Dielectric Properties of La(Mg_0.5Sn_0.5)O₃Ceramics Doped with V₂O₅at Microwave Frequencies

Abstract

In this study, the microwave dielectric properties of V 2 O 5 -doped La (Mg 0.5 Sn 0.5 )O 3 ceramics have been investigated for application in microwave devices. La(Mg 0.5 Sn 0.5 )O 3 ceramics were synthesized by conventional mixed-oxide method and V 2 O 5 was selected as a liquid sintering aid to lower the sintering temperature of La(Mg 0.5 Sn 0.5 )O 3 ceramics. It was found that the X-ray diffraction patterns of the La(Mg 0.5 Sn 0.5 )O 3 ceramics exhibited no significant phase difference with addition levels below 2.5 wt% at different sintering temperatures. The maximum values of the dielectric constant and the quality factor multiples resonant frequency can be obtained when the La(Mg 0.5 Sn 0.5 )O 3 with 0.5 wt% V 2 O 5 additive were sintered at 1500 • C for 4h. The temperature coefficient of resonant frequency (−87.5 ppm/ • C) was measured for La(Mg 0.5 Sn 0.5 )O 3 ceramics with 0.5 wt% V 2 O 5 sintered at 1500 • C for 4 h.

Low-temperature sintering and electrical properties of strontium- and magnesium-doped lanthanum gallate with V2O5 additive

“…V 2 O 5 is known to form an intergranular liquid phase at relatively low temperature and to promote densification via liquid phase sintering [37][38][39][40]. This is consistent with the present results, namely, that the density and phase purity are increased by increasing VO 5/2 doping concentration (Figs.…”

Enhancement microwave dielectric properties of La(Mg0.5Sn0.5)O3 ceramics by substituting Mg2+ with Ni2+

“…According to the quantitative analysis, as shown in Table 2, the A grain is La 2 Sn 2 O 7 and the B and C grains are La(Mg 0.4 Ni 0.1 Sn 0.5 )O 3 . 3 . The apparent density of La(Mg 0.5−x Ni x Sn 0.5 )O 3 ceramics that were sintered at 1450-1600 • C for 4 h was highest when sintering was carried out at 1550 • C, beyond which temperature, it decreased.…”

Substituting La3+ with Sr2+ to improve microwave dielectric properties of La(Mg0.5Sn0.5)O3 ceramics

“…The dielectric constant of La(Mg 0.5 Ti 0.5−x Sn x )O 3 perovskite ceramics was found to gradually decrease from 28.4 to 19.7 with an increase in tin concentration, whereas the temperature coefficient of resonant frequency decreased from −68 to −84 ppm/ • C [11]. A dielectric constant of 15.6 and a Q × f of 30,600 GHz were obtained for La(Mg 0.5 Sn 0.5 )O 3 ceramics that were sintered at 1500 • C for 4 h [12] [15]. The fact that the ionic radius of Ba 2+ ions (0.135 nm) is larger than that of La 3+ ions (0.103 nm), motivates this study of the effect of the substitution of La 3+ by Sr 2+ to form La (1−2x/3) Sr x (Mg 0.5 Sn 0.5 )O 3 ceramics.…”