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Title: High thermal insulation properties of A 2 FeCoO 6−δ (A = Ca, Sr)
Materials with low thermal conductivity are essential to providing thermal insulation to many technological systems, such as electronics, thermoelectrics and aerospace devices. Here, we report ultra-low thermal conductivity of two oxide materials. Sr 2 FeCoO 6−δ has a perovskite-type structure with oxygen vacancies. It shows a thermal conductivity of 0.5 W m −1 K −1 , which is lower than those reported for perovskite oxides. The incorporation of calcium to form Ca 2 FeCoO 6−δ , leads to a structural change and the formation of different coordination geometries around the transition metals. This structural transformation results in a remarkable enhancement of the thermal insulation properties, showing the ultra-low thermal conductivity of 0.05 W m −1 K −1 , which is one of the lowest values found among solid materials to date. A comparison to previously reported perovskite oxides, which show significantly inferior thermal insulation compared to our materials, points to the effect of oxygen-vacancies and their ordering on thermal conductivity.  more » « less
Award ID(s):
1943085
PAR ID:
10399625
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
10
Issue:
35
ISSN:
2050-7526
Page Range / eLocation ID:
12569 to 12573
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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