Metal‐Free High‐Entropy Materials for Energy Storage Applications

The growing demand for functional materials in energy storage has prompted significant scientific and technological initiatives. High-entropy materials (HEMs) have emerged as a promising category for a variety of applications, particularly in energy storage. They are distinguished by their high configurational entropy, resulting from the inclusion of multiple cations or anions, which leads to exceptional stability, customizable functionality, and enhanced performance in energy-related uses. Their outstanding electrocatalytic activity, coupled with strong cyclic stability and durability, makes them especially appealing for energy storage devices. Recently, there has been an increasing interest in metal-free HEMs, which are considered more sustainable alternatives to noble metals. This chapter commences with an overview of metal-free HEMs in the energy domain, covering their classification, advanced synthesis, and characterization and discussing their advantages and limitations in various energy storage systems, including supercapacitors, dielectric capacitors, and different types of battery applications.