Synthesis and Electrochemical Performance of Spinel Crystal Structured ((FeNiCrMn)1-xCox)3O4 (x=0.1, 0.2, 0.3) High Entropy Oxides

Abstract

High entropy oxides are a new class of materials with a single-phase structure consisting of five or more components. Due to their high structural stability and electrochemical performance, they have attracted a lot of attention in recent years. In this study, high entropy oxides with the composition ((FeNiCrMn)1-xCox)3O4 (x=0.1, 0.2, 0.3) were synthesized using the solid state method and their electrochemical performances as anode material for lithium-ion battery were investigated. Spinel crystal structured of high entropy oxides were characterized by X-ray diffraction (XRD) technique. The electrochemical performance of anodes were evaluated by assembling CR2016 type coin cell. As a result of galvanostatic charge/discharge experiments the initial discharge capacities of ((FeNiCrMn)1-xCox)3O4 (x=0.1, 0.2, 0.3) anodes at a current density of 50 mA g-1 werecalculated as 1993 mA h g-1, 1651 mA h g-1 and 1706 mA h g-1, respectively. Among the synthesized high entropy oxide anodes, the ((FeNiCrMn)0.9Co0.1)3O4 anode shows high initial discharge capacity, while their capacity retention rates at the end of 10th cycle were calculated as 53.9%, 55.1%, 59.7%. This study clearly indicates that the electrochemical performances of high entropy oxide anodes are affected by the Co content.