Effect of Bi2O3–B2O3 as a sintering aid in microstructure and dielectric properties of Fe2Mo3O12 electroceramic

Molybdates from A2Mo3O12 family have been widely investigated due to its low sintering temperature, thermal expansion coefficient, and dielectric loss. Fe2Mo3O12 (FMO) is an oxide this used in the catalytic field. The aim of work evaluate influence Bi2O3–B2O3 as a aid microstructure properties FMO. diffraction results showed that FMO with monoclinic structure phase was obtained after calcination process (650 °C). Mössbauer spectroscopy formation Fe2O3 at 800 °C. scanning electron-microscopic image demonstrates increase grain function concentration. samples were analyzed using impedance radiofrequency temperature variation. Nyquist diagram range fitted equivalent circuit three R-CPE associations, corresponding morphology electroceramics. For microwave, all values εr lower than 10. Values Q x f above 14,132.35 GHz achieved. stability evaluated by coefficient resonant frequency (τf). lowest τf − 6.55 ppm/°C 4.35 (near-zero) measured mixed 7.5 wt % Bi2O3–B2O3, respectively. Based on these results, can be low-permittivity ceramic for low-temperature co-fired ceramics (LTCC) applications, antenna substrate, millimeter-wave range.