Free-standing and flexible polypyrrole nanotube/reduced graphene oxide hybrid film with promising thermoelectric performance

Free-standing and flexible polypyrrole (PPy) nanotube/reduced graphene oxide (rGO) hybrid films were prepared by vacuum filtration of a mixture of PPy nanotubes and GO nanosheets followed by hydrogen iodide (HI) treatment. The hybrid films were fabricated by the homogeneous intercalation of PPy nanotubes into the lamellar rGO nanolayers. The unique network in the PPy nanotube/rGO hybrid films helped to prevent the aggregation of graphene nanosheets and supply effective conducting channels for electron transfer. As a result, the films exhibited improved flexibility, mechanical strength and electrical conductivity. The power factor of PPy/rGO hybrid film at room temperature was about 135 times larger than that of PPy nanotube film. Furthermore, the PPy/rGO hybrid films exhibited excellent stable thermoelectric performance after repeated mechanical bending. These results indicate that PPy nanotube/rGO hybrid film exhibits promising potential for application in high-performance and flexible thermoelectric materials.