Origin(s) of the apparent colossal permittivity in (In_1/2Nb_1/2)_xTi_1−xO₂: clarification on the strongly induced Maxwell–Wagner polarization relaxation by DC bias

Abstract

The effects of DC bias on the dielectric and electrical properties of co-doped (In1/2Nb1/2)xTi1−xO2 (IN-T), where x = 0.05 and 0.1, and single-doped Ti0.975Nb0.025O2 ceramics are investigated.

Origins of Giant Dielectric Properties with Low Loss Tangent in Rutile (Mg1/3Ta2/3)0.01Ti0.99O2 Ceramic

“…Usually, the ε value of the undoped TiO 2 ceramic is about 250 due to a lattice vibration or ionic polarization [39]. The ε value of the Ta 5+ (or Nb 5+ ) single doped TiO 2 ceramic be extremely increased to 10 4 -10 5 in the radio frequency range, while the tanδ value can also be significantly increased [14,16,40]. The simultaneously increased ε and tanδ values can be explained by electron hopping [14][15][16]24,41].…”

“…Nevertheless, the substitution of Ta 5+ (or Nb 5+ ) doped TiO 2 with acceptor dopants (e.g., Ag + , Zn 2+ , or In 3+ ) can cause a significant decrease in the tanδ value [14,16,20,23,40]. The reduced tanδ value has been explained by many factors such as defect clusters [14], insulating grain boundaries [20,42], and insulative outer surface layers [16,28,29,43].…”

Influence of Zr dopant on polarization in rutile (In0.5Nb0.5)0.005(Ti1‐xZrx)0.995O2 ceramics

“…As listed in Table , excellent dielectric properties with εʹ > 10 3 and tan δ < 0.05) were obtained over a broad temperature and frequency range. The high tan δ obtained at low frequencies range (<100 Hz at RT) or at high temperatures (>400 K at 1 kHz) is due to strong Maxwell‐Wagner effects or large leakage current during the test . At low temperature (10‐100 K), the ε ʹ value dramatically increased from 10 2 to 10 3 and was accompanied by a strong dielectric loss relaxation peak in the dielectric‐temperature spectrum.…”

“…The high tanδ obtained at low frequencies range (<100 Hz at RT) or at high temperatures (>400 K at 1 kHz) is due to strong Maxwell-Wagner effects or large leakage current during the test. 41,42 At low temperature (10-100 K), the εʹ value dramatically increased from 10 2 to 10 3 and was accompanied by a strong dielectric loss relaxation peak in the dielectric-temperature spectrum. The temperature-dependence of εʹ and εʹʹ at different fixed frequencies (ie 100 Hz, 1 kHz, 10 kHz and 100 kHz) in 15-75 K are presented in Figure 5.…”

Low‐temperature Maxwell‐Wagner relaxation in (Na + Nb) co‐doped rutile TiO2 colossal permittivity ceramics

“…With the discovery of superior colossal permittivity (CP) behavior in (Nb + In) co‐doped TiO 2 (NITO), a current burst of research activities on dual doping of TiO 2 ceramics have been stimulated. After a wealth of experimental investigations, several mechanisms, such as electron‐pinned defect‐dipole, surface barrier layer capacitor model, internal barrier layer capacitor model, surface layer effect, electron polarization, and non‐Ohmic sample‐electrode contact, had been proposed to account for this behavior. Hence, there is an ongoing debate regarding the exact origin for the CP behavior in the co‐doped TiO 2 system.…”