About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
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Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials
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Presentation Title |
Colossal Enhancement of the Thermoelectric Power Factor of La0.7Ca0.2Ni0.25Ti0.75CoO3 Epitaxial Thin Films by Exsolution |
Author(s) |
Mohammad El Loubani, Gene Yang, Tae-sik Oh, Dongkyu Lee |
On-Site Speaker (Planned) |
Mohammad El Loubani |
Abstract Scope |
Transition metal oxides (TMOs) show great promise for high-temperature thermoelectric (TE) applications. The key challenge in developing oxide TE materials with superior performance is to tailor interconnected physical parameters including the electronic conductivity and thermopower. Exsolution is an emerging nanostructuring technique that can release nanoparticles from the B-site of TMO to the surface. However, the influence of exsolution on TE properties of TMOs is barely understood. Here, we show the effect of exsolution on physical and chemical properties of TMOs by employing epitaxial La0.7Ca0.2Ti0.75Ni0.25O3 (LCNT) thin films as a model system. The results of Mott-Schottky reveal that exsolution decreases mobility and increases the effective mass of charge carriers. This led to a decrease in the electronic conductivity and an increase in thermopower. However, the enhancement of the thermopower overcomes the decrease in electronic conductivity which leads to an overall enhancement of TE power factor by almost 2 orders of magnitude. |