Achieving metal-like malleability and ductility in Ag2Te1- x S x inorganic thermoelectric semiconductors with high mobility

Huiping Hu; Yuechu Wang; Chenguang Fu; Xinbing Zhao; Tiejun Zhu

doi:10.1016/j.xinn.2022.100341

Achieving metal-like malleability and ductility in Ag₂Te_{1- x} S _x inorganic thermoelectric semiconductors with high mobility

Innovation (Camb). 2022 Oct 18;3(6):100341. doi: 10.1016/j.xinn.2022.100341. eCollection 2022 Nov 8.

Authors

Huiping Hu¹, Yuechu Wang¹, Chenguang Fu¹, Xinbing Zhao¹, Tiejun Zhu¹

Affiliation

¹ State Key Laboratory of Silicon Materials, and School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.

Abstract

Inorganic semiconductor Ag₂Te_1-x S _x has been recently found to exhibit unexpected plastic deformation with compressive strain up to 30%. However, the origin of the abnormal plasticity and how to simultaneously achieve superb ductility and high mobility are still elusive. Here, we demonstrate that crystalline/amorphous Ag₂Te_1-x S _x (x = 0.3, 0.4, and 0.5) composites can exhibit excellent compressive strain up to 70% if the monoclinic Ag₂Te phase, which commonly exists in the matrix, is eliminated. Significantly, an ultra-high tensile elongation reaching 107.3% was found in Ag₂Te_0.7S_0.3, which is the highest one yet reported in the system and even surpasses those achieved in some metals and high-entropy alloys. Moreover, high mobility of above 1000 cm² V^-1 s^-1 at room temperature and good thermoelectric performance are simultaneously maintained. A modified Ashby plot with ductility factor versus carrier mobility is thereby proposed to highlight the potential of solid materials for applications in flexible/wearable electronics.

Keywords: carrier mobility; plastic deformability; silver chalcogenides; thermoelectric materials; thermoelectric performance.