Rare Earth Makes the Best Better
One of the best materials for converting heat to electricity just got 15% better. Adding a small amount of dysprosium to the thermoelectric known as TAGS-85 raises the thermoelectric figure of merit from 1.3 to 1.5. Researchers examined the mechanism by which doping with dysprosium affects the thermopower. The size of dysprosium along with its local magnetic characteristics modifies the interplay between electronic and thermal transport. Dysprosium distorts the local crystalline lattice and enables higher energy carriers to move preferentially through the material. This leads to improved heat conversion. Understanding how doping impacts thermoelectric properties will help researchers design even better thermoelectric materials. An improvement of 0.2 in the figure of merit is a big step toward the goal of 2.0, which is regarded as the requirement for the commercialization of thermoelectric power generation.
- E. M. Levin, S. L. Bud’ko, and K. Schmidt-Rohr Enhancement of Thermopower of TAGS-85 High-Performance Thermoelectric Material by Doping with Rare Earth Dy. Advanced Functional Materials, 2012, 22, 2766-2774. DOI: 10.1002/adfm.201103049