(1. State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China) (2. Department of Physics, Southern University of Science and Technology, Shenzhen 518000, China)
Thermoelectric materials that realize the direct energy conversion between heat and electricity, have been considered as promising alternatives to meet the challenges of the global energy dilemma. However, the low energy conversion efficiency limits its wide application. The properties of thermoelectric materials are closely related to its microstructure(such as point defects, dislocations, interfaces, second phase particles, pores, etc.), the precise microstructure characterization of thermoelectric materials not only is crucial to profoundly understanding the material itself, but also helps to design new materials with properties. In this review, we illustrate the structure-property correlations from the perspective of calculation formula of electrical and thermal transport performance, and show how to tune the electrical and thermal transport performance of thermoelectric materials through structure control.The application of transmission electron microscope in thermoelectric materials is reviewed, including the characterization of atomic, nano and mesoscopic full-scale defect structures.