Presentation is loading. Please wait.

Presentation is loading. Please wait.

Yokohama National University H.Nakatsugawa, H.M.Jeong and K.Nagasawa

Published bySaija Halttunen Modified over 5 years ago

Similar presentations

Presentation on theme: "Yokohama National University H.Nakatsugawa, H.M.Jeong and K.Nagasawa"— Presentation transcript:

1 Yokohama National University H.Nakatsugawa, H.M.Jeong and K.Nagasawa
Thermoelectric properties and crystal structures in Y doped Ca3Co4O9 Yokohama National University H.Nakatsugawa, H.M.Jeong and K.Nagasawa

2 Outline Introduction Experimental Results and Discussion Summary
Resistivity & Seebeck coefficient Thermoelectric property & crystal structure Magnetic susceptibility & valence state of Co Powder neutron diffraction data Modulation of Co-O bond distances Summary

3 Introduction 15mΩcm 130μV/K 0.98W/mK
J.Sugiyama et al. : Phys.Rev.B 68 (2003) Y.Miyazaki et al : Solid State Ionics 172 (2004)

4 Experimental Solid-State reaction method ～ 85% Theoretical density
Calcination in air at 920℃ Cold Isostatic Press (CIP) at 200MPa Sintered in O2 at 920℃ ～ 85% Theoretical density Magnetic properties Magnetic susceptibility at 10Oe : 2K ～ 350K Powder Neutron Diffraction Thermoelectric properties Rietveld refinement using PREMOS91 Crystal structures using PRJMS Interatomic distance plots using MODPLR Electrical resistivity : 80K ～ 800K Seebeck coefficient : 80K ～ 800K

5 Resistivity & Seebeck coefficient

6 Thermoelectric property & crystal structure

7 Magnetic susceptibility & valence state of Co
[(Ca0.99Y0.01)2CoO3.20]0.62CoO2 [(Ca0.98Y0.02)2CoO3.21]0.62CoO2 [(Ca0.97Y0.03)2CoO3.18]0.62CoO2 [(Ca0.96Y0.04)2CoO3.21]0.62CoO2

8 Powder neutron diffraction data：pre-modulation
Rwp = 12.39% x=0.02 0050 0010 0030 0020

9 Powder neutron diffraction data：after-modulation
Rwp = 5.91% x=0.02 0050 0010 0030 0020

10 Modulation of Co-O bond distances (1)
x=0 x=0.01 x=0.02 x=0.03 x=0.04

11 Modulation of Co-O bond distances (2)
x=0 x=0.01 x=0.02 x=0.03 x=0.04

12 Modulation of Co-O bond distances (3)
x=0 x=0.01 x=0.02 x=0.03 x=0.04

13 Y-doping is an effective method to improve TE performance of Ca3Co4O9
Summary The valence state of Co ions in Y doped Ca3Co4O9 Co3.2+ in CoO2 sheet Co3.6+ in RS-type BL A broad minimum at 100K and a broad maximum at 350K ～ 600K in ρ(T) curve Incommensurate SDW transition below TSDWon = 100K Spin-state transition below TSSon = 600K Y-doping is an effective method to improve TE performance of Ca3Co4O9

Download ppt "Yokohama National University H.Nakatsugawa, H.M.Jeong and K.Nagasawa"

Similar presentations

Level Splitting in Frustrated non-Kramers doublet systems Collin Broholm and Joost van Duijn Department of Physics and Astronomy Johns Hopkins University.

Level Splitting in Frustrated non-Kramers doublet systems Collin Broholm and Joost van Duijn Department of Physics and Astronomy Johns Hopkins University.
Thermoelectric properties in the series Ag x TiS 2 Tristan Barbier, Marine Beaumale, Oleg Lebedev, Emmanuel Guilmeau, Yohann Bréard, Antoine Maignan

Thermoelectric properties in the series Ag x TiS 2 Tristan Barbier, Marine Beaumale, Oleg Lebedev, Emmanuel Guilmeau, Yohann Bréard, Antoine Maignan
Ivane Javakhishvili Tbilisi State University Institute of Condensed Matter Physics Giorgi Khazaradze M Synthesis and Magnetic Properties of Multiferroic.

Ivane Javakhishvili Tbilisi State University Institute of Condensed Matter Physics Giorgi Khazaradze M Synthesis and Magnetic Properties of Multiferroic.
Pressure-Induced Hydrogen-dominant metallic state in Aluminum Hydride HAGIHARA Toshiya Shimizu-group Igor Goncharenko et al., Phy. Rev. Lett. 100, 045504.

