Significant increase of Curie temperature in nano-scale BaTiO3

Abstract

Articles you may be interested inStructural and dielectric properties of laser ablated BaTiO3 films deposited over electrophoretically dispersed CoFe2O4 grains Raman spectroscopic study of Na1/2Bi1/2TiO3-x%BaTiO3 single crystals as a function of temperature and compositionThe low Curie temperature (T c ¼ 130 C) of bulk BaTiO 3 greatly limits its applications. In this work, the phase structures of BaTiO 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 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 3 nanoparticles remained at 600 C, suggesting a significant increase of T c . Based on the in-situ TEM results and the data reported by others, temperature-size phase diagrams for BaTiO 3 particles and ceramics were proposed, showing that the phase transition became diffused and the T c obviously increased with decreasing size. The present work sheds light on the design and fabrication of advanced devices for high temperature applications.

Flexible BaTiO3/PVDF gradated multilayer nanocomposite film with enhanced dielectric strength and high energy density

“…BTO nanoparticles with an average diameter as small as 8 nm were homogeneously dispersed in this sol from the inserted TEM observation. 19 Thus these 8-nm BTO nanoparticles are capable to show higher spontaneous polarizations and have the potential to provide enhanced electric displacement in the multilayer nanocomposite. 14 Instead, Li et al has observed multiphase coexistence and a superior high Curie temperature for the 2.5 nm BTO nanoparticles by using aberration-corrected transmission electron microscopy under an in-situ heating holder.…”

Innovative architectures in ferroelectric multi-materials: Chemistry, interfaces and strain

“…[4][5][6][7] Ferroelectric nanopowders with a grain size below 20 nm are now available but the processing routes used are mainly focused on barium titanate (BT). [8][9][10] Producing well-crystallized sub-50 nm grains of narrow size distribution and over a whole solid solution is still a challenge. In addition, several works in literature, underline the spreading of the permittivity values and highlight the strong influence of both synthesis and sintering methods.…”

Measurement of Barium Ion Displacement Near Surface in a Barium Titanate Nanoparticle by Scanning Transmission Electron Microscopy

“…In particular, precision in the atomic position determination has been improved to picometer level in recent years (Borisevich et al, 2012;Jia et al, 2008;Polking et al, 2012;Yadav et al, 2016;Yankovich et al, 2014). Such structural characterization has been reported for example by Polking et al (2012) with high-resolution TEM and electron holography and by Li et al (2014) with high-resolution TEM under in-situ heating. Polking et al (2012) has visualized the polarization distribution within NP and reported that BTO NP with the size below 10 nm exhibited ferroelectricity at room temperature.…”

“…Polking et al (2012) has visualized the polarization distribution within NP and reported that BTO NP with the size below 10 nm exhibited ferroelectricity at room temperature. On the other hand, Li et al (2014) has reported that BTO NPs with the sizes ranging from 2.5 nm to 10 nm composed of multiple phases and the increment of Curie temperature up to 600°C. Even though these studies have demonstrated structural distribution in NPs, structure of NP with the size larger than 20 nm may be needed since such larger NP was not investigated in the previous studies Polking et al, 2012).…”