Perspectives on thermoelectrics: from fundamentals to device applications

Abstract

aThis review is an update of a previous review 1 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, 5 strategies to improve 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 10 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, an efficiency measurements platform, and identifying applications are becoming increasingly important for the future of thermoelectrics.15

First-principles study of thermal transport inFeSb2

“…The scattering rates of acoustic modes and optical modes are plotted separately. A quadratic dependence of the normal scattering rates of acoustic phonons on frequency can be seen from the plot while the scattering rates of acoustic phonons for Umklapp processes seem to scale as ω 3 , a fact that is quite similar to silicon [32]. It is noticed that at T = 20 K, the phonon scattering rates are in general pretty low, and the phonon mean free paths can be comparable to the sample size, [32].…”

“…Thermoelectric materials are useful not only for generating electric power from heat, but also for providing cooling power by passing through an electric current [1][2][3][4][5][6][7][8][9]. They are especially attractive as refrigerators for being reliable, noiseless, and without any moving parts [4].…”

“…In this paper, we apply a first-principles formalism for the thermal conductivity calculation based on DFT and real-space lattice dynamics, recently developed [31,32] and verified for several realistic materials [33][34][35][36][37][38], to FeSb 2 to understand its intrinsic phonon-phonon interactions and, more importantly, provide the information of the phonon mean free path distribution, which is important in guiding the nanostructuring strategy for effectively reducing its thermal conductivity [3,9,11,39]. The detailed calculation procedures can be found in the references [31,32] and will only be briefly outlined here.…”

Changing of the Structure of the Contact Region of Thermoelectric Materials on the Basis of Bismuth Telluride at Elevated Temperatures

“…В стандартном термоэлек-трическом модуле термоэлементы помещены между двумя плоскими «керамическими пластинами» на основе оксида алюминия (рис. 1) [1].…”

Modeling and Experimentation of New Thermoelectric Cooler–Thermoelectric Generator Module

“…The efficiency of thermoelectric generators η and the coefficient of performance of thermoelectric coolers COP are the major challenges of the thermoelectric modules, which is why some research [15][16][17] has been carried out to expand the thermoelectric materials figure of merit (ZT) by maximizing Seebeck coefficient S [18,19] and the electric conductivity σ, minimizing the thermal conductivity k [20,21] of thermoelectric materials, and diminishing the manufacturing cost of the TEM [22,23]. However, remarkable progress has been made in the last decades in thermoelectric field since the first encounter of Seebeck effect; therefore, we can divide thermoelectric materials based on the figure of merit value into three generations [8].…”