Electrical conductivity and relaxation phenomena in Li2O·B2O3 based glass and glass-ceramic: A comprehensive and comparative analysis. (November 2022)

• Record Type: Journal Article
• Authors: Kumar, Sachin; Kumari, Suman; Kumar, Vibhor; Dalal, Jasvir; Kumar, Anand; Ohlan, Anil
• Is Part Of: Journal of physics and chemistry of solids. Volume 170(2022)
• Publication Date: 2022-11
• Subjects: Glass -- Glass-ceramics -- Electrical conductivity -- Relaxation mechanism -- Impedance spectroscopy; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2022.110911
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: This work reports a detailed investigation on the electrical conductivity and dielectric relaxation phenomena in Li2 O·B2 O3 based glass and glass-ceramic materials. Measurements reveal that the electrical conductivity of glass-ceramic is lower than glass. This owes to occurrence of grain boundaries which impede the mobility of charge carriers in glass-ceramic as confirmed by FESEM micrographs. The frequency-dependent behavior of electrical conductivity, within the measured temperature range, is analysed using Jonscher's power law. It is found that the conductivity rises with an increase in temperature and the range of conductivity reveals the semiconducting behavior of the material. The ac conductivity mechanism of system is observed to follow the overlapping large polaron tunneling model. The conduction and relaxation mechanism studies are performed using electric modulus and impedance spectroscopy within the frequency and temperature ranges varied from 10 3 Hz to 10 7 Hz and 593 K–773 K, respectively. Analysis of the relaxation mechanism in both samples is performed employing Kohlrausch-William-Watts (KWW) model, which reveals that the charge carriers are following non-Debye type relaxation. To distinguish between the contribution of grain boundaries and grains in the relaxation mechanism, a combined analysis of complex electric module and impedance spectroscopy has been discussed. Highlights: 20Li2 O·80B2 O3 based glass and glass-ceramic has been studied at higher temperature. FTIR analysis reveals that both samples possess analogous structural units. Non ideal - Debye type relaxation is observed in the studied glass and glass-ceramic system. Conduction mechanism is contributed by both long-range and short-range movement of charge carriers. The variations of frequency exponent reveal the applicability of OLPT model for conduction mechanism.