Investigation of an amphoteric behaviour of arsenic dopant in polycrystalline SnSe
ČlánekOtevřený přístuppeer-reviewedpublishedDatum publikování
2018
Vedoucí práce
Oponent
Název časopisu
Název svazku
Vydavatel
University of Pardubice
Abstrakt
We investigated eventual amphoteric behaviour of As atoms in SnSe by substituting in either cation or anion site. The investigation involved two series of polycrystalline samples of nominal composition Sn1-xAsxSe (0 ≤ x ≤ 0.1) and SnAsxSe1-x (0 ≤ x ≤ 0.08). The prepared powders were identified by X-ray diffraction. Hot-pressed from powder, polycrystalline pellets were used for characterization of transport and thermoelectric properties in temperature range of 300–730 K. An embedding of the As atoms in either cation or anion site seems to prevent formation of the major defects present in the undoped SnSe, tin vacancies VSn2-. Instead, selenium vacancies VSe2+ together with substitutional defects AsSn+ play the major role in the electronic transport in the Sn1-xAsxSe system. Due to rather low solubility of arsenic in the system (x ≤ 0.02), either As inclusions or amorphous As-Se phase is formed in highly doped samples. In the case of SnAsxSe1-x, As atoms enter Se position forming AsSe-, which increases the hole concentration in the doped samples at lower temperatures. At higher temperatures, the properties of the compounds (for x ≤ 0.03) are influenced by the formation of highly conductive AsSn phase. Generally, the substitution of As for both anion and cation lead to no evident enhancement of the thermoelectric figure of merit ZT.
Rozsah stran
p. 87 - 100
ISSN
1211-5541
Trvalý odkaz na tento záznam
Projekt
Zdrojový dokument
Scientific papers of the University of Pardubice. Series A, Faculty of Chemical Technology. 24/2018
Vydavatelská verze
Přístup k e-verzi
open access
Název akce
ISBN
978-80-7560-167-4
Studijní obor
Studijní program
Signatura tištěné verze
Umístění tištěné verze
Přístup k tištěné verzi
Klíčová slova
tin selenide, arsenic, doping, thermoelectric properties