Naslov
Low-temperature electronic properties of single crystal SnSe thermoelectric

Autori
Popčević, Petar ; Gille, P.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Solid-State Science & Research, Book of Abstracts / Juribašić Kulcsar, Marina ; Halaz, Ivan - Zagreb : Institut Ruđer Bošković, 2017, 60-60

ISBN
978 953 7941-15-4

Skup
Solid-State Science & Research

Mjesto i datum
Zagreb, Hrvatska, 2017

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
electronic properties, single crystal SnSe, thermoelectrics

Sažetak
Intermetallic compound SnSe has long been known [1, 2], but its enormous thermoelectric potential was revealed just recently [3]. In this layered system, thermoelectric figure of merit ZT reaches its peak value of 2.62 at 923 K. This high ZT value is realized only in high-temperature phase that exists above 750- 800 K while at room temperature, SnSe has considerably smaller ZT value. Several groups [4-6] have suggested that application of hydrostatic or uniaxial pressure could lower transition temperature and thus enhance ZT value in low-temperature region. In line with those theoretical predictions, recent x-ray study [6] revealed structural phase transition at 10.5 GPa to a phase that is closely related to the high-temperature one. In an attempt to monitor this phase transition through transport properties, we investigated low-temperature phase at ambient pressure. System behaves like heavily doped semiconductor, most likely due to some Se vacancies. At room temperature, Fermi level approaches valence band and electrical resistivity shows metallic behavior. Close to 70 K, metal to insulator (MIT) transition is observed while below 10 K hopping of localized charge carriers is the most effective mechanism in electrical conductivity. Seebeck coefficient shows metallic behavior in the whole temperature range with rather sharp change of slope at MIT transition. Magneto-transport shows negative contribution at low temperatures consistent with Zeeman splitting of localized states in hoping regime. [1] J. G. Yu, et al., J. Cryst. Growth 54 (1981) 248. [2] J. D. Wasscher, et al., Solid-State Electron. 6 (1963) 261. [3] L.-D. Zhao, et al., Nature 508 (2014) 373. [4] S. Alptekin, J. Mol. Model. 17 (2011) 2989. [5] S.M. de Suoza, et al., J. Appl. Cryst. 49 (2016) 213. [6] I. Loa, et al., J. Phys. Condens. Matter 27 (2015) 072202.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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