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Title: Thermoelectric and mechanical properties on misch metal filled p-type skutterudites Mm{sub 0.9}Fe{sub 4−x}Co{sub x}Sb{sub 12}

Most of the recent work focused on improving the dimensionless figure-of-merit, ZT, of p-type skutterudites uses one or two fillers to tune the electrical and thermal properties. Considering the fact that the different fillers with varying atomic mass and ionic radii can vibrate with different amplitudes to scatter phonons of different mean free paths, we synthesized misch metal filled p-type skutterudites Mm{sub 0.9}Fe{sub 4−x}Co{sub x}Sb{sub 12} (where Mm is La{sub 0.25}Ce{sub 0.5}Pr{sub 0.05}Nd{sub 0.15}Fe{sub 0.03}, called misch metal). The samples were synthesized by hot pressing nano-powder made by ball milling the annealed ingot of Mm{sub 0.9}Fe{sub 4−x}Co{sub x}Sb{sub 12} with varying concentration of cobalt, x. By tuning the Fe/Co ratio, we achieved a thermal conductivity of ∼2 W m{sup −1} K{sup −1} at room temperature and ∼2.3 W m{sup −1} K{sup −1} at about 530 °C and a power factor of ∼30 μW cm{sup −1} K{sup −2} at about 425 °C in Mm{sub 0.9}Fe{sub 3.1}Co{sub 0.9}Sb{sub 12}, leading to a peak ZT ∼1.1 at about 425 °C. The nano-indentation experiment reveals that hardness and elastic modulus of the material is about 4.2 GPa and 116 GPa, respectively.
Authors:
; ; ; ;  [1] ; ;  [2]
  1. Department of Physics and Texas Center for Superconductivity, University of Houston, Texas 77204 (United States)
  2. Department of Mechanical Engineering, University of Houston, Texas 77204 (United States)
Publication Date:
OSTI Identifier:
22413061
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNEALING; ANTIMONIDES; CERIUM COMPOUNDS; COBALT; COBALT COMPOUNDS; CONCENTRATION RATIO; HARDNESS; HOT PRESSING; IRON COMPOUNDS; MEAN FREE PATH; MILLING; MISCH METAL; PHONONS; POWDERS; PRESSURE RANGE GIGA PA; P-TYPE CONDUCTORS; TEMPERATURE RANGE 0273-0400 K; THERMAL CONDUCTIVITY