Investigation of resistive, capacitive and conductive properties of lead-free electronic material: 0.7Bi(Fe0.98Ga0.02)O3-0.30BaTiO3

NiO–Ti nanocomposites for contact electrification and energy harvesting: experimental and DFT+U studies

“…In the lower frequency region, the dielectric permittivity depicted a higher value than in the higher frequency region due to the various polarizations, such as dipolar, space charge, and interfacial. 36 The dielectric permittivity decreased significantly as the frequency increased from 100 Hz to 1 MHz because dipoles cannot reorient or rotate themselves in the presence of fast varying electric fields, leading to them making no contribution toward polarization or ion accumulation. Hence a decrease in dielectric permittivity was observed at higher frequency, which could be expressed by the Maxwell–Wagner theory.…”

Rational Sol–Gel-Based Synthesis Design and Magnetic, Dielectric, and Optical Properties Study of Nanocrystalline Sr3Co2WO9 Triple Perovskite

“…The frequency-dependent AC conductivity expresses the hopping dynamics of ions. Dielectric data are utilized for the ac conductivity calculation using the relation: σ ac = ωεε 0 tan δ, where ε 0 = dielectric permittivity of free space (ε 0 = 8.854 × 10 –12 F m –1 ) and the other parameters have their usual meanings Figure depicts the frequency dependence of σ ac at selected temperatures along with fitting related to Jonscher’s power law: σ ac (ω) = A ω n where “ A ” is the strength of polarizability and “ n ” is the dimensionless frequency exponent representing the interaction between mobile ions in the lattice.…”

“…Dielectric data are utilized for the ac conductivity calculation using the relation: σ ac = ωεε 0 tan δ, where ε 0 = dielectric permittivity of free space (ε 0 = 8.854 × 10 −12 F m −1 ) and the other parameters have their usual meanings. 53 Figure 13 depicts the frequency dependence of σ ac at selected temperatures along with fitting related to Jonscher's power law: σ ac (ω) = Aω n where "A" is the strength of polarizability and "n" is the dimensionless frequency exponent representing the interaction between mobile ions in the lattice. The small value of n (<1) suggests involving a translational motion with a sudden hopping, whereas a larger value of n (>1) suggests involvement of localized hopping without the species leaving the neighborhood.…”

A Review of a Good Binary Ferroelectric Ceramic: BaTiO3–BiFeO3

“…Impedance spectroscopy could differentiate the contribution of the grain and grain boundary to the resistance. 96 The change of resistance with temperature will reflect the material's positive temperature coefficient resistance or negative temperature coefficient resistance behavior. The change of resistance must arouse the change of leakage current.…”

“…The nonstoichiometric ratio and valence fluctuation of Fe ion also contribute to the leakage current. ,,− These problems restricted the application of it. Many attempts, the partial substitution (such as La, Nb, Mn) and the formation of solid solutions with other materials (such as BTO, PbTiO 3 ), have been made to solve this problem. ,, Some impurities often appeared in the product of annealing. The BiFeO 3 decomposed to Bi 2 Fe 4 O 9 and Bi 25 FeO 39 in the temperature interval 447–767 °C; this is because Bi-rich and Fe-rich phases are more thermodynamically stable than BFO at this temperature range .…”