Orbital modulation in high-entropy alloy catalysts: an effective strategy for enhancing catalytic performance

High-entropy alloy-based electrocatalysts play a vital role in diverse electrochemical reactions essential for energy conversion technologies. However, optimising their catalytic activity, durability, and operational stability remains a significant challenge. In recent years, electronic orbital modification has emerged as a key strategy for developing high-activity electrocatalysts, as it enhances the stability of the electronic structure and tunes surface reactivity. This review aims to discuss the fundamental principles and approaches of orbital modification in catalysts incorporating transition metals, with particular focus on how these strategies influence durability and catalytic activity. It also highlights seminal theoretical studies that have shaped the field in recent years. Furthermore, it examines a selection of illustrative studies that demonstrate practical strategies for achieving well-defined orbital modulation in electrocatalysts. Finally, we clarify current challenges and propose perspectives for advancing theoretical understanding and practical applications in this rapidly developing field.