Gel Synthesis of Hexaferrites Pb1-xLaxFe12-xZnxO19 and Properties of Multiferroic Composite Ceramics PZT-Pb1-xLaxFe12-xZnxO19.

ABSTRACT: We investigated the opportunities for obtaining hexaferrites Pb1-xLaxFe12-xZnxO19 (x = 0-1) from citrate-glycerin gel and showed that synthesis occurs via the formation of the Fe3O4 phase; products with a small amount of hematite impurity Fe2O3 can be obtained after firing at 800 to 900 °C with 0 ? x ? 0.5. If x > 0.5, perovskite-like LaFeO3 is formed in samples, so that if x = 0.9-1, the synthesis products virtually do not contain phases with hexaferrite structures and represent a mixture of LaFeO3, Fe2O3, and Fe3O4. Within the range of 0 ? x ? 0.5, the electrical and magnetic characteristics of hexaferrites Pb1-xLaxFe12-xZnxO19 are slightly dependent on x and have the following average values: A relative permittivity ?/?0 ~ 45, a dielectric loss tangent tan ? ~ 0.6, an electrical resistivity R ~ 109 Ohm cm, coercivity Hc ~ 3 kOe, saturation magnetization Ms ~ 50 emu/g, and remanent magnetization Mr ~ 25 emu/g. The magnetoelectric (ME) ceramics 50 wt.% PZTNB-1 + 50 wt.% Pb1-xLaxFe12-xZnxO19 (PZTNB-1 is an industrial piezoelectric material based on lead titanate zirconate (PZT) do not contain impurity phases and have the following characteristics: Piezoelectric coefficients d33 = 10-60 and -d31 = 2-30 pC/N, piezoelectric voltage coefficients g33 = 2-13 and -g31 = 1-5 mV m/N, an electromechanical coupling coefficient Kp = 0.03-0.13, magnetic parameters Hc = 3-1 kOe, Ms = 50-30, and Mr = 25-12 emu/g. The maximum ME coupling coefficient ?E/?H ~ 1.75 mV/(cm Oe) was achieved with x = 0.5.

SUBMITTER: Lisnevskaya IV 

PROVIDER: S-EPMC7559289 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature