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Title: Thermoelectric properties of rhodates: layered beta SrRh 2O 4 and spinel ZnRh 2O 4

Abstract

Density functional calculations are used to obtain the electronic structure of {beta}-SrRh{sub 2}O{sub 4} in comparison with spinel ZnRh{sub 2}O{sub 4}. Both materials are band insulators, with substantial crystal field induced band gaps, reflecting strong transition-metal-O hybridization. However, due to the bonding topology in these materials, the valence bands are very narrow. This leads to high thermopowers within standard Boltzmann transport theory, and indicates that they can be the basis of good thermoelectric materials provided that they can be doped into metallic states with reasonable carrier mobility. In the case of {beta}-SrRh{sub 2}O{sub 4}, scattering due to Sr disorder is important. Also, again in {beta}-SrRh{sub 2}O{sub 4}, the band gap may be large enough to be of interest for photoelectrochemical H{sub 2} production.

Authors:
 [1];  [1];  [2];  [1]
  1. ORNL
  2. Central Michigan University, Mt. Pleasant
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
931690
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 75; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BONDING; CARRIER MOBILITY; CRYSTAL FIELD; ELECTRONIC STRUCTURE; FUNCTIONALS; HYBRIDIZATION; PRODUCTION; SCATTERING; SPINELS; THERMOELECTRIC MATERIALS; THERMOELECTRIC PROPERTIES; TOPOLOGY; TRANSPORT THEORY; VALENCE

Citation Formats

Wilson-Short, Gareth B, Singh, David J, Fornari, M., and Suewattana, Malliga. Thermoelectric properties of rhodates: layered beta SrRh2O4 and spinel ZnRh2O4. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.75.035121.
Wilson-Short, Gareth B, Singh, David J, Fornari, M., & Suewattana, Malliga. Thermoelectric properties of rhodates: layered beta SrRh2O4 and spinel ZnRh2O4. United States. doi:10.1103/PhysRevB.75.035121.
Wilson-Short, Gareth B, Singh, David J, Fornari, M., and Suewattana, Malliga. Mon . "Thermoelectric properties of rhodates: layered beta SrRh2O4 and spinel ZnRh2O4". United States. doi:10.1103/PhysRevB.75.035121.
@article{osti_931690,
title = {Thermoelectric properties of rhodates: layered beta SrRh2O4 and spinel ZnRh2O4},
author = {Wilson-Short, Gareth B and Singh, David J and Fornari, M. and Suewattana, Malliga},
abstractNote = {Density functional calculations are used to obtain the electronic structure of {beta}-SrRh{sub 2}O{sub 4} in comparison with spinel ZnRh{sub 2}O{sub 4}. Both materials are band insulators, with substantial crystal field induced band gaps, reflecting strong transition-metal-O hybridization. However, due to the bonding topology in these materials, the valence bands are very narrow. This leads to high thermopowers within standard Boltzmann transport theory, and indicates that they can be the basis of good thermoelectric materials provided that they can be doped into metallic states with reasonable carrier mobility. In the case of {beta}-SrRh{sub 2}O{sub 4}, scattering due to Sr disorder is important. Also, again in {beta}-SrRh{sub 2}O{sub 4}, the band gap may be large enough to be of interest for photoelectrochemical H{sub 2} production.},
doi = {10.1103/PhysRevB.75.035121},
journal = {Physical Review B},
number = 3,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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