Journal article

Publication year: 2014

Pages: 48-58

Journal: Solid State Ionics

Volume number: 254

ISSN: 0167-2738

DOI Link: https://doi.org/10.1016/j.ssi.2013.10.042

Publisher: Elsevier

Abstract: 
The crystal structure of Cl-mayenite (Ca₁₂Al₁₄O₃₂Cl₂) is very similar to that of the well-known oxygen ion conductor O-mayenite (Ca₁₂Al₁₄O₃₃),
showing zeolite-type cages with partial occupancy by oxygen anions. In
Cl-mayenite chlorine ions occupy the cage centers instead of oxygen
ions, and it is of interest whether these chlorine ions are mobile and
whether Cl-mayenite is a chlorine ion conductor. The answer for these
questions is the focus of the paper. High temperature neutron powder
experiments and impedance spectroscopy measurements were performed. For
information on possible chloride migration pathways and activation
energies, quantum-chemical calculations based on density-functional
theory were carried out. The behavior of Cl⁻ is in clear contrast to O^2 −
in O-mayenite: even at high temperatures it only shows normal harmonic
thermal displacement without indications for long range diffusion
between the cages. The total ionic conductivity was found to be very low
with a value of σ ≈ 10^− 6 S cm^− 1 at 1073 K. Quantum-chemical calculations result in a very high activation barrier for Cl⁻ migration of 3.07 eV.

Harvard Citation style: Schmidt, A., Lerch, M., Eufinger, J., Janek, J., Tranca, I., Islam, M., et al. (2014) Chlorine ion mobility in Cl-mayenite (Ca12Al14O32Cl2): An investigation combining high-temperature neutron powder diffraction, impedance spectroscopy and quantum-chemical calculations, Solid State Ionics, 254, pp. 48-58. https://doi.org/10.1016/j.ssi.2013.10.042

APA Citation style: Schmidt, A., Lerch, M., Eufinger, J., Janek, J., Tranca, I., Islam, M., Bredow, T., Dolle, R., Wiemhöfer, H., Boysen, H., & Hölzel, M. (2014). Chlorine ion mobility in Cl-mayenite (Ca12Al14O32Cl2): An investigation combining high-temperature neutron powder diffraction, impedance spectroscopy and quantum-chemical calculations. Solid State Ionics. 254, 48-58. https://doi.org/10.1016/j.ssi.2013.10.042