These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
Role of Interlayer Distance on Cationic Diffusion of Nickel-Based Honeycomb Layered Tellurates
preprintsubmitted on 06.01.2021, 00:00 and posted on 06.01.2021, 13:08 by Kartik Sau, Tamio Ikeshoji, Godwill Mbiti Kanyolo, Titus Masese
Although the fascinatingly rich crystal chemistry of honeycomb layered oxides has been accredited as the propelling force behind their remarkable electrochemistry, the atomistic mechanisms surrounding their operations remain unexplored. Thus, herein, we present an extensive molecular dynamics study performed systematically using a refined set of inter-atomic potential parameters of A2Ni2TeO6 (where A = Li, Na, and K). We demonstrate the effectiveness of the Vashishta-Rahman form of the interatomic potential in reproducing various structural and transport properties of this promising class of materials and predict an exponential increase in cationic diffusion with larger interlayer distances. The simulations further demonstrate the correlation between broadened inter-layer (inter-slab) distances associated with the larger ionic radii of K and Na compared to Li and the enhanced cationic conduction exhibited in K2Ni2TeO6 and Na2Ni2TeO6 relative to Li2Ni2TeO6. Whence, our findings connect a wider bottleneck along the cationic diffusion channel within frameworks comprised of larger mobile cations to the improved cationic diffusion experimentally observed in honeycomb layered oxides.