Enhanced thermoelectric properties of SnSe polycrystals via texture control

Dan Feng; Zhen-Hua Ge; Di Wu; Yue-Xing Chen; Tingting Wu; Ju Li; Jiaqing He

doi:10.1039/c6cp06466c

Enhanced thermoelectric properties of SnSe polycrystals via texture control

Phys Chem Chem Phys. 2016 Nov 23;18(46):31821-31827. doi: 10.1039/c6cp06466c.

Authors

Dan Feng¹, Zhen-Hua Ge², Di Wu³, Yue-Xing Chen³, Tingting Wu³, Ju Li⁴, Jiaqing He³

Affiliations

¹ State Key Laboratory for Mechanical Behavior of Materials and Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China. liju@mit.edu and Shenzhen Key Laboratory of Thermoelectric Materials, Department of physics, South University of Science and Technology of China, Shenzhen 518055, China. he.jq@sustc.edu.cn.
² Shenzhen Key Laboratory of Thermoelectric Materials, Department of physics, South University of Science and Technology of China, Shenzhen 518055, China. he.jq@sustc.edu.cn and Faculty of Materials Science and Technology, Kunming University of Science and Technology, Kunming, 650093, China.
³ Shenzhen Key Laboratory of Thermoelectric Materials, Department of physics, South University of Science and Technology of China, Shenzhen 518055, China. he.jq@sustc.edu.cn.
⁴ State Key Laboratory for Mechanical Behavior of Materials and Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China. liju@mit.edu and Department of Nuclear Science and Engineering and Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

PMID: 27841409
DOI: 10.1039/c6cp06466c

Abstract

We present in this manuscript that enhanced thermoelectric performance can be achieved in polycrystalline SnSe prepared by hydrothermal reaction and spark plasma sintering (SPS). X-ray diffraction (XRD) patterns revealed strong orientation along the [l 0 0] direction in bulk samples, which was further confirmed by microstructural observation through transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). It was noticed that the texturing degree of bulk samples could be controlled by sintering temperature during the SPS process. The best electrical transport properties were found in the sample which sintered at 450 °C in the direction vertical to the pressing direction, where the highest texturing degree and mass density were achieved. Coupled with the relatively low thermal conductivity, an average ZT of ∼ 0.38, the highest ever reported in pristine polycrystalline SnSe was obtained. This work set up a forceful example that a texture-control approach can be utilized to enhance the thermoelectric performance effectively.