Relaxor Behavior of Lead-Free Nonstoichiometric (Na_0.48-xK_0.48-xLi_0.04)Nb_0.89-xTa_0.05Sb_0.06O₃-xSrTiO₃Ceramics

Abstract

In the present work, the effects of SrTiO3 are investigated for nonstoichiometric (Na0.48-xK0.48-xLi0.04Srx)Nb0.89-xTixTa0.05Sb0.06O3 lead-free relaxor ferroelectric ceramics synthesized using a solid-state reaction method. The empirical law, two ordering models, the spin-glass model and the Curie–Weiss law are used to appraise the dielectric behavior. According to the fitting results and experimental data, the dielectric properties exhibit strong temperature-dependent characteristics with increasing amounts of SrTiO3 dopant, which is attributed to the disorder of the cations being significantly enhanced.

Phase Structure Transformations and Electrical Properties of (Na0.52K0.4425)(Nb0.8925Sb0.07)O3–0.0375LiTaO3Ceramics According to Sintering Temperature

“…Apparently, the DPT degree is smaller and the normal ferroelectric characteristic is more obvious when the values of ξ and are smaller. 17,18 In order to estimate the experimental data, only the paraelectric regions are used for fitting with Eq. 1, the experimental data and the fitting curves of which are shown in Fig.…”

Improvement of Energy Storage Properties of NaNbO3-Based Ceramics through a Relaxation Strategy

“…The value of t 0.9 (the time required to release 90% of the stored The decrease of W d might be related to the decrease of polarization at high temperature. 14,36,45 As the temperature increased from 40 °C to 140 °C, t 0.9 decreased from 0.3 μs to 0.11 μs due to the decrease of W d . The x = 0.2 ceramics exhibit stable current peak (I max ⩾ 10 A), higher discharge density (W d ⩾ 0.668 J cm −3 ) and shorter discharge time (t 0.9 ⩽ 0.3 μs), these results indicate that x = 0.2 ceramics are expected to be candidates for pulsed energy storage capacitors.…”

“…13 The RFE possesses short-range order and highly dynamic polar nano-regions (PNRs) that are very sensitive to apply electric fields, resulting in low P r and slim P-E loops. 14 A large number of lead-free relaxor antiferroelectric materials have been recently developed. Shi et al introduced the relaxant Bi(Zn 0.5 Ti 0.5 )O 3 (BZT) into NaNbO 3 to reduce the sintering temperature and improve the breakdown strength, a high W rec of 2.1 J cm −3 and a high η of 76% were obtained under the electric field condition of 200 kV cm −1 .…”

Effects of CuO Sintering Aids on Microstructure and Electric Properties for (Na0.48K0.473Li0.04Sr0.007) (Nb0.883Ta0.05Sb0.06Ti0.007)O3 Ceramics

“…In Figure 3, the peak dielectric constants corresponding to the phase transition are decreased and the dielectric peaks seem broader when the amounts of CuO additives are increased. The broad dielectric peaks always show more diffused phase transition behavior and relate to the Curie-Weiss law [30][31][32]. The Curie-Weiss law is usually used to describe the dielectric behaviour.…”

“…The dielectric behavior follows the Curie-Weiss law in the paraelectric region at enough high temperature, but it deviates from the Curie-Weiss law at lower temperatures (but still above T m ). T B is the temperature at which the deviation begins, and the local order polarization is induced [30].…”