Double charge polarity switching in Sb-doped SnSe for enhanced thermo-electric power generation

The pristine and antimony (Sb) doped tin selenide (SnSe) has been prepared by vacuum melting followed by ball milling process. The crystallographic pattern of both doped and undoped samples shows the formation of orthorhombic SnSe without any impurities. The influence of Sb on SnSe were confirmed from Projected Density of States (PDOS) and electron density analysis. The Elemental Probe Micro Analyzer (EPMA) technic used to confirm the presence of Sn, Se and Sb elements along with homogenous distribution. HR-TEM micrographs reveal highly crystalline nature of the samples as well as the formation of defects and distinguishable grains and grain boundaries, which helps to reduce the thermal conductivity of 10 wt% Sb doped SnSe samples to 0.55 W/mK at 600 K. Seebeck coefficient analysis has been discloses the double charge polarity switching in Sb substituted samples. Thus, 10 wt% Sb doped SnSe samples achieved a comparable negative Seebeck coefficient with respect to pristine SnSe, which can be a breakthrough in thermoelectric devices. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The pristine and antimony doped tin selenide (SnSe) samples were prepared by vacuum melting followed by ball milling process. The crystallographic patterns confirmed the formation of orthorhombic SnSe without impurities. The influence of antimony on SnSe was confirmed through Projected Density of States (PDOS) and electron density analysis. Elemental Probe Micro Analyzer (EPMA) technique confirmed the presence and homogeneous distribution of Sn, Se, and Sb elements. HR-TEM micrographs revealed highly crystalline nature of the samples as well as the formation of defects and distinguishable grains and grain boundaries. The thermal conductivity of 10 wt% Sb doped SnSe samples was reduced to 0.55 W/mK at 600 K. Seebeck coefficient analysis disclosed the double charge polarity switching in Sb substituted samples. Thus, the 10 wt% Sb doped SnSe samples achieved a comparable negative Seebeck coefficient with respect to pristine SnSe, which can be a breakthrough in thermoelectric devices.