High thermoelectric performance in GeTe with compositional insensitivity. (1st December 2022)

• Record Type: Journal Article
• Authors: Dong, Jinfeng; Jiang, Yilin; Liu, Jiawei; Pei, Jun; Tan, Xian Yi; Hu, Haihua; Suwardi, Ady; Jia, Ning; Liu, Chuntai; Zhu, Qiang; Yan, Qingyu; Li, Jing-Feng
• Is Part Of: Nano energy. Volume 103(2022)Part A
• Publication Date: 2022-12-01
• Subjects: Thermoelectric -- Germanium telluride -- Compositional insensitivity; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2022.107809
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Thermoelectric materials have obtained worldwide attention as they are attractive for waste heat recovery and solid-state cooling. However, their performance is usually sensitive to material compositions, which is less favorable for industrial applications. In this work, we developed composition-insensitive GeTe-based compounds ((100- x - y )%GeTe- x %CuBiSe2 - y %PbTe, CBS x -Pb y ) with high ZT max as well as ZT ave values. The compositional insensitivity can be associated with the persistently high quality factors across the range of compositions. This is largely due to the interplay between electrical and thermal transport caused by the synergy of CuBiSe2 and PbTe alloying. CuBiSe2 alloying can effectively tune the carrier concentrations, while PbTe alloying can significantly decrease the thermal conductivity at a minor sacrifice of electrical properties. The combined effects of CuBiSe2 and PbTe alloying lead to high carrier mobility of 60 cm 2 V −1 s −1 and low thermal conductivities for CBS x -Pb y samples simultaneously. Consequently, high ZT ave values of 1.4–1.5 in the temperature range of 400 K and 773 K for broad compositions (CBS3-Pb y, y = 2 – 8 and CBS x -Pb6, x = 2 – 5) are achieved. A single-leg module is also fabricated, which shows a high power density of 1.46 W/cm 2 and an excellent efficiency of 13.4%. The high ZT ave with compositional insensitivity and the outstanding module performance demonstrate the promising large-scale application of the developed GeTe-based compositions. Graphical Abstract: A GeTe-based material with composition-insensitive high performance has been developed, which presents outstanding maximum ZT values of ∼2.0 at 600–773 K and average ZT values of 1.4–1.5 in the temperature ranges of 400 K and 773 K. The fabricated prototype module also exhibits high power density of 1.46 W/cm 2 and an efficiency of 13.4%. ga1 Highlights: Composition-insensitive high thermoelectric properties are obtained in GeTe-based compound with ZT of ∼2.0 and ZT ave of 1.4–1.5. The achievement of high thermoelectric performance is due to the interplay between electrical and thermal transport. Single-leg module demonstrates the promising application with high power density of 1.46 W/cm 2 and efficiency of 13.4%