Effects from A-site substitution on morphotropic phase boundary and phonon modes of (Pb1–1.5xLax)(Zr0.42Sn0.40Ti0.18)O3 ceramics by temperature dependent Raman spectroscopy

AbstractDiscovery of two-dimensional (2D) topological insulators (TIs) demonstrates tremendous potential in the field of thermoelectric since the last decade. Here, we have synthesized 2D TI, Sb2Te3 of various thicknesses in the range 65–400 nm using mechanical exfoliation and studied temperature coefficient in the range 100–300 K using micro-Raman spectroscopy. The temperature dependence of the peak position and line width of phonon modes have been analyzed to determine the temperature coefficient, which is found to be in the order of 10–2 cm−1/K, and it decreases with a decrease in Sb2Te3 thickness. Such low-temperature coefficient would favor to achieve a high figure of merit (ZT) and pave the way to use this material as an excellent candidate for thermoelectric materials. We have estimated the thermal conductivity of Sb2Te3 flake with the thickness of 115 nm supported on 300-nm SiO2/Si substrate which is found to be ~ 10 W/m–K. The slightly higher thermal conductivity value suggests that the supporting substrate significantly affects the heat dissipation of the Sb2Te3 flake.

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MORPHOTROPIC PHASE BOUNDARY IN (Na0.5 Bi0.5)TiO₃−BaTiO₃ LEAD FREE SYSTEM: XRD AND RAMAN SPECTROSCOPY STUDIES

Ceramics - Silikaty ◽

10.13168/cs.2016.0031 ◽

2016 ◽

pp. 205-209 ◽

Cited By ~ 1

Author(s):

Hamza Lidjici

Keyword(s):

Raman Spectroscopy ◽

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Lead Free ◽

Free System ◽

Spectroscopy Studies

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Local structural phenomena in pure and Ru-doped0.9PbZn1/3Nb2/3O3−0.1PbTiO3near the morphotropic phase boundary as revealed by Raman spectroscopy

Physical Review B ◽

10.1103/physrevb.83.214104 ◽

2011 ◽

Vol 83 (21) ◽

Cited By ~ 44

Author(s):

N. Waeselmann ◽

B. Mihailova ◽

B. J. Maier ◽

C. Paulmann ◽

M. Gospodinov ◽

...

Keyword(s):

Raman Spectroscopy ◽

Phase Boundary ◽

Morphotropic Phase Boundary

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Phase Diagram of the W-doped Pb(Zn1/3Nb2/3)O3–BaTiO3– PbTiO3 System Around a Morphotropic Phase Boundary Composition

Journal of Materials Research ◽

10.1557/jmr.2002.0160 ◽

2002 ◽

Vol 17 (5) ◽

pp. 1085-1091 ◽

Cited By ~ 1

Author(s):

W. Z. Zhu ◽

M. Yan ◽

A. L. Kholkin ◽

P. Q. Mantas ◽

J. L. Baptista

Keyword(s):

High Temperature ◽

Phase Boundary ◽

Morphotropic Phase Boundary ◽

Room Temperature ◽

X Ray Diffraction ◽

X Ray ◽

Electrical Neutrality ◽

Phase Boundary Composition ◽

A Site ◽

Successive Phase

The morphotropic phase boundary (MPB) composition that is characterized by the coexistence of rhombohedral and tetragonal phases in the Pb(Zn1/3Nb2/3)O3–BaTiO3– PbTiO3 system was modified by W-doping at the B site of a perovskite structural block. To maintain the electrical neutrality, creation of A-site vacancies was intentionally introduced in the formulation of the examined compositions. Incorporation of W ions was revealed to stabilize the tetragonal phase against the rhombohedral one, shifting the MPB toward the PZN-rich end at room temperature. High-temperature x-ray diffraction examination in combination with dielectric measurements discloses two successive phase transitions as a sample is cooled from high temperature, namely, paraelectric cubic to ferroelectric rhombohedral followed by ferroelectric rhombohedral to ferroelectric tetragonal. W addition appears to suppress the first transition while promoting the second one.

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