6533b823fe1ef96bd127f4af

RESEARCH PRODUCT

Dielectric relaxation phenomenon and conductivity in lead-free ceramics

Adel MegricheImen KradImen KradOlivier BidaultNissrine ZaiterMohamed El Maaoui

subject

Materials scienceCondensed matter physicschemistry.chemical_element02 engineering and technologyActivation energyDielectricConductivityAtmospheric temperature range010402 general chemistry021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesOxygen0104 chemical sciencesElectronic Optical and Magnetic MaterialschemistryElectrical resistivity and conductivityRelaxation (physics)Electrical and Electronic Engineering0210 nano-technologySolid solution

description

Abstract Relaxation phenomena and electric conductivity of (1-x) KNbO3-xK0.5Bi0.5TiO3 system where x = 0, 0.025, 0.05, 0.075, 0.1, 0.2, 0.3 have been studied at high temperature. A relaxation behavior was observed in temperature range 400 K ≤ T ≤ 550 K for orthorhombic solid solutions at room temperature. The activation energy (Ea) of this phenomenon was range from 0.68 eV for x = 0–0.489 eV for x = 0.075 with τ0 = 10−13 s. The relaxation was attributed to hopping of oxygen vacancies for solid solutions x ≤ 0.075. Substitution by K0.5Bi0.5TiO3 does not affect the electrical conductivity of KNbO3 too much, while the mobility of species such as oxygen vacancies and oxygen ions allow the increase of the conductivity σac at high temperatures.

yearjournalcountryeditionlanguage
2018-09-01Physica B: Condensed Matter
https://doi.org/10.1016/j.physb.2018.06.022