Polyaniline And Its Composite Materials Preparation And Supercapacitor Performance Research

Supercapacitors are widely investigated owing to safety,high specific capacitance,high-power density,long cyclic-life,wide working temperature range and good environmental friendly.Polyaniline?PANI?was widely applied in supercapacitor due to large specific surface area,high theoretical capacitance,low cost and good environmental stability.However,PANI is limited in supercapacitors by the poor rate performance,low cycles stability and the morphology and structure.In this paper,in order to enhance the electrochemical performance and obtain the uniform morphology of PANI,PANI was prepared by oxidative polymerization of microemulsion,and ACF/PANI composites were synthesized by in-situ oxidation polymerization,ACC/PANI and ACC/MnO₂/PANI composites were constructed by electrodeposition through consulting literature material.The surface morphology,physical characteristics,structural characterization and electrochemical performance of the prepared samples are conducted.The main conclusions are as follows:?1?PANI with nanotubular morphology was synthesized by soft template method and the soft template formed by micelle of surfactant CTAB and reaction lasts for 12 hours at 10?and n _An:n _CTAB=4:1.Due the large specific surface area and a good charge transfer path,the specific capacitance of nanotubular PANI was 426.9 F·g^-1 at 0.5 A·g^-1 and the capacitance retention rate is 87.5%after 2 000 cycles.?2?ACF/PANI and ACC/PANI composites were separately prepared on ACF and ACC substrate by in-situ polymerization with m _An:m _ACF=2:1 and electrodeposited in An and H₂SO₄ mixed solution.The results showed that ACF/PANI and ACC/PANI were coating structure.Attributing to the excellent conductivity of carbon materials and the uniform structure of PANI layer,the specific capacitances of ACF/PANI and ACC/PANI reach up to 525.0 F·g^-1 and 477.8 F·g^-1,and the capacitance retention rate were respectively 85.69%and 83.9%after 2 000 cycles,while the preparation process of ACC/PANI was simple and rate capability was better than that of ACF/PANI.?3?ACC/MnO₂/PANI ternary coaxial composite was fabricated on ACC/MnO₂ matrix by electrodeposition in An and H₂SO₄ mixed solution.The results showed that ACC/MnO₂/PANI was coaxial structure,and the specific capacitance of ACC/MnO₂/PANI was as high as 728.7 F·g^-1 and the capacitance retention rate reachs up to 87%after 2 000 cycless due to the synergistic effect and the high ability of charge transportation.?4?Symmetrical ACC/MnO₂/PANI//ACC/MnO₂/PANI supercapacitor was assembled with Na₂SO₄ as electrolyte and ACC/MnO₂/PANI as positive and negative electrodes.The specific capacitance of the single supercapacitor was 281.3 F·g^-1,and 3 ones in series supercapacitors could light up the LED with 1.8 V.