Structure and magnetodielectric properties of titanium substituted barium hexaferrites

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10439268" target="_blank" >RIV/00216208:11320/21:10439268 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=b16PWBFRUw" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=b16PWBFRUw</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ceramint.2021.03.041" target="_blank" >10.1016/j.ceramint.2021.03.041</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Structure and magnetodielectric properties of titanium substituted barium hexaferrites

Popis výsledku v původním jazyce

BaFe12-xTixO19 barium hexaferrites up to x = 2.00 were synthesized by the usual ceramic technology. Crystal structure refinement was realized by Rietveld method of powder XRD at room temperature. The unit cell parameters change non-monotonically with titanium concentration. The minimum volume of -698.75 angstrom 3 was determined for the x = 1.00. The mechanism of nonequivalent crystallographic positions occupation with titanium cations is established. SEM investigation was shown that the obtained samples are ceramics with a tightly compacted polycrystals (&gt;95%) and average crystallite size of -5 mu m. The Mo center dot ssbauer investigation confirms such localization of Ti4+ cations. The field dependence of magnetization at 5 K and 300 K was measured and the main magnetic parameters were determined using the law of approach to saturation. These values decrease almost monotonically with increase in titanium concentration and temperature. The minimum values of these quantities of -23.4 emu/g, -1.9 emu/g, 1.2*106 Erg/g and -105 Oe were fixed for the x = 2.00 at 300 K. With an increase in the doping concentration, both the magnitude of the electrical ac-resistivity and the temperature of transition to the activation type of conductivity increase non-monotonically. At x = 0.50, the lowest electrical resistivity of rho -5.1*103 Ohm*cm is observed at room temperature with the electrical transition temperature is Tel -406.5 K. With an increase in frequency the ac-resistivity decreases, as the value of the band gap. The real part of the permittivity increases constantly with increasing temperature and decreases with increasing frequency for all the compositions. The temperature peak of the tg(d) loss tangent with the doping concentration changes nonmonotonically in magnitude and position. An interpretation of the magnetic and electric states of the substituted BaFe12-xTixO19 barium hexaferrite is given taking into account the mechanism of occupation nonequivalent crystallographic positions with titanium cations.

Název v anglickém jazyce

Structure and magnetodielectric properties of titanium substituted barium hexaferrites

Popis výsledku anglicky

BaFe12-xTixO19 barium hexaferrites up to x = 2.00 were synthesized by the usual ceramic technology. Crystal structure refinement was realized by Rietveld method of powder XRD at room temperature. The unit cell parameters change non-monotonically with titanium concentration. The minimum volume of -698.75 angstrom 3 was determined for the x = 1.00. The mechanism of nonequivalent crystallographic positions occupation with titanium cations is established. SEM investigation was shown that the obtained samples are ceramics with a tightly compacted polycrystals (&gt;95%) and average crystallite size of -5 mu m. The Mo center dot ssbauer investigation confirms such localization of Ti4+ cations. The field dependence of magnetization at 5 K and 300 K was measured and the main magnetic parameters were determined using the law of approach to saturation. These values decrease almost monotonically with increase in titanium concentration and temperature. The minimum values of these quantities of -23.4 emu/g, -1.9 emu/g, 1.2*106 Erg/g and -105 Oe were fixed for the x = 2.00 at 300 K. With an increase in the doping concentration, both the magnitude of the electrical ac-resistivity and the temperature of transition to the activation type of conductivity increase non-monotonically. At x = 0.50, the lowest electrical resistivity of rho -5.1*103 Ohm*cm is observed at room temperature with the electrical transition temperature is Tel -406.5 K. With an increase in frequency the ac-resistivity decreases, as the value of the band gap. The real part of the permittivity increases constantly with increasing temperature and decreases with increasing frequency for all the compositions. The temperature peak of the tg(d) loss tangent with the doping concentration changes nonmonotonically in magnitude and position. An interpretation of the magnetic and electric states of the substituted BaFe12-xTixO19 barium hexaferrite is given taking into account the mechanism of occupation nonequivalent crystallographic positions with titanium cations.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Ceramics International

ISSN

0272-8842

e-ISSN

—

Svazek periodika

47

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

14

Strana od-do

17293-17306

Kód UT WoS článku

000648619700005

EID výsledku v databázi Scopus

2-s2.0-85102432845