High-entropy materials for sodium-ion batteries

The high-entropy concept is receiving attention as an advanced design strategy to functionalize material properties by tuning the disorderliness of the system. High-entropy materials have garnered significant recognition in the realm of energy storage due to their versatile and diverse material properties. In recent times, there has been active exploration of traditional materials as positive electrodes in sodium-ion batteries. Nevertheless, under profound sodiated conditions, these materials tend to exhibit sluggish kinetics and unfavourable phase transitions, leading to significant capacity degradation and subpar rate capability. High-entropy concepts successfully tune the configurational entropy by adjusting the stoichiometric balance of active/inactive cations to address the drawbacks. The recent developments and research progress on high-entropy materials for sodium-ion batteries are reviewed in this article, with a focus on the advantages of configurational entropy modulation for improving electrochemical performances. The positive aspects of high-entropy cathode materials as well as the key challenges are finally outlined to realize practical sodium-ion batteries.