Effective Thermal Conductivity of SrBi$_4$Ti$_4$O$_{15}$-La$_{0.7}$Sr$_{0.3}$MnO$_3$ Oxide composite: Role of Particle Size and Interface Thermal Resistance
| Autor: | Krzysztof T. Wojciechowski, Artur Kosonowski, Piotr Wyzga, Ashutosh Kumar |
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| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Condensed Matter - Materials Science Materials science Thermal resistance Composite number Materials Science (cond-mat.mtrl-sci) FOS: Physical sciences 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences symbols.namesake Thermal conductivity Phase (matter) 0103 physical sciences Thermoelectric effect Materials Chemistry Ceramics and Composites symbols Particle size Composite material 0210 nano-technology Debye model Perovskite (structure) |
| DOI: | 10.48550/arxiv.2009.02218 |
| Popis: | We present a novel approach to reduce the thermal conductivity ($\kappa$) in thermoelectric composite materials using acoustic impedance mismatch and the Debye model. Also, the correlation between interface thermal resistance (R$_{int}$) and the particle size of the dispersed phase on the k of the composite is discussed. In particular, the $\kappa$ of an oxide composite which consists of a natural superlattice Aurivillius phase (SrBi$_4$Ti$_4$O$_{15}$) as a matrix and perovskite (La$_{0.7}$Sr$_{0.3}$MnO$_3$) as a dispersed phase is investigated. A significant reduction in the $\kappa$ of composite, even lower than the $\kappa$ of the matrix when the particle size of La$_{0.7}$Sr$_{0.3}$MnO$_3$ is smaller than the Kapitza radius (a$_K$) is observed, depicting that R$_{int}$ dominates for particle size lower than a$_K$ due to increased surface to volume ratio. The obtained results have the potential to provide new directions for engineering composite thermoelectric systems with desired thermal conductivity and promising in the field of energy harvesting. Comment: 21 pages, 8 Figures, 5 Tables |
| Databáze: | OpenAIRE |
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