Polyaniline-based composites as thermoelectric materials

Thermoelectric (TE) materials can convert heat into electricity when a temperature gradient is present. The investigation of conductive polymers such as polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT) as active materials for thermoelectric generators in the room temperature range is gaining interest because of several key advantages offered by these materials. The relative easiness of solution processing, their mechanical stability and flexibility together with low density and low thermal conductivity make conductive polymers suitable for integration in a thermoelectric generator. Polymers offer remarkably low thermal conductivity values but modest Seebeck coefficient and electrical conductivity. Polymer/inorganic composites of PANI were produced by adding high-conductive single wall carbon nanohorns (SWCNHs) or thermoelectric metal chalcogenides nanoparticles belonging to the tetrahedrite family Cu12Sb4S13 as fillers to improve the thermoelectric performance by means of polymer matrix/inorganic particle electronic junction. Electrical conductivity, Seebeck coefficient and thermal conductivity were estimated on PANI-based composite films and pressed pellets. The thermal stability was evaluated by means of thermogravimetric analysis/differential scanning calorimetry coupled with residual gas analysis .