- 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
Layered Delafossite-type Lix(M1M2M3M4M5…Mn)O2 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., LiNixCoyMnzO2 [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.