Effect of intergranular glass films on the electrical conductivity of 3Y-TZP

Abstract

The electrical conductivity of 3Y-TZP ceramics containing SiO2 and AI2O3 has been investigated by complex impedance spectroscopy between 500 and 1270 K. At low temperatures, the total electrical conductivity is suppressed by the grain boundary glass films. The equilibrium thickness of intergranular films is 1-2 nm, as derived using the "brick-layer" model and measured by HRTEM. A change in the slope of the conductivity Arrhenius plots occurs at the characteristic temperature Tb at which the macroscopic grain boundary resistivity has the same value as the resistivity of the grains. The temperature dependence of the conductivity is discussed in terms of a series combination of RC elements.

Synthesis and characterization of Li1/3Ce2/3PO4and LiCe2/3PO4ceramics

“…The high-frequency part of the obtained spectra may be attributed to the relaxation in grain boundaries, while the lower-frequency part corresponds to processes related to interfaces between the Pt electrodes and the superionic material. The dispersion related to ionic processes in grains is usually observed at high frequencies and temperatures up to about 500 K [12,[24][25][26]. In our case this dispersion region was not measured due to the low ionic conductivity of the investigated ceramics.…”

“…Different sintering time of the ion conductive ceramics mainly affects the amount of grain boundaries due to grain growth and consequently their contribution to the electrical conductivity [12,24,25,27]. The results of the measurements of electrical parameters at 600 K for Li 1/3 Ce 2/3 PO 4 and LiCe 2/3 PO 4 ceramics sintered for different t s are presented in table 6.…”

Synthesis, structure, and electric properties of Li1+xScxZr2-x(PO4)3(x= 0.1, 0.2, 0.3) ceramics

“…Two dispersion regions were found in σ spectra for all the investigated samples. The high frequency part of the obtained spectra may be attributed to the relaxation in grains, while the lower frequency part corresponds to the grain boundary processes, like in the wide range of other solid electrolyte ceramics [18][19][20][21].…”

X-ray photoelectron and broadband impedance spectroscopy of Li_1+4<i>x</i>Ti_2-<i>x</i>(PO₄)₃ solid electrolyte ceramics

“…Two dispersion regions in σ' spectra for all investigated compounds were found. The low frequency dispersion range of σ' is caused by ion transport in grain boundary because high frequency range is attributed to ion transport in grain as in [19][20][21][22]. The processes are thermally activated and dispersion regions shift towards higher frequencies as temperature increases.…”