resumo
Pristine and 0.04 wt.% Pr6O11 substituted Ba0.85Ca0.15Zr0.1Ti0.9O3 (BCZT) lead-free ceramics have been synthesized by the conventional solid-state reaction method at 1450 and 1300 degrees C sintering temperatures, respectively. The synthesized compounds were characterized by their structural, microstructural, piezoelectric, dielectric and luminescent properties. Coexistence of tetragonal and orthorhombic phases was observed for both pure and Pr doped BCZT compounds. Higher piezoelectric coefficient (d(33)) similar to 220 pC/N, maximum dielectric constant (epsilon(m)) similar to 4204 and minimum dielectric loss (tan delta) similar to 0.025 were obtained for Pr doped compound as compared to 180 pC/N, 3353 and 0.034 values, respectively, for the undoped BCZT ceramics. Strong photoluminescence emission spectra consisting of blue (489 nm), green (530 nm) and red (602 nm) light emissions were observed in Pr doped compound. Our results demonstrate that Pr6O11 addition in BCZT ceramics is helpful in increasing the electrical properties, inducing the luminescent effect and simultaneously reducing the sintering temperatures of BCZT. The results have been understood in the light of Pr3+ ions occupying the Ti4+-sites.
palavras-chave
LUMINESCENCE; TRANSITIONS
categoria
Engineering; Materials Science; Physics
autores
Ramovatar; Coondoo, I; Satapathy, S; Kumar, N; Panwar, N
nossos autores
Indrani Coondoo
Investigadoragradecimentos
The author Ramovatar would like to thank the University Grants Commission, New Delhi for providing the Rajiv Gandhi National Fellowship (RGNF). Indrani Coondoo acknowledges the financial support from FCT, Portugal, through SFRH/BPD/81032/2011. The authors are thankful to Dr. Saral Kumar Gupta, Department of Physics, Banasthali Vidyapeeth Rajasthan India for help in acquiring the micrographical images of the compounds.