@article{Wang2025, 
author = {Liangsheng Wang and Shunjian Xu and Jian Yang and Xinyu Tang and Xinyu Wang and Guanjun Qiao and Guiwu Liu},
title = {Achieving ultrahigh power factor in Mg3(Sb,Bi)2-based thermoelectric alloys sintered by introducing elemental Mg and W},
year = {2025},
journal = {Journal of Advanced Ceramics},
volume = {14},
number = {2},
pages = {9221029},
keywords = {liquid phase sintering, thermoelectric performance, Mg3(Sb,Bi)2, grain boundary scattering},
url = {https://www.sciopen.com/article/10.26599/JAC.2025.9221029},
doi = {10.26599/JAC.2025.9221029},
abstract = {Improving the power factor (PF) of thermoelectric materials is crucial for increasing the output power density and broadening practical applications. The near-room-temperature electrical performance of Mg3(Sb,Bi)2-based alloys is hindered due to the presence of Mg vacancies and grain boundary scattering, resulting in a lower power factor. In this study, we introduced excess Mg into Mg3(Sb,Bi)2 alloy during the hot-pressing process, triggering a liquid phase sintering process, which can effectively fill the Mg vacancies and increase the average grain size (Dave) to significantly reduce grain boundary scattering. This leads to enhanced room-temperature electrical conductivity (σ) without detrimental effects on the Seebeck coefficient (S), thus yielding a high average PF of ~25.3 μW·cm−1·K−2 and an average figure of merit (ZT) of ~1.03 within the temperature range of 323‒623 K. Moreover, different amounts of W were further added, and density-functional theory (DFT) calculations reveal that W segregation at grain boundaries (GBs) reduces interfacial potential barriers, leading to improved S and σ. Consequently, an ultrahigh average PF of ~26.2 μW·cm−1·K−2 was attained in the W0.06Mg3.2Sb1.5Bi0.49Te0.01–4% Mg alloys. Additionally, the mechanical properties (Vickers hardness and fracture toughness) were also enhanced compared with those of the pristine Mg3(Sb,Bi)2 alloy. This dual-modified approach can significantly boost the TE performance and mechanical stability, advancing Mg3(Sb,Bi)2-based materials for practical applications.}
}