Effects of the Interface between Inorganic and Organic Components in a Bi₂Te₃-Polypyrrole Bulk Composite on Its...

We provided a method to hybridize Bi₂Te₃ with polypyrrole, thus forming an inorganic/organic bulk composite (Bi₂Te₃-polypyrrole), in which the effects of energy band junction and phonon scattering were expected to occur at the interface of the two components. Bi₂Te₃-polypyrrole exhibited a considerably high Seebeck coefficient compared to pristine Bi₂Te₃, and thus it recorded a somewhat increased power factor despite the loss in electrical conductivity caused by the organic component, polypyrrole. Bi₂Te₃-polypyrrole also exhibited much lower thermal conductivity than pristine Bi₂Te₃ because of the phonon scattering effect at the interface. We successfully brought about the decoupling phenomenon of electrical and thermal properties by devising an inorganic/organic composite and adjusting its fabrication condition, thereby optimizing its thermoelectric performance, which is considered the predominant property for n-type binary Bi₂Te₃ reported so far.