Maxwell–Wagner relaxation in CaCu3Ti4O12/Ag composites

Study of the interfacial MWS relaxation by dielectric spectroscopy in unidirectional PZT fibres/epoxy resin composites

“…The mean relaxation time being very close to the characteristic time of Debye (10 −13 s); it appears that the MWS effect is a thermo-activated phenomenon related to elementary relaxations of dipoles. Other studies have also revealed similar results in different heterogeneous systems [30,31].…”

Fabrication and dielectric properties of Ba(Fe0.5Nb0.5)O3/poly(vinylidene fluoride) composites

“…The activation energy is close to that of 0.53 eV for CCTO/Ag composites [21], implying that the BFN/PVDF composites have common physics with that in CCTO/Ag composites. It is associated with an inhomogeneous dielectric medium containing two or more materials with different permittivity and conductivity [21]. A charge carrier concentration discontinuity across the interface would be happened at external electric field [21].…”

“…The parameter of activation energy of BFN/PVDF composite with 40 vol% BFN deduced from the linear fit are found to be 0.583 eV. The activation energy is close to that of 0.53 eV for CCTO/Ag composites [21], implying that the BFN/PVDF composites have common physics with that in CCTO/Ag composites. It is associated with an inhomogeneous dielectric medium containing two or more materials with different permittivity and conductivity [21].…”

“…It is associated with an inhomogeneous dielectric medium containing two or more materials with different permittivity and conductivity [21]. A charge carrier concentration discontinuity across the interface would be happened at external electric field [21]. Therefore, interfacial polarization could be easily realized.…”

Low-temperature dielectric properties of double-perovskite Ca2CoNbO6

“…The first feature might be because that the concentration of the oxygen vacancy is very sensitive to the sample preparation process and sample geometry as reported in CaCu 3 Ti 4 O 12 [32]. The reduction of sample thickness leads to the great decrease in the number of defect dipole, since the Co deficient easily occurs at the out most part of the sample as reported in other volatile element, like Ag in CaCu 3 Ti 4 O 12 [33]. The ionization of oxygen vacancies creates negatively charged electrons, while the cobalt vacancies produce positively charged holes.…”