Perspectives on thermoelectrics: from fundamentals to device applications

TLDR

This review updates recent progress in thermoelectric materials, highlighting advances in phonon and electron transport, high‑ZT achievements, and emerging challenges in device physics. The paper aims to develop device contacts, module fabrication techniques, an efficiency‑measurement platform, and identify applications to advance thermoelectrics. The authors review recent strategies to enhance electron transport and overall thermoelectric performance, discuss device physics, and outline challenges for future development.

Abstract

This review is an update of a previous review (A. J. Minnich, et al., Energy Environ. Sci., 2009, 2, 466) published two years ago by some of the co-authors, focusing on progress made in thermoelectrics over the past two years on charge and heat carrier transport, strategies to improve the thermoelectric figure of merit, with new discussions on device physics and applications, and assessing challenges on these topics. Understanding of phonon transport in bulk materials has advanced significantly as the first-principles calculations are applied to thermoelectric materials, and experimental tools are being developed. Some new strategies have been developed to improve electron transport in thermoelectric materials. Fundamental questions on phonon and electron transport across interfaces and in thermoelectric materials remain. With thermoelectric materials reaching high ZT values well above one, the field is ready to take a step forward and go beyond the materials' figure of merit. Developing device contacts and module fabrication techniques, developing a platform for efficiency measurements, and identifying applications are becoming increasingly important for the future of thermoelectrics.