ICT2014 Abstracts

  Inorganic semiconductors have been primarily the materials of choice for thermoelectrics, but an interest in organic materials is growing recently. We report a hybrid organic/inorganic superlattice as a novel thermoelectric material, in which metallic TiS₂ monolayer and organic molecules stack alternatively, which has been confirmed by the TEM observation. It was found this organic/inorganic superlattice could almost maintain the high electron mobility of the inorganic component while significantly suppressing the thermal conductivity. We obtained a reasonably high ZT of 0.28 at 377K for TiS₂/hexylammonium with an extremely low lattice thermal conductivity of 0.12Wm^-1K^-1. The infinite substitutions of organic components could make this kind of inorganic/organic superlattices a promising class of thermoelectric materials due to its interesting physics. For example, we found the electron mobility of the hybrid material can be systematically increased by employing different organic molecules with increasing dielectric constant as a result of dielectric screening effect.