In this work we present systematic set of measurements carried out by muon spin rotation/relaxation (μ+SR) and neutron powder diffraction (NPD) on the solid solution NaxCa1−xCr2O4. This study investigates Na-ion dynamics in the quasi-1D (Q1D) diffusion channels created by the honeycomb-like arrangement of CrO6 octahedra, in the presence of defects introduced by Ca doping. With increasing Ca content, the size of the diffusion channels is enlarged, however, this effect does not enhance the Na ion mobility. Instead the overall diffusivity is hampered by the local defects and the Na hopping probability is lowered. The diffusion mechanism in NaxCa1−xCr2O4 was found to be interstitial and the activation energy as well as diffusion coefficient were determined for all the members of the solid solution.
@article{arxiv.2211.13164,
title = {Na-ion Dynamics in the Solid Solution Na$_{\rm x}$Ca$_{1- \rm x}$Cr$_2$O$_4$ Studied by Muon Spin Rotation and Neutron Diffraction},
author = {Elisabetta Nocerino and Ola K. Forslund and Hiroya Sakurai and Nami Matsubara and Anton Zubayer and Federico Mazza and Stephen Cottrell and Akihiro Koda and Isao Watanabe and Akinori Hoshikawa and Takashi Saito and Jun Sugiyama and Yasmine Sassa and Martin Månsson},
journal= {arXiv preprint arXiv:2211.13164},
year = {2022}
}