Significant increase of Curie temperature in nano-scale BaTiO{sub 3}
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Advanced Materials (MOE), Tsinghua University, Beijing 100084 (China)
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)
The low Curie temperature (T{sub c} = 130 °C) of bulk BaTiO{sub 3} greatly limits its applications. In this work, the phase structures of BaTiO{sub 3} nanoparticles with sizes ranging from 2.5 nm to 10 nm were studied at various temperatures by using aberration-corrected transmission electron microscopy (TEM) equipped with an in-situ heating holder. The results implied that each BaTiO{sub 3} nanoparticle was composed of different phases, and the ferroelectric ones were observed in the shells due to the complicated surface structure. The ferroelectric phases in BaTiO{sub 3} nanoparticles remained at 600 °C, suggesting a significant increase of T{sub c}. Based on the in-situ TEM results and the data reported by others, temperature-size phase diagrams for BaTiO{sub 3} particles and ceramics were proposed, showing that the phase transition became diffused and the T{sub c} obviously increased with decreasing size. The present work sheds light on the design and fabrication of advanced devices for high temperature applications.
- OSTI ID:
- 22310709
- Journal Information:
- Applied Physics Letters, Vol. 105, Issue 18; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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