Photothermoelectric Effect of Graphene-polyaniline Composites

Graphene and polyaniline with thermoelectric properties are one of the potential substitutes for inorganic materials for flexible thermoelectric applications. In this study, we studied the photo-induced thermoelectric effect of graphene-polyaniline composites. The graphene-polyaniline composites were synthesized by introducing an amine functional group to graphene oxide for covalently connecting graphene and polyaniline, reducing the graphene oxide, and then polymerizing the graphene oxide with aniline. Graphene-polyaniline composites were prepared by changing the aniline contents in order to expect an optimal photothermoelectric effect, and their structural properties were confirmed through FT-IR and Raman analysis. The photocurrent and photovoltage characteristics were analyzed by irradiating light asymmetrically without an external bias and the current and voltage with various aniline contents. While the photocurrent trends to the electrical conductivity of the graphene-polyaniline composites, the photovoltage was related to the temperature change of the graphene-polyaniline composite, which was converted into thermal energy by light.