A Comprehensive Review of High‐Entropy Alloys for Supercapacitor Application

With distinct compositional, morphological, and structural characteristics, high‐entropy alloys (HEAs), a novel class of materials, present a huge opportunity among the variety of materials accessible for electrochemical applications. At least five elements (such as Fe, Co, Ni, Cu, Cr, Mn, and Zn) make up HEAs, which are known to enhance their capacity for energy storage. Thus, the HEAs’ quinary construction helps to boost their energy storage capability. Furthermore, the specific capacitance is further increased by effective ion diffusion made possible by atomic‐scale synergistic effects, optimized shape, and pore dispersion. This review explores the use of high‐entropy alloys as electrode materials for supercapacitors and clarifies how they store charge. In addition, it dives into HEA synthesis methods with an emphasis on the Fe – Co–Ni (XY) system, in which X stands for Cu, Cr, and Y for Mn and Zn. Comprehensive characterization techniques, such as X‐ray photoelectron spectroscopy, shed light on the oxidation states of certain quinary elements. By unraveling the intricacies of HEAs, this review aims to inspire further research and innovation in the field of supercapacitor.