High-Entropy Nanomaterials for Electrochemical Energy Conversion and Storage

High entropy materials (HEMs) with a single-phase structure have introduced a brand-new area of research in electrochemical energy conversion and storage devices. The fusion of divergent elements has been found to produce synergistic effects with advanced physicochemical phenomena. As such, heterometallic equiatomic proportion-based nanomaterials with stabilized configurational mixed entropy exhibit distinguished characteristics to enhance electrode catalytic activity and storage capability. This critical review summarizes the recent advances in developing HEMs at the nanoscale using different synthetic technologies. The most popular types of HEMs are high entropy alloys (HEAs) and high entropy oxides (HEOs), both of which present tunable structural properties. This review pays particular attention to recapitulating the necessary considerations to obtain HEAs effective for water splitting, fuel cell operation, CO2 reduction reactions, and energy storage applications. The demonstrated examples bestow a deep understanding of efficient HEM utilization as electrocatalysts and electrodes for charge storage devices. Finally, challenges and future perspectives pertaining to HEMs adoption as desirable materials for electrochemical energy conversion and storage devices will be discussed.