High Thermoelectric Figure of Merit and Nanostructuring in Bulk p‐type Na_1−xPb_mSb_yTe_m+2

Abstract

Thermoelectric materials are special types of semiconductors that function as "heat pumps" and as heat-to-electricity converters. Thermoelectric power generation allows for small size, high reliability, and quiet operation. Efficient thermoelectric-based heat-to-electricity converters require higher performance materials than are currently available.[1, 2] Direct conversion of heat to electricity could be achieved with solidstate devices based on thermoelectric materials. These devices could play an important role in future energy production, conversion, management, and utilization. When a temperature gradient is created across a thermoelectric

Comprehensive Review of Heat Transfer in Thermoelectric Materials and Devices

“…NaPb m SbTe 2+m (SALT-m) is also a highperformance p-type material (ZT~1.7 at 650 K). The impressive ZT is also attributed to the very low lattice thermal conductivity (0.74 W/mK at 300 K and 0.55 W/mK at 650 K) caused by pervasive nanostructuring 108 .…”

Weak electron–phonon coupling contributing to high thermoelectric performance in n-type PbSe

“…The search for good thermoelectric materials has focused on investigating semiconductors that have suitable band structures and low thermal conductivities (3,4). As one of the first investigated material systems (5), PbTe and its alloys have been extensively studied and remain some of the best (6, 7) thermoelectric materials for applications from 500 to 900 K. Considerable effort has been made to achieve a higher zT in these alloys by reducing the lattice thermal conductivity, κ L , by incorporation of nanometer scale inclusions (8)(9)(10)(11). Other strategies approach the challenge of increasing zT from different angles, such as band structure distortion by Tl doping (12), and more recently, increasing band degeneracy by converging two different valence bands in p-type PbTe (13).…”

Contrasting role of antimony and bismuth dopants on the thermoelectric performance of lead selenide

“…Thus, increasing such conversion efficiency requires both high ZT and a large temperature gradient across the materials. One effective way to achieve high ZT is to reduce lattice thermal conductivity through embedding micro/nanostructures, which provide multiple scattering mechanisms for phonons 1,2,[4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . Other strategies address the challenge of maximizing a power factor from existing semiconducting materials by band alignment 5,6,19,20 , modifying their electronic structures close to the Fermi level 21,22 , and increasing band degeneracy by convergence of bands 23 .…”