Year: 2019
Type: article
Abstract: PbTe-based compositions are considered as excellent thermoelectric materials for the mid-temperature.However, the toxicity of lead limits its wide application.SnTe compounds, an analogue of PbTe, has attracted much attention.However, its ultrahigh carrier concentration and the large lattice thermal conductivity leads to a low ZT value of SnTe.In this work, the thermoelectric performance of SnTe is synergistically enhanced by introduction of Sn and SnO 2 from the disproportionation of SnO in the process of the hot press sintering.On the one hand, Sn can compensate the Sn vacancies and decrease the carrier concentration of SnTe, leading to a simultaneous enhancement on resistivity and the Seebeck coefficient.For instance, compared with the pristine SnTe, resistivity and the Seebeck coefficient increases from 6.5 m to 10.5 m and from 105 VK -1 to 146 VK -1 , respectively, for the sample of SnTe-6mol% SnO at 873 K. On the other hand, in-situ generated SnO 2 nanoparticles are dispersedly distributed on the grain boundaries, leading to the multiscale phonon scattering and the reduced lattice thermal conductivity.The minimum lattice thermal conductivity value is 0.6 Wm -1 K -1 for the sample SnTe-6mol% SnO at 873 K, which is ~33% reduction compared with that of the pristine SnTe.As a result, the maximum ZT value of 0.96 (~100% enhancement,
Source: Journal of Inorganic Materials
DOI: 10.15541/jim20180288
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W2921586049