The impedance, dielectric and piezoelectric properties of Tb4O7 and Tm2O3 doped KNN ceramics

Influence of Oxygen Vacancies on the Impedance Spectrum of Al2O3–Na0.5K0.5NbO3 Composites

“…For instance, Zeng et al showed that the activation energy evaluated by the temperature-dependent conductivity could be decreased by doping 0.3Pb(Zn 1/3 Nb 2/3 )O 3 -0.7Pb(Zr 0.49 Ti 0.51 )O 3 with LiF, as the number of oxygen vacancies increased [18]. Similar results were measured for Tb-and Tm-doped NKN [19]. However, the activation energy can also be changed during fatigue, as shown by Nishiyama et al [20] in Li-modified NKN.…”

“…Impedance spectroscopy is a versatile tool that can be used to characterize the electrical properties of polycrystalline microstructures [17]. In addition to the possibility of gathering information on the dielectric and conductive properties of grains, grain boundaries, and interfaces, changes in the domain structure and oxygen vacancies can be measured [18][19][20][21]. For instance, Zeng et al showed that the activation energy evaluated by the temperature-dependent conductivity could be decreased by doping 0.3Pb(Zn 1/3 Nb 2/3 )O 3 -0.7Pb(Zr 0.49 Ti 0.51 )O 3 with LiF, as the number of oxygen vacancies increased [18].…”

Enhanced electrical properties and conduction mechanism of A-site rare-earth Nd-substituted CaBi2Nb2O9

“…The synergetic effects of Li/Nd at the A-site and W/Mn at the B-site greatly enhance the piezoelectric properties (d 33 ∼ 21.1 pC N −1 ) of CBN [25]. In addition to grain-orientation techniques and multi-element composition adjustment, single rare-earth ion modification through the conventional solid-state reaction method is also an effective method to enhance both the piezoelectric performance and Curie temperature [26][27][28]. For example, it has been reported that Gd-modified CBN possesses improved piezoelectric properties with a high d 33 of 13 pC N −1 and a high T c of 947 • C [18].…”