One-dimensional Growth Of Polyaniline On Carbon Fiber Cloth And Its Pseudocapacitive Properties

In order to effectively initiate aniline (An) polymerization on carbon fiber cloth (CFC), the CFC was pretreated through ultrasonic and electrochemical treatment to afford ANEA with good hydrophilicity and electrochemical property. The pretreatment effect was studied by contact angle measurement, scanning electron microscopy (SEM) and cyclic voltammetry (CV). Then a piece of ANEA was first dipped into An solution containing H2SO4 to absorb the monomer. Then the polymerization was initiated in Ammonium persulfate (APS) and K2Cr207 solution, respectively. ANEA-PANI-APS and ANEA-PANI-K2Cr207 were prepared by repeating the above steps for several times. The morphologies of the polymers were investigated by SEM. Their vibrations were studied by fourier transform infrared spectroscopy (FT-IR). Pseudocapacitive properties of the products were studied by CV and galvanostatic charge/discharge (CP) experiments. It was found that the PANI in ANEA-PANI-APS existed in the form of nanofibers while the polymer in ANEA-PANI-K2Cr207 existed in nanoparticles, which illustrated that one-dimensional growth of PANI can be promoted by APS initiated polymerization. The nanofibrous structure enables the effect contact of the polymer with electrolyte to improve their electrochemical properties, ANEA-PANI-APS displayed a high specific capacitance of 644 F/g.The influence of concentrations of H2SO4 and APS on one-dimensional growth of PANI and its pseudocapacitive properties were also studied in this work. The morphologies of the polymers obtained under different polymerization conditions were observed by SEM, while the pseudocapacitive properties were studied by CV and CP. It was found that high-performance PANI nanofibers could be obtained when the concentrations of H2SO4 and APS were 0.2 and 0.05 mol/L respectively. The PANI nanofibers prepared under this condition distributed uniformly on surfaces of carbon fiber cloth, which was beneficial to the charge transfer between the polymer and the basal carbon fiber cloth. In order to study the application of the PANI in super capacitor, we assembled symmetrical model super capacitors of ANEA-PANI-APS//ANEA-PANI-APS and ANEA-PANI-K2Cr2O7//ANEA-PANI-K2Cr2O7 using ANEA-PANI-APS and ANEA-PANI-K2Cr2O7 as both of the positive and negative electrodes in 0.5 mol/L H2SO4 electrolyte, respectively. Their performances were studied by CV and CP.