Near Constant Loss Dielectric Response in 2Bi₂O₃–B₂O₃ Glasses

Abstract

Electrical conduction and relaxation phenomena in bismuth borate glasses in the composition 2Bi2O3–B2O3 (Bi4B2O9) were investigated. Dielectric studies carried out on these glasses revealed near constant loss response in the 1 kHz–1 MHz frequency range at moderately high temperatures (300–450 K) associated with relatively low loss (tan δ = 0.006) and high dielectric constant (εr′ = 37) at 1 kHz, 300 K. The variation in AC conductivity with temperature at different frequencies showed a cross over from near constant loss response characterized by local ion vibration within the potential well to universal Jonscher's power law dependence triggered by ion hopping between potential wells or cages. Thermal activation energy for single potential well was found to be 0.48 ± 0.05 eV from cross over points. Ionic conduction and relaxation processes were rationalized by modulus formalism. The promising dielectric properties (relatively high εr′ and low tan δ) of the present glasses were attributed to high density (93% of its crystalline counterpart), high polarizability, and low mobility associated with heavy metal cations, Bi3+.

Characterization of zinc lead-borate glasses doped with Fe3+ ions: optical, dielectric, and ac-conductivity investigations

“…Broadband dielectric spectroscopy (BDS) became recently one of the main fruitful techniques for probing dynamic processes and the different mechanisms of the electrical conductivity in advanced glasses and glass ceramics owing to its extensive range of frequency and temperatures [10][11][12][13][14]. There are many studies focused recently on the effect of structure, temperature, and frequency on the electrical properties of conductive glasses [11,[14][15][16][17][18][19][20]. The electrical conductivity plays the main role of the variations in all dielectric values (such as permittivity, dielectric loss, electric modulus,…etc.)…”

Compositional dependence of properties in calcium substituted sodium borophosphate glasses containing $${\hbox {VO}}^{2+}$$ VO 2 + ions

“…In order to eliminate the electrode polarization effect, an alternative approach called electric modulus analysis is used to investigate the complex electrical response of glassy materials [65]. The complex electric modulus (M * ) can be calculated using the formula [66]: Figures 8 and 9 show the variation of the real (M ) and imaginary (M ) parts of the electrical modulus at different temperatures for the CNV3 sample respectively. At higher frequencies, M reaches a maximum while at lower frequencies it approaches zero indicating a negligible contribution due to electrode polarization [65].…”

The conduction mechanism and dielectric behavior of cadmium bismuth silicate glasses

“…The inclusion of different heavy metal oxides, such as Bi2O3, PbO were reported to improve the physical properties of silicate glasses. The strong polarizability of bismuth ion and 6s 2 electronic lone-pair in the valence shell of Bi2O3, may significantly alter the electrical characteristics of the oxide glasses [10,11]. Thus, in view point of above present work if focused to study the effect of introduction of SiO2 (traditional glass former) at the expense of Bi2O3 (conditional glass former) at a constant CdO concentration on the electrical properties of binary cadmium bismuthate glass.…”