Study of the morphotropic phase boundary in the lead-free Na_1/2Bi_1/2TiO₃-BaTiO₃ system by Raman spectroscopy

Abstract

Lead-free piezoelectric (100-x)Na1/2Bi1/2TiO3-xBaTiO3 solid solution ceramics are investigated by Raman spectroscopy and Xray diffraction over a composition range of 0 ≤ x ≤ 10. Distinct changes in the Raman spectra and X-ray diffraction patterns were discussed in the light of a rhombohedral to tetragonal phase transition. The dominant bands in the Raman spectra were analyzed by observing the changes in their respective peak positions, widths and intensities as the composition increased. Based on these results, it is suggested that the morphotropic phase boundary in the studied system lies at the composition of x ≈ 5.5. This is further evidenced by the X-ray diffraction analysis.

Structural complexity of(Na0.5Bi0.5)TiO3Eerd1, Damjanović2, Klein3 et al. 2010Phys. Rev. B280141012View full textAdd to dashboardCite

“…We do not assign here the normal-mode vibrations that are responsible for the Raman lines, but note that these are already discussed in the literature. 33 Simple inspection of the spectra shows clearly altered patterns between 5 and 6% BT, signalled here by (1) third pseudocubic phase; we will return to this point in connection with spectra from poled samples. Note that these spectra bear a very strong resemblance to those reported by Rout et al, 33 which confirmed the existence of the phase boundary near 6% marked in Fig.…”

Evolution of the crystalline structure in (Bi_0.5Na_0.5)_1-xBa_xTiO₃ thin films around the Morphotropic Phase Boundary

“…A significant controversy related to the MPB region for the BNBT composition is found in the literature (11)(12)(13)(14). Recent works, based on the variation of the electrical properties and in-situ synchrotron diffraction analysis, have positioned the MPB region for BNBT bulk ceramics for x values between 0.050 and 0.110, where the transition from the space group R3m to the P4mm one occurs (15).…”

Structural phase transition, optical and pyroelectric properties of lead-free single crystals

“…Three strong Raman bands appear in all the crystal plates, in which the shape, positions, intensity and bandwidth of the peaks exhibit great differences on the crystal orientations. The diffused Raman bands centered around 300, 560 ] stretching vibration and "soft mode" mixed by bending and stretching vibrations [5,7,18]. Fine Raman spectroscopy research indicates that the [TiO 6 ] octahedron vibrations are composed of six species of vibration modes [18].…”

“…The infrared-absorption band occurred around 630.6 cm 1 can be assigned to the "stretching" normal vibration of [Na With the demand for sustainable development of environmental protection and human society, development of lead-free piezoelectric materials that can replace hazardous lead-based Pb(Zr x Ti 1x )O 3 (PZT) piezoelectric ceramics has been research hot in piezoelectric application fields [1][2][3]. Among lead-free piezoelectric materials, (1x)(Na 1/2 Bi 1/2 ) TiO 3 -xBaTiO 3 (NBT-BT) solid solutions attract great research attention due to their excellent piezoelectric performance [4,5]. Since piezoelectric materials existence in crystallographically engineered single crystals exhibit more excellent piezoelectric properties, much work has been undertaken on the growth of high-quality and large-size NBT-BT single crystals [6,7].…”

“…Among lead-free piezoelectric materials, (1x)(Na 1/2 Bi 1/2 ) TiO 3 -xBaTiO 3 (NBT-BT) solid solutions attract great research attention due to their excellent piezoelectric performance [4,5]. Since piezoelectric materials existence in crystallographically engineered single crystals exhibit more excellent piezoelectric properties, much work has been undertaken on the growth of high-quality and large-size NBT-BT single crystals [6,7].…”