Progresses of the research on spinel high entropy oxides

As a new oxide system developed in recent years, spinel high entropy oxides (S-HEOs) have two different Wyckoff sites, which allow the coexistence of trivalent and divalent cations at the same time. Such a feature increases the range of valence changes and expands the tunability of the performance. Due to its component tunability, single-phase structure and excellent thermal, magnetic, electrical properties, S-HEOs have attracted the attention of researchers at home and abroad, and has been widely used in batteries, catalysis, energy storage and other fields. In this paper, the latest research progress in the field of S-HEOs is reviewed, and the purpose of this paper is to analyze and summarize the research trends in the field of S-HEOs, especially their single-phase formation ability, preparation methods and applications.