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In this study, we investigate the utility of Ca2FeMnO6-δand Sr2FeMnO6-δas materials with low thermal conductivity, finding potential applications in thermoelectrics, electronics, solar devices, and gas turbines for land and aerospace use. These compounds, characterized as oxygen-deficient perovskites, feature distinct vacancy arrangements. Ca2FeMnO6-δadopts a brownmillerite-type orthorhombic structure with ordered vacancy arrangement, while Sr2FeMnO6-δadopts a perovskite cubic structure with disordered vacancy distribution. Notably, both compounds exhibit remarkably low thermal conductivity, measuring below 0.50 Wm−1K−1. This places them among the materials with the lowest thermal conductivity reported for perovskites. The observed low thermal conductivity is attributed to oxygen vacancies and phonon scattering. Interestingly as SEM images show the smaller grain size, our findings suggest that creating vacancies and lowering the grain size or increasing the grain boundaries play a crucial role in achieving such low thermal conductivity values. This characteristic enhances the potential of these materials for applications where efficient heat dissipation, safety, and equipment longevity are paramount.
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Study of Thermal Insulation Nature of A2Fe2O6-δ (A and A’ = Ca, Sr)
Materials with low thermal conductivity have been used in thermoelectrics, electronics, solar devices, and land base and aerospace gas turbines to prevent heat dissipation and provide safety and longevity of equipment. We report Ca2Fe2O6-δ, and Sr2Fe2O6-δ for their low thermal conductivities. These compounds are vacancy-ordered oxygen-deficient perovskites but with different vacancy arrangements. Ca2Fe2O6-δ has a brownmillerite type structure while Sr2Fe2O6-δ has a different structure.
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- PAR ID:
- 10539336
- Publisher / Repository:
- Juniper Publishing
- Date Published:
- Journal Name:
- Engineering Technology Open Access Journal
- Edition / Version:
- 1
- Volume:
- 5
- Issue:
- 5
- ISSN:
- 2641-8185
- Page Range / eLocation ID:
- 1
- Subject(s) / Keyword(s):
- Thermal, Engineering Technology, Insulation, A2Fe2O6-δ
- Format(s):
- Medium: X Size: 1MB Other: 1
- Size(s):
- 1MB
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.19080/ETOAJ.2024.05.555671
