Thermoelectric performances of graphene/polyaniline composites prepared by one-step electrosynthesis

Composite films comprising graphene and polyaniline were prepared in one step by a facile electrochemical technique with graphene oxide (GO) and aniline monomer as raw materials, and their thermoelectric properties were investigated. Electrical conductivities of the composite films generated on the fluorine-doped tin oxide (FTO) electrode were dependent on the weight ratio of GO and aniline, and they exhibited a peak value of 30 S cm −1 at the GO/aniline ratio between 5 : 1 and 10 : 1, while Seebeck coefficients were less dependent on the weight ratio. The maximum power factor ( PF ) for the composite films was ca. 1 μW m −1 K −2 . When the FTO electrode was replaced by the stainless steel electrode, conductivities of the composite films with the GO/aniline ratio of 8 : 1 were increased up to ca. 130 S cm −1 . As a result, the PF and the dimensionless thermoelectric figure-of-merit ( ZT ) at room temperature reached 3.6 μW m −1 K −2 and 0.008, respectively. The ZT value is the highest among those reported so far for graphene/PANI composites. Possible reasons for the conductivity enhancement on the stainless steel electrode are also discussed on the basis of electrochemical measurements and X-ray photoelectron spectroscopy. Graphene/polyaniline composites prepared by one-step electrosynthesis of graphene oxide and aniline monomer give a dimensionless thermoelectric figure-of-merit (ZT) of 0.009.