Giant permittivity and good thermal stability of LiCuNb₃O₉-Bi(Mg0.5Zr0.5)O₃solid solutions

Abstract

(1 À x)LiCuNb 3 O 9 -xBi(Mg 0:5 Zr 0:5 )O 3 ceramics ((1 À x)LCN-xBMZ) with 0 x 0:08 were synthesized by a solid-state reaction method. The phase structure of (1 À x)LCN-xBMZ ceramics was characterized by X-ray diffraction (XRD), which revealed that the ceramics were distorted cubic perovskite structures. Apparent giant permittivity of 1:98 Â 10 4 -1:05 Â 10 5 at 100 kHz over the measured temperature range (25 C-250 C) was observed in the sintered (1 À x)LCN-xBMZ (0 x 0:08) ceramics. Especially for the sample of x ¼0.04, the temperature stability of permittivity was markedly increased (Á"/" 100 C AE15%), and high relative permittivity (> 8:3 Â 10 4 ) were obtained over a wide temperature range from 100 C to 250 C at 100 kHz, which indicates that this ceramic is a promising dielectric material for elevated temperature dielectrics. The giant dielectric property of (1 À x)LCN-xBMZ ceramics are profoundly concerned with the Maxwell-Wagner effect.

Lead-Free BiFeO3–BaTiO3 Ceramics: An Overview

“…The improvement in ferroelectricity of BFO-BTO ceramic system is done through substitution of different ions, for example Co 3+ , Cu 2+ , Mn 2+ , La 2+ , Nd 3+ , Dy 3+ , Er 3+ , Eu 3+ , Cr 3+ , Ni 2+ , Al 3+ , Ce 2+ , Gd 3+ , and Ga 3+ [44][45][46][47][48][49][50][51][52][53]. The electrical properties are also improved in multiphase solution like BiMeO 3 (Me = Al, Ga, Y, Sc, Zn 1/2 Ti 1/2 , Mg 2/3 Nb 1/3 , Zn 2/3 Nb 1/3 ), La 0.7 Sr 0.3 MnO, Na 0.5 Bi 0.5 TiO 3 [32,[54][55][56][57][58].…”

A Review of a Good Binary Ferroelectric Ceramic: BaTiO3–BiFeO3

“…Many researchers studied the monodoped in BTO–BFO ceramics, such as Eu 3+ , Co 3+ , Cr 3+ , Cu 2+ , Ni 2+ , Mn 2+ , Al 3+ , La 2+ , Ce 2+ , Nd 3+ , Gd 3+ , Dy 3+ , Ga 3+ , and Er 3+ . ,− The doping of these ions could improve the ferroelectricity of BTO–BFO ceramics. The multiphase solid-state solution could also promote the electrical properties of BTO–BFO ceramics, like La 0.7 Sr 0.3 MnO 3 , Na 0.5 Bi 0.5 TiO 3 , BiMeO 3 (Me = Al, Ga, Sc, Y, Mg 2/3 Nb 1/3 , Zn 2/3 Nb 1/3 , Zn 1/2 Ti 1/2 ), CaSnO 3 , etc. ,− …”

“…BTO–BFO ceramics with pseudocubic or a combination of pseudocubic and rhombohedral phases are less thermally stable than those with rhombohedral phases . Doping or substitution, such as Al, Na, Bi 0.5 Na 0.5 TiO 3 , La­(Mg 0.5 Ti 0.5 )­O 3 , and MnO 2 –CuO, could increase the temperature stability or insulating properties of BTO–BFO. ,,− The universal core–shell microstructures in this system could also increase thermostability . The addition of Na could enhance the Curie temperature of BTO–BFO …”