Selecting the suitable dopants: electronic structures of transition metal and rare earth doped thermoelectric sodium cobaltate

Engineered Na sub(0.75)CoO sub(2) is considered a prime candidate to achieve high efficiency thermoelectric systems to regenerate electricity from waste heat. In this work, three elements with outmost electronic configurations, (1) an open dshell (Ni), (2) a closed dshell (Zn), and (3) a half filled...

Full description

Saved in:
Bibliographic Details
Published in:RSC advances 2013-01, Vol.3 (5), p.1442-1449
Main Authors: Assadi, M. H. N., Li, S., Yu, A. B.
Format: Article
Language:English
Subjects:
Dopants
Electronics
Energy of formation
Fermi surfaces
Nickel
Rare earth metals
Sodium
Thermoelectricity
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Engineered Na sub(0.75)CoO sub(2) is considered a prime candidate to achieve high efficiency thermoelectric systems to regenerate electricity from waste heat. In this work, three elements with outmost electronic configurations, (1) an open dshell (Ni), (2) a closed dshell (Zn), and (3) a half filled fshell (Eu) with maximum unpaired electrons, were selected to outline the dopants' effects on the electronic and crystallographic structures of Na sub(0.75)CoO sub(2). Systematic ab initiodensity functional calculations with DMOL3 package showed that the Ni and Zn were more stable when substituting Co with formation energy -2.35 eV, 2.08 eV when Fermi level equals the valence band maximum. While Eu is more stable when it substitutes Na having a formation energy of -2.64 eV. As these results show great harmony with existing experimental data, they provide new insights into the fundamental principle of dopant selection for manipulating the physical properties in the development of high performance sodium cobaltate based multifunctional materials.
ISSN:2046-2069
2046-2069
DOI:10.1039/C2RA22514J