2024/01/25 by Titus Masese, Godwill Mbiti Kanyolo, Masese, Titus +13
Materials Science · #FOS: Physical sciences #Machine Learning in Materials Science #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2402.04266
openalex publication_date 2024/01/25 · openalex created_date 2024/02/09 · openalex updated_date 2026/07/28
The scarcity of viable electrode and electrolyte materials vastly hinders the advancement of magnesium and calcium batteries. This study utilises solid-state metathetical reactions involving chalcogen- and pnictogen-based honeycomb layered oxides with alkaline-earth halides/nitrates to synthesise \rm Mg2+- and \rm Ca2+-based materials previously achievable only under high-temperature/high-pressure conditions, as well as new metastable materials with unique crystal versatility. Particularly, we employ metathetical reactions involving \rm Li4MgTeO6, \rm Na2Mg2TeO6, and \rm Na4MgTeO6 with \rm MgCl2/\rm MgSO4/\rm Mg(NO3)2.\rm 6H2O or \rm Ca(NO3)2.\rm 4H2O / \rm CaCl2.\rm 2H2O at temperatures not exceeding 500 ^∘C to produce \rm Mg3TeO6 polymorphs, ilmenite-type \rm CaMg2TeO6/\rm Mg2CaTeO6, and double perovskite-type \rm Ca2MgTeO6. Thus, we demonstrate that these materials, conventionally requiring gigascale pressures or high temperatures (>1000^∘C) for their proper synthesis, are now readily accessible at ambient pressure and considerably lower temperatures. Meanwhile, despite sub-optimal pellet densities, the synthesised ilmenite-type \magenta \rm Mg3TeO6 (high-pressure polymorph) and double perovskite-type \rm Ca2M\rm TeO6 (M = \rm Mg, Ca, Zn) materials exhibit remarkable bulk ionic conductivity at room temperature, marking them as promising compositional spaces for exploring novel \rm Mg2+ and \rm Ca2+ conductors. Furthermore, this study extends the applicability of metathetical reactions to attain Mg- or Ca-based antimonates, ruthenates, titanates, phosphates, and silicates, thus opening avenues to novel high-entropy multifunctional nanomaterial platforms with utility in energy storage and beyond.