Predominant Factor of Activation Energy for Ionic Conductivity in Perovskite-Type Lithium Ion-Conducting Oxides

Abstract

The predominant factors of the activation energy for ionic conductivity in perovskite-type lithium ion-conducting oxides were discussed in terms of structural distortion. As the result, the activation energies in almost all compounds are governed by a factor, a p /(B large -O) (a p : perovskite parameter (cube root of cell volume per formula unit), (B large -O) : inter-atomic distance between larger B ion and oxygen ion). This finding implies that (i) the larger B ion gives rise to structural distortion such as the tilt of the BO 6 octahedra, which decrease the bottleneck size, (ii) the resultant smaller bottleneck determines the activation energies for ionic diffusion.

High-throughput screening of chalcogenide single perovskites by first-principles calculations for photovoltaics

“…These computational errors may be ascribed to (i) the used exchange-correlation functional, as reported by Han et al [21], who found that the PBE underestimates the stability of some of the halide perovskites; (ii) at finite temper ature in experiments, entropy contributions to free energies are not included in DFT calculations; (iii) dynamic stabilities are not considered in formation energy calculations. In comparison to the results of 31 types of existing perovskites in experiments [19, [22][23][24][25][26][27][28][29][30][31], we have found that 60 meV/atom is a proper border line in formation energies for separating stable and unstable perovskites, as shown in figure 4. Current thermodynamic stability calculations are performed on ground-state level by DFT calculations at 0 K. Previous calcul ations of hybrid halide perovskites at 300 K [32] showed that the entropies could contribute more for products (by 0-50 meV/atom) than that for reactants, thus stabilizing perovskite phases.…”

Relationship between activation energy for hydrogen permeation and hydrogen permeation properties of amorphous Cu50Zr50 and Cu65Zr35 membranes

“…Various activation energy parameters affect the properties of materials, such as the activation energies for ionic conductivity [1], surface self-diffusion [2], creep [3], oxidation [4], structural relaxation [5], crystallization [6], and permeation [7]. In particular, in hydrogen-separable membranes, the activation energy for hydrogen permeation is a crucial parameter affecting the hydrogen permeability [8,9].…”

Lithium-Ion Diffusion in Perovskite-Type Solid Electrolyte Lithium Lanthanum Titanate Revealed by Pulsed-Field Gradient Nuclear Magnetic Resonance

“…4 Moreover, Inaguma et al demonstrated that the decrease in the tilt angle due to ion substitution lowers the activation energy. 90 The two activation energies obtained by PFG-NMR analysis and the change in C Q observed in the static NMR spectra both support the change in the local environment with the change in the TiO 6 tilt angle. On the other hand, the cause of non-Arrhenius behavior remains under debate.…”

“…Varez et al emphasized the relationship between the tilt angle of TiO 6 octahedra and the change in activation energy. , The rotational motion of TiO 6 promotes hopping of the Li + ions, and thus, the smaller the tilt angle, the lower the activation energy . Moreover, Inaguma et al demonstrated that the decrease in the tilt angle due to ion substitution lowers the activation energy . The two activation energies obtained by PFG-NMR analysis and the change in C Q observed in the static NMR spectra both support the change in the local environment with the change in the TiO 6 tilt angle.…”