Characterization of Polyaniline/Graphene Nanocomposites by Electrochemical, Spectroscopic, Thermal and Conductivity Analysis
Aleksandar Petrovski1, Anita Grozdanov1, Perica Paunovic1, Roberto Avolio2, Maria E.Errico2,Beti Andonovic1,Maria Cristina Coca2, Gennaro Gentile2, Francesca De Falco2, Maurizio Avella2 and Aleksandar Dimitrov1
1- Faculty of Technology and Metallurgy, University Ss Cyril and Methodius in Skopje, Republic of Macedonia
2- Institute for Polymers, Composites and Biomaterials- IPCB-CNR, Fabricato Oliveti, Via Campi Flegrei 78, Pozzuoli (NA) Italy
Among the conducting polymers, Polyaniline (PANI) is one of the most intrigued materials owing to its easy method of preparation, high electrical conductivity and high stability in environmental conditions. On the other hand, Graphene nanosheets exhibits unique properties such as very high electrical conductivity due to their very high electron mobility. Bringing together the propertis of these two matherials, sinergetic efect can be reached and their nanocomposites becomes very promising matherials in potential applications such as sensors, catalysis, capacitors, displays and many other devices.
In this investigation, nanocomposites were prepared by using electrochemical synthesis of conductive polymer matrix (PANI) and modified Graphene with functional groups - COOH. Here were synthesized two types of nanocomposites: first with graphene deposited on the Pt-electrode and then electropolymerisation of the PANI, and second with graphene dispersed in the electrolyte and mutual deposition on the Pt-electrode. Characterization was performed by several techniques: cyclic voltammetry, potentiostatic voltametry, FTIR, UV-VIS, TGA/DTA, Raman, SEM, and electrical measurements by surface resistivity.
Compared to neat PANI, CV curves in the presence of Graphene have shown remarkable higher anodic and cathode peaks. Analysing the intensities and the shiftings of the peaks in FTIR, UV-VIS, and Raman spectars, Graphene is very well introducted in PANI matrix. The morphological study of the modified Graphene based nanocomposites showed porous fibrilar morphology, and confirms the previous conclusion. The obtained composites exhibited bether thermal stability compared to neat PANI and a higher value of conductivity which may be attributed to the synergy effect of the conductive polymer matrix and graphene nanostructure. These nanocomposites are promising matherials for further investigations in the field of sensors, capacitors, bateries and many other electronic devices.
Key words: Polyaniline, graphene, nanocomposites, electrochemical synthesis, properties