Enhancing OER Electrocatalytic Performance via Configurational Entropy-Tuned Formation of Short-Range Ordered Quantum Dots in Medium-Entropy Compounds

Medium-entropy compounds (MECs) have attracted significant interest thanks to their exceptional mechanical, physical and chemical properties, which are associated with their unique atomic structures. In this study, we enhanced the performance of MECs by optimizing their configurational entropy, leading to the formation of abundant quantum dots (QDs) and improved catalytic activity. This structural optimization not only adjusted electronic properties but also boosted catalytic performance and stability in oxygen evolution reactions (OER). MEC-Fe 2.0 catalyst demonstrated a low overpotential and outstanding long-term stability compared to others. Density functional theory simulations revealed that the incorporation of Co and Ni atoms increased the configurational entropy and facilitated the formation of short-range ordered QDs. This modification effectively lowered the chemical activity of Fe site, contributing to the enhanced catalytic performance. This design approach provides a promising strategy for advancing MEC, offering a pathway to improve their catalytic efficiency for various applications.