Outstanding Room‐Temperature Thermoelectric Performance of n‐type Mg3Bi2‐Based Compounds Through Synergistically Combined Band Engineering Approaches

• DOI: 10.1002/adfm.202407017
• Publication Date: 2024-08-01T10:31:27Z
• Authors: Hyunyong Cho; Song Yi Back; Naoki Sato; Zihang Liu; Weihong Gao; Longquan Wang; Hieu Duy Nguyen; Naoyuki Kawamoto; Takao Mori
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract Thermoelectric cooling materials based on Bi 2 Te 3 have a long history of unsurpassed performance near room temperature. Recently, research into price‐competitive Mg (Bi, Sb) ‐based are focused replacing traditional materials. Here, the thermoelectric properties 3.2 1.998−x Sb x 0.002 Cu 0.005 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) polycrystalline compounds investigated. In all temperature regions, electrical resistivity Seebeck coefficient increased with concentration. The electronic transport Sb‐alloyed maximized by synergistically combined band engineering approaches such as structure change caused lattice strain, density states, chemical potential shift, leading to exceptionally high‐power factor values over 3.0 mW m −1 K −2 at Furthermore, increasing content, thermal conductivity systematically reduced due promotion alloy scattering phonons suppression bipolar contribution. Consequently, these multiple significantly enhance performance, resulting in an enhancement figure‐of‐merit zT above 1.1 348–423 K. Additionally, avg is recorded 300–450 K, making it unrivaled value among reported n‐type Overall, this work demonstrates that more promising for applications compared