Preparation And Performance Sepiolite/Polyaniline Nanocomposite Electrode For Supercapacitors

With the development of supercapacitor, the preparation and performance of electrode materials with high performance and low cost have been most actively investigated. Since polyaniline (PANi) offer the advantages of lower cost, excellent conductivy, easy preparation and good chemical stability, it has been paid much attention as electrode materials. Owing to its strong adsorption and high specific surface area, one-dimensional sepiolite (SEP) nanofiber has been combined with polyaniline to prepare sepiolite/polyaniline nanocomposite by in-situ chemical oxidative polymerization, and its structure and various properties have also been detailedly studied.Firstly, raw sepiolite fibers were treated with hydrochloric acid solution by orthogonal experiments, then the acid treated sepiolite (ASEP) was organic modified by3-triethoxysilylpropylamine (KH550) to get OSEP. FTIR、XRD、 FESEM、TG-DTG and BET analysis were employed to characterize the morphology, structure, thermal performance and specific surface area of the resulting sepiolite nanofibers.Secondly, one-dimensional core-shell sepiolite/polyaniline nanocomposites were synthesized by in-situ chemical oxidative polymerization. FESEM、conductivity analysis、FTIR、Raman spectra、UV-vis and XRD were conducted to characterize the morphology, structure and electrical properities of the OSEP/PANi nanocomposites. The results showed that polyaniline existed in nano-sized worm-like structure and was perpendicular to the sepiolite axis, and one-dimensional core-shell OSEP/PANi nanocomposites were formed. High degree of electron delocalization, electrical conductivity and good crystallinity could be achieved for OSEP/PANi nanocomposite.To investigate the electrochemical capacitance performance of OSEP/PANi nanocomposites as electrode materials for supercapacitor in acid electrolyte, cyclic voltammetry analysis (CV)> electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge analysis were adopted. The specific capacitance of OSEP/PANi-01is293F/g, which is about2times of pure PANi (134F/g) at the current density of1A/g in1M H2SO4electrolyte. Furthermore, the internal resistance of OSEP/PANi-01nanocomposite is0.6Ω which is smaller than pure PANi (1.6Ω).Finally, in order to investigate the electrochemical capacitance performance of OSEP/PANi-01and OSEP/PPy-01nanocomposites as electrode materials for supercapacitor in neutral electrolyte, CV、EIS and galvanostatic charge/discharge analysis were adopted. The results showed that OSEP/PANi-01had higher specific capacitance than OSEP/PPy-01nanocomposites, but it was more suitable for acidic electrolyte.