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Title: Microstructural analysis and thermoelectric properties of Sn-Al co-doped ZnO ceramics

Abstract

Sn-Al co-doped polycrystalline ZnO ceramics were prepared by sintering in air. Phase and microstructure analysis was performed by X-ray diffraction and SEM-EDS and thermoelectric properties were measured. XRD analysis showed a ZnO primary phase as well as secondary phase peaks due to the formation of a Zn{sub 2}SnO{sub 4} spinel phase or SnO{sub 2}(ZnO:Sn-Al){sub m} intergrowth phase. SEM analysis revealed a dense microstructure with a small number of nanometric pores, consistent with the measured density of 5.48 g/cm{sup 3}. An activated electrical conductivity characteristic of a semiconducting material was observed as well as a negative Seebeck coefficient with both values increasing in absolute value from RT to 730 °C. The power factor had a maximum value of 3.73×10{sup −4} W m{sup −1} K{sup −2} at 730 °C. Thermal conductivity measurements showed a significant reduction over the measured temperature range compared to undoped ZnO. This could be attributed to grain size reduction, the formation of a nanoscale secondary phase or a reduction in crystallinity caused by Sn-Al co-doping. A maximum ZT of 0.06 was obtained at 750 °C for the Sn-Al co-doped ZnO ceramics.

Authors:
; ; ;  [1]; ;  [2]; ;  [3]
  1. Institute of Engineering Innovation, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)
  2. National Institute of Materials Science (NIMS) 1-1 Namiki, Tsukuba 305-0044 (Japan)
  3. National Institute of Materials Science (NIMS), 1–2–1 Sengen, Tsukuba, 305–0047 (Japan)
Publication Date:
OSTI Identifier:
22608254
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1763; Journal Issue: 1; Conference: FMS2015: 2. international symposium on frontiers in materials science, Tokyo (Japan), 19-21 Nov 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM ADDITIONS; CERAMICS; COMPARATIVE EVALUATIONS; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; GRAIN SIZE; MICROSTRUCTURE; NANOSTRUCTURES; POLYCRYSTALS; POWER FACTOR; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR MATERIALS; SINTERING; SPINELS; THERMAL CONDUCTIVITY; THERMOELECTRIC PROPERTIES; TIN ADDITIONS; TIN OXIDES; X-RAY DIFFRACTION; ZINC OXIDES

Citation Formats

Hoemke, Joshua, E-mail: jhoemke@sigma.t.u-tokyo.ac.jp, Tochigi, Eita, Shibata, Naoya, Ikuhara, Yuichi, Khan, Atta Ullah, Mori, Takao, Yoshida, Hidehiro, and Sakka, Yoshio. Microstructural analysis and thermoelectric properties of Sn-Al co-doped ZnO ceramics. United States: N. p., 2016. Web. doi:10.1063/1.4961357.
Hoemke, Joshua, E-mail: jhoemke@sigma.t.u-tokyo.ac.jp, Tochigi, Eita, Shibata, Naoya, Ikuhara, Yuichi, Khan, Atta Ullah, Mori, Takao, Yoshida, Hidehiro, & Sakka, Yoshio. Microstructural analysis and thermoelectric properties of Sn-Al co-doped ZnO ceramics. United States. doi:10.1063/1.4961357.
Hoemke, Joshua, E-mail: jhoemke@sigma.t.u-tokyo.ac.jp, Tochigi, Eita, Shibata, Naoya, Ikuhara, Yuichi, Khan, Atta Ullah, Mori, Takao, Yoshida, Hidehiro, and Sakka, Yoshio. 2016. "Microstructural analysis and thermoelectric properties of Sn-Al co-doped ZnO ceramics". United States. doi:10.1063/1.4961357.
@article{osti_22608254,
title = {Microstructural analysis and thermoelectric properties of Sn-Al co-doped ZnO ceramics},
author = {Hoemke, Joshua, E-mail: jhoemke@sigma.t.u-tokyo.ac.jp and Tochigi, Eita and Shibata, Naoya and Ikuhara, Yuichi and Khan, Atta Ullah and Mori, Takao and Yoshida, Hidehiro and Sakka, Yoshio},
abstractNote = {Sn-Al co-doped polycrystalline ZnO ceramics were prepared by sintering in air. Phase and microstructure analysis was performed by X-ray diffraction and SEM-EDS and thermoelectric properties were measured. XRD analysis showed a ZnO primary phase as well as secondary phase peaks due to the formation of a Zn{sub 2}SnO{sub 4} spinel phase or SnO{sub 2}(ZnO:Sn-Al){sub m} intergrowth phase. SEM analysis revealed a dense microstructure with a small number of nanometric pores, consistent with the measured density of 5.48 g/cm{sup 3}. An activated electrical conductivity characteristic of a semiconducting material was observed as well as a negative Seebeck coefficient with both values increasing in absolute value from RT to 730 °C. The power factor had a maximum value of 3.73×10{sup −4} W m{sup −1} K{sup −2} at 730 °C. Thermal conductivity measurements showed a significant reduction over the measured temperature range compared to undoped ZnO. This could be attributed to grain size reduction, the formation of a nanoscale secondary phase or a reduction in crystallinity caused by Sn-Al co-doping. A maximum ZT of 0.06 was obtained at 750 °C for the Sn-Al co-doped ZnO ceramics.},
doi = {10.1063/1.4961357},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1763,
place = {United States},
year = 2016,
month = 8
}
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