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Dielectric properties of Y and Nb co-doped TiO₂ ceramics.

ABSTRACT: In this work, the (Y_0.5Nb_0.5)_xTi_1-xO₂ (x?=?0.001, 0.01, 0.02, 0.04, 0.06 and 0.1) ceramics (as called YNTO) were fabricated by synthesized through a standard solid-state reaction. As revealed by the X-ray diffraction (XRD) spectra, the YNTOs exhibit tetragonal rutile structure. Meanwhile, the grain size of YNTO ceramics increased and then decreased with the increase of x value, and the largest value reached when x?=?0.02. All the YNTO samples display colossal permittivity (~10²-10⁵) over a wide temperature and frequency range. Moreover, the optimal ceramic, (Y_0.5Nb_0.5)_0.02Ti_0.98O₂, exhibits high performance over a broad temperature range from 20?°C to 180?°C; specifically, at 1?kHz, the dielectric constant and dielectric loss are 6.55?×?10⁴ and 0.22 at room temperature, and they are 1.03?×?10⁵ and 0.11 at 180?°C, respectively.

SUBMITTER: Wang X

PROVIDER: S-EPMC5561205 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Dielectric properties of Y and Nb co-doped TiO2 ceramics.

Wang Xianwei X Zhang Bihui B Xu Linhai L Wang Xiaoer X Hu Yanchun Y Shen Gaohang G Sun Lingyun L

Scientific reports 20170817 1

In this work, the (Y0.5Nb0.5)xTi1-xO2 (x = 0.001, 0.01, 0.02, 0.04, 0.06 and 0.1) ceramics (as called YNTO) were fabricated by synthesized through a standard solid-state reaction. As revealed by the X-ray diffraction (XRD) spectra, the YNTOs exhibit tetragonal rutile structure. Meanwhile, the grain size of YNTO ceramics increased and then decreased with the increase of x value, and the largest value reached when x = 0.02. All the YNTO sample ...[more]

PMID: 28819129

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