Synthesis and microstructure of the (Co,Cr,Fe,Mn,Ni) 3 O 4 high entropy oxide characterized by spinel structure

Abstract A high-entropy (Co,Cr,Fe,Mn,Ni)3O4 oxide, characterized by the Fd-3m single-phase, spinel structure, was synthesized for the first time. The material was based on the combination of Co, Cr, Fe, Mn and Ni elements, well known from the other group of high-entropy materials, namely high-entropy alloys. The microstructure of the material was studied using SEM + EDS and XRD methods, showing single-phase structure. Additional structural characterization was performed with use of Raman spectroscopy, also showing in the process, the usefulness of this method for characterization of high-entropy oxides.