Tuning PEDOT:Tos thermoelectric properties through nanoparticle inclusion

Thermoelectric application of conjugated polymers has recently become a subject of scientific interest. This is due to the peculiar features of these organic materials, such as low cost, safety, abundance of atomic components, and easy processing, which make them an interesting alternative to inorganic materials commonly used for this application in the room temperature range, i.e., tellurides derivatives, such as Bi2Te3 and Sb2Te3. Two are the main drawbacks of organic materials employment: the first is their poor thermoelectrical performance, which is still low in comparison with inorganic benchmark, the second is the scarcity of stable and easy-to-dope n-type polymers. In order to address the first issue, we tried to obtain a further and crucial efficiency improvement, developing a nanocomposite embedding inorganic nanoparticles in a matrix of conjugated polymer. A hybrid film of poly(3,4-ethylenedioxithiophene):Tosylate (PEDOT:Tos) and Mn3O4 nanoparticles have been achieved through a novel strategy, involving nanoparticle functionalization and in situ polymerization. The purpose is to enable energy filtering thanks to the presence of the NPs so as to extend this beneficial effect already been observed in inorganic semiconductor to polymers. Our study indicates a new path to obtain PEDOT-based nanocomposite and enlightens the peculiar behaviour of this hybrid material.