Pressure-Induced Hydrogen-dominant metallic state in Aluminum Hydride HAGIHARA Toshiya Shimizu-group Igor Goncharenko et al., Phy. Rev. Lett. 100,
Chapter 4, Section 1 Ionic Bonds Thursday, December 3, 2009 Pages 114 -- 120.

Chapter 4, Section 1 Ionic Bonds Thursday, December 3, 2009 Pages
1 1.Introduction 2.Electronic properties of few-layer graphites with AB stacking 3.Electronic properties of few-layer graphites with AA and ABC stackings.

1 1.Introduction 2.Electronic properties of few-layer graphites with AB stacking 3.Electronic properties of few-layer graphites with AA and ABC stackings.
Kitaoka lab Itohara Keita

Kitaoka lab Itohara Keita
Understanding the Giant Seebeck Coefficient of MnO 2 Nanoparticles Costel Constantin James Madison University James Madison University, October 2012.

Understanding the Giant Seebeck Coefficient of MnO 2 Nanoparticles Costel Constantin James Madison University James Madison University, October 2012.
The Double Pervoskite NaTbMnWO 6 : A Likely Multiferroic Material † Alison Pawlicki, ‡ A. S. Sefat, ‡ David Mandrus † Florida State University, ‡ Oak Ridge.

The Double Pervoskite NaTbMnWO 6 : A Likely Multiferroic Material † Alison Pawlicki, ‡ A. S. Sefat, ‡ David Mandrus † Florida State University, ‡ Oak Ridge.
Short range magnetic correlations in spinel Li(Mn 0.976 Co 0.024 ) 2 O 4.

Short range magnetic correlations in spinel Li(Mn Co ) 2 O 4.
Electrons on a triangular lattice in Na-doped Cobalt Oxide Yayu Wang, Maw Lin Foo, Lu Li, Nyrissa Rogado, S. Watauchi, R. J. Cava, N.P.O. Princeton University.

Electrons on a triangular lattice in Na-doped Cobalt Oxide Yayu Wang, Maw Lin Foo, Lu Li, Nyrissa Rogado, S. Watauchi, R. J. Cava, N.P.O. Princeton University.
Semiconductors and Diodes

Semiconductors and Diodes
THE SEEBECK COEFFICIENT Anthony Rice MTRL 286K 12/15/14.

THE SEEBECK COEFFICIENT Anthony Rice MTRL 286K 12/15/14.
Magnetic properties of a frustrated nickel cluster with a butterfly structure Introduction Crystal structure Magnetic susceptibility High field magnetization.

Magnetic properties of a frustrated nickel cluster with a butterfly structure Introduction Crystal structure Magnetic susceptibility High field magnetization.
Applications and Processing of Ceramics

Applications and Processing of Ceramics
Thermoelectricity of Semiconductors

Thermoelectricity of Semiconductors
Ying Chen Los Alamos National Laboratory Collaborators: Wei Bao Los Alamos National Laboratory Emilio Lorenzo CNRS, Grenoble, France Yiming Qiu National.

Ying Chen Los Alamos National Laboratory Collaborators: Wei Bao Los Alamos National Laboratory Emilio Lorenzo CNRS, Grenoble, France Yiming Qiu National.
Copper based composite: L-Cop Cu High thermal Conductive Cu 2 O Low thermal expansive Anna malai Industrial Engineering Material Science.

Copper based composite: L-Cop Cu High thermal Conductive Cu 2 O Low thermal expansive Anna malai Industrial Engineering Material Science.
Anomalous transport properties of the half-metallic ferromagnets Co 2 TiSi, Co 2 TiGe and Co 2 TiSn by Joachim Barth, Gerhard H. Fecher, Benjamin Balke,

Anomalous transport properties of the half-metallic ferromagnets Co 2 TiSi, Co 2 TiGe and Co 2 TiSn by Joachim Barth, Gerhard H. Fecher, Benjamin Balke,
Nanostructured Materials for Thermoelectric Power Generation Richard B. Kaner 1, Sabah K. Bux 1,3, and Jean-Pierre Fleurial 3 1 Department of Chemistry.

Nanostructured Materials for Thermoelectric Power Generation Richard B. Kaner 1, Sabah K. Bux 1,3, and Jean-Pierre Fleurial 3 1 Department of Chemistry.

Similar presentations

Ads by Google