Mechanochemically enabled metastable niobium tungsten oxides

Metastable compounds have greatly expanded the synthesizable compositions of solid-state materials and have attracted enormous amounts of attention in recent years. Especially, mechanochemically enabled metastable materials synthesis has been very successful in realizing cation-disordered materials with highly simple crystal structures, such as rock salts. Application of the same strategy for other structural types, especially for non-close-packed structures, is peculiarly underexplored. Niobium tungsten oxides (NbWOs), a class of materials that have been under the spotlight because of their diverse structural varieties and promising electrochemical and thermoelectric properties, are ideally suited to fill such a knowledge gap. In this work, we develop a new series of metastable NbWOs and realize one with a fully cation-disordered structure. Furthermore, we find that metastable NbWOs transform to a cation-disordered cubic structure when applied as a Li-ion battery anode, highlighting an intriguing non-close-packed-close-packed conversion process, as evidenced in various physicochemical characterizations, in terms of diffraction, electronic, and vibrational structures. Finally, by comparing the cation-disordered NbWO with other trending cation-disordered oxides, we raise a few key structural features for cation disorder and suggest a few possible research opportunities for this field. © 2024 American Chemical Society.

Keywords

Tungsten, Niobium, Oxides, Crystal structure, Electrochemistry, Thermoelectricity, Lithium ion batteries, Diffraction, Cations, Crystal lattices, Neoplasms

Citation

Raji-Adefila, B., Wang, Y., Ding, Y., Avdeev, M., Outka, A., Gonzales, H., Engelstad, K., Sainio, S., Nordlund, D., Kan, W. H., Zhou, S., & Chen, D. (2024). Mechanochemically enabled metastable niobium tungsten oxides. Journal of the American Chemical Society, 146(15), 10498-10507. doi:10.1021/jacs.3c14275