Robust Homogeneous Segmented Power Generator Driven by Sb<sub>2</sub>Te<sub>3</sub>‐Based Thermoelectrics
Min Wang, Xue‐Qiang Zhang, Kaikai Pang, Minhui Yuan, Qiaoyan Pan, Ruyuan Li, Liya Miao, Xiaojian Tan, Haoyang Hu, Jiehua Wu, Peng Sun, Guoqiang Liu, Jun Jiang
Abstract
Abstract Thermoelectric (TE) technology offers a promising solution for waste heat recovery, particularly in applications involving abundant low‐grade heat (<650 K). However, for over half a century, TE power generators have predominantly relied on Bi 2 Te 3 alloys with limited efficiencies below 7%. Herein, Cd and S are doped into Sb 2 Te 3 to promote microstructural regulation characterized by dense twin boundaries and dislocations, resulting in a 45% reduction of lattice thermal conductivity at 300 K. Combined with the optimized density‐of‐states effective mass and expanded band gap, the Cd 0.04 Sb 1.96 Te 2.94 S 0.06 sample attains a peak ZT of 1.1 at 650 K and an average ZT of 1.0 from 500 to 650 K, while exhibiting remarkable compressive and bending strengths of 197 and 56 MPa. Most importantly, a well‐designed, homogeneous segmented TE power generator, constructed entirely from Bi–Sb–Te alloys, achieves a remarkable efficiency of 9.3% under a temperature gradient of 350 K, as certified by third‐party validation. This work provides new insights into extending the operation temperature of Bi 2 Te 3 , demonstrating great potential for low‐grade waste heat harvest.