Preparation,characterization,and Applications Of Aniline Polymer And Composite In Electrochemical Devices

Poly Aniline（PANI）,a well-known conducting polymer,has undergone extensive research over the last 40 years.Now,one of the most fascinating and difficult tasks is to modify PANI in order to improve their performance.In this study,Poly-2-Amino-Benzonitrile（PABN）and a PANI/La₂O₃ composite were prepared,and their performance in electrochemical sensors and electrochemical energy storage was investigated.First,PABN which has nitrile group attached on o-position of benzene ring were prepared,and copolymer of aniline and 2-Amino-Benzonitrile（ABN）at different monomer feed ratio were also prepared.The obtained products were characterized by Scanning Electron Microscope（SEM）,Brunauer-Emmett-Teller（BET）and Barrett-Joyner-Halenda（BJH）,etc.Furthermore,p H sensors were assembled with the obtained products,and the obtained sensors were characterized by open circuit potential method with the two-electrode system.The experimental results demonstrate that the sensitivity parameters of the obtained PABN sensors are very close to the Nernstian theory value at-52 m V/p H in the p H range of 1 to 13 in phosphate buffers.The experimental results also show that the PABN p H sensor has high performance in potential fluctuation,deviation,drift,and hysteresis.The excellent reversibility,repeatability,longtime stability and the ion selectivity of PABN p H sensor made it suitable in practical applications.PABN,has wide redox potential window（-0.2 to 0.8 V）,should has superior performance to PANI used as supercapacitor electrode materials.Here,Cyclic Voltammetry（CV）,Electrochemical Impedance Spectra（EIS）,and Galvanostatic Charge Discharge（GCD）were used to characterize the constructed PABN electrode.The specific capacitance of PABN is 171 F/g at 1 m Vs^-1.Over 3000 cycles,the cyclic stability and specific energy were well preserved,indicating a significant energy storage electrode material.Second,composite of PANI/La₂O₃ were prepared and the corresponding supercapacitors were assembled.The obtained composites were characterized by SEM,Energy Dispersive X-ray Spectroscopy（EDX）,Fourier Transform Infrared Spectroscopy（FTIR）,UV–Visible Spectroscopy（UV-Vis）and X-Ray Photoelectron Spectroscopy（XPS）,etc.The assembled supercapacitors were tested by CV,EIS,and GCD.At a scan rate of 5 m Vs^-1,the PANI/La₂O₃ composite electrode possesses specific capacitance of 718 F/g and a specific energy of 53.8 Wh/Kg.At a high current density of 10 A/g,the electrode retains a significant amount of its power throughout.The experimental results demonstrate that composite PANI/La₂O₃electrode has a higher capacitance when mass is loaded heavily.