Abstract
Understanding the formation of various point defects in the promising thermoelectric material, β-Zn(4)Sb(3), is crucial for theoretical determination of the origins of its p-type behavior and considerations of potential n-type dopability. While n-type conductivity has been fleetingly observed in Te:ZnSb, there have been no reports, to the best of our knowledge, of stable n-type behavior in β-Zn(4)Sb(3). To understand the origin of this difficulty, we investigated the formation of intrinsic point defects in β-Zn(4)Sb(3) density functional theory calculations. We found that a negatively charged zinc vacancy is the dominant defect in β-Zn(4)Sb(3), as it is also in ZnSb. This explains the unintentional p-type behavior of the material and makes n-doping very difficult since the formation of the defect becomes more favorable at higher Fermi levels, near the conduction band minimum (CBM). We also calculated the formation energy of the cation dopants: Li, Na, B, Al, Ga, In, Tl; of these, only Li and Na are thermodynamically favorable compared to the acceptor Zn vacancy over a range of Fermi levels along the band gap. Further analysis of the band structure shows that Li:Zn(4)Sb(3) has a partially occupied topmost valence band, making th...Continue Reading
References
Dec 15, 1994·Physical Review. B, Condensed Matter·P E Blöchl
Feb 15, 1995·Physical Review. B, Condensed Matter·G Makov, M C Payne
Oct 15, 1996·Physical Review. B, Condensed Matter·G Kresse, J Furthmüller
Jan 1, 1993·Physical Review. B, Condensed Matter·G Kresse, J Hafner
May 15, 1994·Physical Review. B, Condensed Matter·G Kresse, J Hafner
Oct 28, 1996·Physical Review Letters·J P PerdewM Ernzerhof
Sep 16, 2000·Physical Review Letters· Van De Walle CG
May 31, 2002·Acta Crystallographica. Section B, Structural Science·Alec BelskyPeter Luksch
Jun 29, 2004·Nature Materials·G Jeffrey SnyderBo Brummerstedt Iversen
Aug 19, 2004·Chemistry : a European Journal·Fausto CargnoniBo Brummerstadt Iversen
Jun 9, 2005·Chemistry : a European Journal·Arkady S MikhaylushkinUlrich Häussermann
Sep 14, 2006·Journal of the American Chemical Society·Georg K H Madsen
Jan 26, 2008·Nature Materials·G Jeffrey Snyder, Eric S Toberer
Jun 21, 2011·International Journal of Molecular Sciences·Jian-Hua ZhaoWen Zeng
Mar 6, 2012·Advanced Materials·Ye SunBo B Iversen
Jun 15, 2013·Chemical Communications : Chem Comm·Hao YinBo Brummerstedt Iversen
Dec 25, 2013·Journal of the American Chemical Society·Jianping LinJu Li
Jun 7, 2014·ACS Applied Materials & Interfaces·Hao YinBo Brummerstedt Iversen
Citations
Aug 2, 2016·Physical Chemistry Chemical Physics : PCCP·Alireza FaghaniniaCynthia S Lo
Oct 11, 2016·Dalton Transactions : an International Journal of Inorganic Chemistry·Mette Andersen BorupBo Brummerstedt Iversen
Jul 20, 2017·The Journal of Physical Chemistry Letters·Alex PolizzottiTonio Buonassisi
Oct 11, 2017·Chemphyschem : a European Journal of Chemical Physics and Physical Chemistry·Duc-The NgoNgo Van Nong