Thermoelectric properties of Nb-doped SrTiO3 films prepared by co-sputtering
| Autor: | Hyungtak Seo, Jinseo Kim, Minhwan Ko, Le Thai Duy, Sang Yeon Lee |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Niobium chemistry.chemical_element Clay industries. Ceramics. Glass 02 engineering and technology doping thermoelectric 01 natural sciences srtio3 Thermoelectric figure of merit Sputtering 0103 physical sciences Thermoelectric effect 010302 applied physics business.industry Doping 021001 nanoscience & nanotechnology TP785-869 Nb doped chemistry Ceramics and Composites Optoelectronics 0210 nano-technology business niobium co- sputtering |
| Zdroj: | Journal of Asian Ceramic Societies, Vol 8, Iss 4, Pp 1135-1146 (2020) |
| ISSN: | 2187-0764 |
| Popis: | SrTiO3 (STO), a member of perovskite structure materials, exhibits a large thermoelectric figure of merit at high temperatures. Theoretically, its property can be significantly improved by niobium (Nb) dopant. So far, the synthesis method of Nb-doped STO and the evaluation of their thermoelectric properties at low temperatures have not been explored fully. Here, our development of highly Nb-doped STO films using the co-sputtering with STO and Nb targets at room temperature (298 K) is introduced. A rapid annealing process (30 min, at 1073 K) is applied to further crystallize these films. Through measurements at 300 ~ 600 K, a significant improvement of the thermoelectric performance of STO films upon 2% Nb-doping is observed. Particularly, the working temperature of Nb-doped STO begins at 350 K instead of 475 K of STO. The figure of merit of Nb-doped STO can reach 0.53 at 600 K. Through TEM-EDS and TOF-SIMS characterizations, the mechanism of Nb-doping effect on the STO properties is revealed and discussed in detail. Our doping method at room temperature is potential, as compared to other synthesis methods, regarding the uniform incorporation of Nb dopants in STO films. Overall, our work showed another way for further improvement of perovskite-based thermoelectric materials. |
| Databáze: | OpenAIRE |
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