Enhancement in thermoelectric performance of bismuth telluride based alloys by multi-scale microstructural effects
Abstract
Decoupling of interdependent thermoelectric parameters was considered as a crucial strategy to enhance the thermoelectric performance of bulk materials. Here multi-scale microstructural effects have been introduced by a simple hot deformation process to obtain high-performance n-type bismuth telluride based alloys. Highly preferred orientation enables a significant improvement in in-plane electrical conductivity. The donor-like effect (an interaction of antisite defects and vacancies), which can be adjusted by varying hot deformation temperature, was also considered responsible for the remarkable enhancement in power factor. Besides, the in-plane lattice thermal conductivity was greatly reduced by in situ