Design optimization of spinel-rocksalt intergrown high entropy oxide structure for enhanced electrochemical properties

Abstract

The advantages of each phase can be utilized to prepare a dual-phase intergrown anode consisting of spinel (Fd-3m) and rocksalt (Fm-3m) phases through the solid-state method. This approach leverages the high redox activity and lithium storage capacity of the rocksalt phase, as well as the good kinetics and stability of the spinel structure. By adjusting the sintering temperature, the ratio of the spinel phase (S-HEO) to the rocksalt phase (R-HEO) in the novel intergrown high entropy oxide structure (d-HEO) can be modulated, allowing for control over its electrochemical properties. Through this, an optimized S-HEO/R-HEO ratio can be achieved, resulting in high capacity coupled with desired cyclic stability and rate performance. This work demonstrates an effective strategy for constructing spinel-rocksalt intergrown structures. Furthermore, optimizing the structural properties of the dual-phase may shed light on material design for electrochemical energy storage and new applications of advanced HEOs.