Low-Temperature, Solution-Based, Scalable Synthesis of Sb2Te3 Nanoparticles with an Enhanced Power Factor

• Published in: Journal of electronic materials 2014-06, Vol.43 (6), p.2165-2173
• Main Authors: Yang, Heng Quan, Miao, Lei, Zhang, Ming, Ohno, Kaoru, Zhou, Jian Hua, Gu, Hui, Shen, Yang, Lin, Hong
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; Cross-disciplinary physics: materials science; rheology; Electronic transport in condensed matter; Electronics and Microelectronics; Exact sciences and technology; Instrumentation; Materials Science; Methods of crystal growth; physics of crystal growth; Nanoscale materials and structures: fabrication and characterization; Optical and Electronic Materials; Other topics in nanoscale materials and structures; Physics; Solid State Physics; Theory and models of crystal growth; physics of crystal growth, crystal morphology and orientation; Thermoelectric and thermomagnetic effects
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-014-2995-7

Nanostructured thermoelectric (TE) materials, for example Sb 2 Te 3 , PbTe, and SiGe-based semiconductors, have excellent thermoelectric transport properties and are promising candidates for next-generation TE commercial application. However, it is a challenge to synthesize the corresponding pure nanocrystals with controlled size by low-temperature wet-chemical reaction. Herein, we report an alternative versatile solution-based method for synthesis of plate-like Sb 2 Te 3 nanoparticles in a flask using SbCl 3 and Te powders as raw materials, EDTA-Na 2 as complexing agent, and NaBH 4 as reducing agent in the solvent (distilled water). To investigate their thermoelectric transport properties, the obtained powders were cold compacted into cuboid prisms then annealed under a protective N 2 atmosphere. The results showed that both the electrical conductivity ( σ ) and the power factor ( S 2 σ ) can be enhanced by improving the purity of the products and by increasing the annealing temperature. The highest power factor was 2.04  μ W cm −1  K −2 at 140°C and electrical conductivity remained in the range 5–10 × 10 3  S m −1 . This work provides a simple and economic approach to preparation of large quantities of nanostructured Sb 2 Te 3 with excellent TE performance, making it a fascinating candidate for commercialization of cooling devices.