by a series of characterization methods.The electrochemical properties of the obtained copolymers were investigated by CV,EIS,and GCD.The results showed that compared with 2 mmol L^-1 and 6 mmol L^-1 thionine,the copolymer obtained by 4mmol L^-1thionine and aniline had better electrochemical activity.The obtained zinc-PANTHI battery can maintain high electrical activity at high p H?4.8?.When the current density is 200 m A g^-1,it can reach a specific capacity of 157.8 Ah kg^-1 and a capacity density of 173.6 Wh kg^-1.At a current density of 200 m A g^-1and 200 cycles of charge and discharge,the battery's specific discharge capacity decreases to 120.3Ah kg^-1,but the Coulomb efficiency remains at 95.3%.These results show that,although the electrochemical activity decreases slightly with the increase in the number of cycles,the secondary battery still has good charge and discharge performance and is very promising as an electrode material for zinc rechargeable batteries.