resumo
Present work focuses on detailed temperature-dependent X-ray diffraction, Raman scattering, domain configuration, and photoluminescence (PL) studies in the (Ba0.85Ca0.15) (Zr0.10Ti0.90)O-3 (BCZT) ceramics. The comprehensive Raman spectroscopy analysis in the present work not only validates the presence of the intermediate orthorhombic phase in BCZT, but also provides evidence of another transition: rhombohedral R3c phase to R3m at low temperature. Temperature behaviour of the lowest frequency transverse optical mode (soft E (TO) phonon) and hard modes was studied. Temperature dependence of peak positions, intensities, and linewidths of Raman phonon modes signalled the presence of phase transitions near-50 +/- 5 degrees C, 0 +/- 5 degrees C, 35 +/- 5 degrees C and 110 +/- 10 degrees C. Evolution of domain morphology occurring at phase transitions above room temperature was studied by piezoresponse force microscopy technique. Analysis of PL spectra revealed disorder/heterogeneity in the sample and indicated the existence of self-trapped excitons. PL spectra are composed of four distinct colour components (-2.55eV:blue, -2.32eV:green, -2.08eV:orange and -1.78eV:red).
categoria
Materials Science, Ceramics
autores
Coondoo, I; Panwar, N; Krylova, S; Krylov, A; Alikin, D; Jakka, SK; Turygin, A; Shur, VY; Kholkin, AL
nossos autores
Projectos
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
agradecimentos
I.C. would like to thank financial assistance by national funds (OE), through FCT - Fundacao para a Ciencia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The authors would also like to acknowledge the Ural Center for Shared Use Modern nanotechnology, Ural Federal University, Russia and the Krasnoyarsk Regional Center of Research Equipment of Federal Research Center Krasnoyarsk Science Center SB RAS. The authors would like to thank Dr. E. Venkata Ramana, Department of Physics, University of Aveiro for the dielectric measurements. The work was supported by Government of the Russian Federation (Act 211, 440 Agreement 02.A03.21.0006).