Structure and Dielectric Studies of Sn4+/Er3+ co-doped BaTiO3 Nano-Powders

R. Mahania, O. El-Sayedb, S.K. El-Mahyb, I.K. Battishac aMicrowave Physics and Dielectrics Dept., National Research Centre, 33 El Bohouth Str., 12622 Giza, Egypt bPhysics Department, Faculty of Women for Arts, Science and Education, Ain Shams University, Cairo, Egypt cSolid State Physics Dept., National Research Centre, 33 El Bohouth Str., 12622 Giza, Egypt

Received: November 27, 2019; revised version December 23, 2019; in final form December 24, 2019

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Nanocrystalline barium titanate (BTO3) powders annealed at 1050° for 4 h, were synthesized using the sol-gel method and the effects of Sn4+/Er3+ co-doping (BTSO3:2Er) on microstructure and dielectric properties of BTO3 powders, were investigated. The crystalline structure, microstructure, molecular structure, and dielectric properties were investigated using X-ray powder diffraction, field emission scanning electron microscope, with energy dispersive X-ray analysis, the Fourier transform infra-red spectroscopy, and dielectric spectrometer. X-ray powder diffraction analysis confirmed the formation of both BTO3 and BTSO3:2Er in a single tetragonal phase. For BTSO3:2Er sample, the particle size decreased from 64 for pure BTO3 to 57.11 nm for BTSO3:2Er, inhibiting grain growth upon co-doping with Sn4+/Er3+ ions. Further, according to field emission scanning electron microscope observations, the Fourier transform infra-red spectroscopy analysis showed a new band assigned to M-O. Correspondingly, BTSO3:2Er showed an anomaly relaxation peak whose maximum was positioned at temperature value (174°) higher than the Curie temperature (TC) according to permittivity measurements. Its TC shifted from 125 to 103° and permittivity considerably increased to become ten times greater than that of pure BTO3, revealing enhancements of dielectric properties upon doping with Sn4+/Er3+ ions. Also, AC conductivity for BTSO3:2Er sample considerably increased due to the formation of excess oxygen vacancies.

DOI:10.12693/APhysPolA.137.410 topics: nanopowder, X-ray diffraction, barium titanate, dielectric properties