Synthesis of advanced polyaniline derived hybrid materials for an electrode material of pseudo-supercapacitors

Abstract

In this research, an electroactive polyaniline based hybrid materials for pseudosupercapacitors was synthesized by adjusting oxidation and protonation degree. A new electrode structure was designed by in situ deposition of the nanostructured PANI on carbon fibrous paper, which shows a significantly enhanced capacitor performance. Through cyclic voltammetry and charge-storage analysis, capacitor performance and charge-storage mechanisms were obtained and discussed. 1. Polyaniline nanowires were obtained by a facile chemical oxidation method, which largely increased specific capacitance due to their large surface area and sound electric conductivity. 2. Bimetal oxide nanoparticles (NiFe2O4 and MnFe2O4) were synthesized by hydrothermal method. Different hybrid materials were obtained via compositing the as prepared oxides with polyanilne. 3. Through in-situ deposition of polyaniline on carbon paper, a fuzzy polyaniline layer was grown on 3-D carbon fiber web, where polyaniline nanowires were grown on this fuzzy layer. Therefore an electrode with relatively more electro active materials and smaller series resistance was obtained, which can be applied to various flexible device. 4. Cyclic voltammograms and charge-discharge curves were obtained with three electrode system and analyzed combining with electric equivalent circuit. Specific capacitance of 174F/g was calculated from charge-discharge curves. This value may be ascribed to the sound effective electric contact between polyaniline and carbon fiber, large surface area of nanowires, and highly electro active polyaniline. 5. With cyclic voltammograms and simplified redox reaction among polyaniline, charge-storage mechanism was tentatively proposed and analyzed. Other polyaniline derived hybrid materials like polyaniline & graphene, polyaniline & CNT can be easily achieved with similar synthesis method.