Investigation of the dielectric properties of MnO-additive Pb(Fe2∕3W1∕3)–PbTiO3 relaxors using the spin-glass model

Abstract

The low-field dielectric responses of pure and 0.15wt.% MnO-added (1−x)Pb(Fe2∕3W1∕3)O3–xPbTiO3 [(1−x)PFW–xPT] were investigated with the empirical model, the Curie–Weiss law and the spin-glass model. According to the experimental data and the fitting results, we conclude that (1) the lattice structure is changed and the electron compensation is induced with MnO addition. (2) The dielectric behaviors obey the Curie–Weiss law as the temperature is much far above Tm for all samples. (3) TCW, the temperature at which the dielectric behaviors deviate from the Curie–Weiss law, is higher and the diffuse phase characteristic is more obvious as decreasing PbTiO3 content or adding MnO. (4) The tailed temperature-dependent local order parameters, which are derived from the spin-glass model and the experimental results, for more diffuse phase transition relaxors show higher thermal stability in the spontaneous polarization microregions. (5) The temperature-dependent local ordering parameters change from a long-range-ordered ferroelectric state to a short-range-ordered relaxor with decreasing the PbTiO3 content or adding MnO.

Effects of the sintering temperature on the diffused phase transition and the spin-glassy behavior in Pb0.95La0.05(Fe2/3W1/3)0.65Ti0.35O3 ceramics

“…In our previous reports, authors successfully evaluate the temperature-dependent local order parameters by using the spin-glass model in Pb͑Fe 2/3 W 1/3 ͒O 3 -PbTiO 3 ͑PFW-PT͒ based ceramics to describe the sharp temperature-dependent local order parameters with the long range order ͑LRO͒ state and sharp DPT ferroelectric characteristics. 6,20,21 These results are similar to other reports of Mitoseriu et al, Viehland et al,and Chang et al 18,19,22,23 Pb͑Fe 2/3 W 1/3 ͒O 3 ͑PFW͒ is one of the classical RFE materials which can be easily obtained at lower sintering temperature and the dielectric loss is high due to the p type electron holes. 6,[24][25][26][27][28] In addition, the Curie temperature is too low ͑about −90°C͒ for practical applications.…”

Magnetic and dielectric proprieties of multiferroic (1-x)Pb(Fe2/3W1/3)O3 -XPbTiO3 Ceramics prepared via a modified two-stage solid-state reaction

“…Due to the low temperature sinterability, high permittivity and diffuse phase transition among other characteristics, lead-based complex perovskite compound have been investigated widely and have found many applications as multilayer ceramic capacitors (MLCC's), electrostrictive actuators, pyroelectric detectors, etc [1][2][3][4] . In particular, lead iron tungstate (PFW) has been studied when the interest is in dielectrics for capacitors due to its high relative permittivity, relaxor proprieties and low sintering temperatures (below 900 °C) and as well as presenting conditions for the coexistence of ferroelectric and magnetic order (multiferroic), due to two kinds of cations (Fe 3+ and W 6+ ) randomly distribute at the octahedral B-site positions 1,5,6 .…”

Electric Properties of SrTiO3Modified (Na0.48K0.48Li0.04)Nb0.89Ta0.05Sb0.06O3Lead-Free Ceramics

“…Many reports have noted that the diffused phase-transition characteristics of relaxor ferroelectric materials are related to the ordering degree of the cations. 18,[31][32][33][34][35] The diffused phase-transition property for relaxors was introduced by Smolensky with the heterogeneous composition in the micro-region. [35][36][37] Moreover, as the grain size decreases, the relaxation behavior enhances, due to domain refinement and weakening of the long-range ferroelectric property.…”