Investigation of solid solution of barium–strontium orthotitanates of the type, Ba2–𝑥Sr𝑥TiO4 (0 ≤ 𝑥 ≤ 2), show that pure phases exist only for the end members, Ba2TiO4 and Sr2TiO4, crystallizing in the 𝛽-K2SO4 and K2NiF4 structures, respectively. The intermediate compositions (till 𝑥 ≤ 1) lead to a biphasic mixture of two Ba2TiO4-type phases (probably through a spinodal decomposition) with decreasing lattice parameters, indicating Sr-substitution in both the phases. For 𝑥 > 1, Sr2TiO4 along with a secondary phase is obtained. The dielectric constant and dielectric loss were found to decrease with Sr substitution till the nominal composition of 𝑥 = 1. However, pure Sr2TiO4 shows higher dielectric constant compared to the solid solution composition. Sr2TiO4 shows very high temperature stability of the dielectric constant.
Volume 45, 2022
Continuous Article Publishing mode
Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
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