Lithium containing layered high entropy oxide structures

• Published in: Scientific reports Vol. 10; no. 1; p. 18430
• Main Authors: Wang, Junbo, Cui, Yanyan, Wang, Qingsong, Wang, Kai, Huang, Xiaohui, Stenzel, David, Sarkar, Abhishek, Azmi, Raheleh, Bergfeldt, Thomas, Bhattacharya, Subramshu S, Kruk, Robert, Hahn, Horst, Schweidler, Simon, Brezesinski, Torsten, Breitung, Ben
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 28.10.2020; Nature Publishing Group UK
• Subjects: Chromium; Copper; Energy storage; Entropy; Lithium; Manganese; Mossbauer spectroscopy; Oxides; Pyrolysis
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-75134-1

Layered Delafossite-type Li (M M M M M …M )O materials, a new class of high-entropy oxides, were synthesized by nebulized spray pyrolysis and subsequent high-temperature annealing. Various metal species (M = Ni, Co, Mn, Al, Fe, Zn, Cr, Ti, Zr, Cu) could be incorporated into this structure type, and in most cases, single-phase oxides were obtained. Delafossite structures are well known and the related materials are used in different fields of application, especially in electrochemical energy storage (e.g., LiNi Co Mn O [NCM]). The transfer of the high-entropy concept to this type of materials and the successful structural replication enabled the preparation of novel compounds with unprecedented properties. Here, we report on the characterization of a series of Delafossite-type high-entropy oxides by means of TEM, SEM, XPS, ICP-OES, Mössbauer spectroscopy, XRD including Rietveld refinement analysis, SAED and STEM mapping and discuss about the role of entropy stabilization. Our experimental data indicate the formation of uniform solid-solution structures with some Li/M mixing.