Dielectric Properties of Bismuth Niobate Ceramics

Abstract

The development of new dielectric materials that allow the reduction of size and weight of electronic components has been in the scope of the researchers. The bismuth-based dielectric ceramics are extensively studied for this purpose, namely, the bismuth niobate (BiNbO 4). The first attempt to improve BiNbO 4 occurred in 1992 when Kagata reported the microwave dielectric properties of bismuth niobate doped with the addition of oxides. This chapter will present a brief review of the several attempts that have been carried out to enhance the dielectric properties of BiNbO 4 by modifying their structure through addition, doping, or atom(s) substitution. This manuscript focuses on a case study that involves bismuth substitution by europium ions. To investigate the inclusion of europium in BiNbO 4 ceramics, (Bi 1-x Eu x)NbO 4 samples were prepared using the sol-gel method, in particular, the citrate route. The structure of the prepared samples was studied by X-ray diffraction (XRD) and Raman spectroscopy and the morphology by scanning electron microscopy (SEM). The dielectric properties were studied, in the microwave frequency range (MW), using the resonant cavity method, and in the radio frequency range (RF), with the impedance spectroscopy technique.

Structural, Morphological and Dielectric Characterization of BiFeO3 Fibers Grown by the LFZ Technique

“…This analysis was made in the temperature range of 100 and 380 K, using a nitrogen bath cryostat setup. During the measurements, the samples were kept in a helium atmosphere to avoid moisture and minimize thermal gradients [13][14][15]. The measurements were made with a Network Analyzer, Agilent 4294, operating between 100 Hz and 1 MHz in the C p -R p configuration (capacitance in parallel with resistance).…”