In recent years, high-entropy oxides (HEOs), especially those with spinel structures, have emerged as a new class of materials for lithium-ion battery anodes. Due to the unpredictable nature of these materials, it is crucial to synthesize and investigate various compounds. The effects of different elements in HEOs and their single-phase and multi-phase structures on the properties of HEOs are not yet fully understood. In this study, two HEOs with equimolar compositions (Mg0.2Ti0.2Zn0.2Ni0.2Fe0.2)3O4 and (Mg0.2Cr0.2Zn0.2Ni0.2Fe0.2)3O4 were prepared using a simple solid-state method. The effects of Ti and Cr elements on the material characteristics and their electro- chemical performances were investigated. It was found that the properties of the materials change with varia- tions in their elemental composition. X-ray diffraction (XRD) results show that the compound (Mg0.2Ti0.2Zn0.2Ni0.2Fe0.2)3O4 has a single-phase spinel structure, while (Mg0.2Cr0.2Zn0.2Ni0.2Fe0.2)3O4 contains two phases: spinel and rock-salt. Morphological analysis of the two samples reveals that the grain shapes are more uniform in the (Mg0.2Ti0.2Zn0.2Ni0.2Fe0.2)3O4 sample. The superior electrochemical performance of (Mg0.2Ti0.2Zn0.2Ni0.2Fe0.2)3O4 as an anode material, achieving a reversible specific capacity of 327mAh g 1 at 1000 mA/g, can be attributed to its single-phase structure, uniform morphology, and the stabilizing effect of Ti during cycling.

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