MXene as Robust Support for Comprehensive Oxygen Electrocatalysis: Mechanistic Perspective and Material Advances in OER, ORR, and Bifunctional Activity

ABSTRACT Catalyst support materials play an important role in oxygen electrocatalysis by providing a stable platform to disperse and anchor electrocatalysts for their enhanced activity and durability. MXenes, a class of two‐dimensional van der Waals materials, have gained significant attention as support materials in oxygen electrocatalysis due to their exceptional conductivity, hydrophilicity, tailorable surface functionality, and mechanical stability. This review highlights the role of MXenes as the support for the whole spectrum of oxygen electrocatalysis, including the Oxygen Evolution Reaction (OER), Oxygen Reduction Reaction (ORR), and bifunctional activity. We begin by discussing the fundamental properties of MXenes that make them effective catalyst supports, followed by a mechanistic analysis of OER in both alkaline and acidic environments. Recent advancements in MXene‐supported catalysts for OER are reviewed, focusing on their impact on reaction kinetics and stability. Similarly, we examine ORR mechanisms in different media, detailing both the two‐electron and four‐electron pathways and the role of MXenes in optimizing selectivity and efficiency. Further, we discuss the bifunctional catalytic performance of MXene‐based systems, highlighting their potential applications in metal–air batteries. The review ends by outlining the major challenges that remain and offers perspectives on future research paths to further improve the performance of MXene‐based catalysts.