Solid-state Synthesis And Properties Of Polyaniline/Carbon Nano Tubes,TiO₂Composites

Among conducting polymers, polyaniline （PANI） has been used extensively inelectrochromic displays, electrocatalysis, rechargeable batteries, and sensors due to itshigh electrical conductivity, reversible electrochemical redox property, excellentcharge storage capacity and good environmental stability.Inorganic nanoparticles havebeen widely used in electronics, catalysis, biotechnology, optics, and medical sciencebecause of their excellent physical and chemical properties. Recently, it has becomean interesting research field that the preparation of superior performance of compositematerials which containing inorganic nanoparticles and PANI. In this paper, a seriesof PANI/inorganic nanoparticals composites prepared via solid-state synthesis methodwith the multi-walled carbon nanotubes （MCNTs）, single-walled carbon nanotubes（SWNTs）, anatase-TiO₂and rutile-TiO₂as an inorganic phase, respectively. FTIR,Raman, UV-vis, XRD, TEM, SEM and TGA were used to characterize the structureand morphology of composites. The electrochemical performances were investigatedby CV, galvanostatic charge–discharge curves and EIS measurments. The maincontents are summarized as follows:1．PANI/MCNTs composites with the MCNTs content of8wt%,16wt%,24wt%and32wt%were prepared by solid-state synthesis. The results showed that thecomposites display higher oxidation and doping degree, higher conductivity aswell as different morphologies in presence of MCNTs during the solid-statesynthesis. Galvanostatic charge–discharge measurements indicated that thecomposite with16wt%MCNTs had the highest specific capacitance, and itscapacitance reach to522Fg-1and425Fg-1in1M H2SO4and1M KCl electrolyte,respectively.2．PANI/SWNTs composites with the SWNTs content of8wt%,16wt%,24wt%and32wt%were prepared by solid-state synthesis. The results showed that the composite display a higher oxidation degree, doping degree and conductivity thanPANI. Galvanostatic charge–discharge measurements indicated that the compositewith8wt%SWNTs had relativly high specific capacitance, and its correspondingcapacitance retention ratio still reach to94%and80%in1M H2SO4and1M KClwith the growth of current densities from3to20mAcm-2.3． PANI/Anatase-TiO₂composites with the Anatase-TiO₂content of6.2wt%,12.8wt%,17.6wt%and24.1%were prepared by solid-state synthesis. The resultsshowed that the composite display a higher oxidation and doping degree thanPANI. And the composites showed a granular-like morphology of about200nm.Galvanostatic charge–discharge tests indicated that the composite with6.2wt%Anatase-TiO₂had the highest specific capacitance of523Fg-1, and displayed anideal capacitive behavior.4．PANI/Rutile-TiO₂composites with the Rutile-TiO₂content of0wt%,6.2wt%,12.8wt%,17.6wt%and24.1%were prepared by solid-state synthesis. The resultsshowed that the composite display a higher oxidation degree and thermal stabilitythan PANI. TEM indicated that the composites are not a simple mixture ofRutile-TiO₂and PANI. XRD revealed that the Rutile-TiO₂hampered thecrystallinity of composites. The electrochemical performances showed that thecapacitance can improve with appropriate content of Rutile-TiO₂in the composite.