Detail:
Abstract: There is huge effort in searching for high-performance thermoelectric (TE) materials in recent years. For that, understanding the thermal and electrical transports in complex materials is the key scientific issues to be pursued. This talk will try to summarize our efforts in understanding thermoelectric transports in compound materials with different level of structural complexity. The complexity gives rise to many opportunities for new findings. For examples, in the materials with chemical-bond hierarchy, in which certain constituent species weakly bond to other part of the crystal, an unusual part-crystalline part-liquid state (or liquid-like) of materials exists and leads to certain exotic thermal transport and phonon scattering beyond the traditional phonon anharmonicity. I will also shortly discuss the pseudocubic approach that could be adopted to realize good electronic transport properties in thousands non-cubic chalcopyrites through the utilization of cubic-like degenerate electronic bands, via the coexistence of a long-range cubic framework with short-range non-cubic lattice distortions. Some other efforts in tuning the electrical/thermal transports will also be briefly discussed.