Designing Vanadium‐Based Oxide Electrocatalysts for Water Splitting: Experimental and Mechanistic Insights with Machine Learning

Abstract

Developing efficient and durable non‐precious metal electrocatalysts for electrochemical water splitting remains a critical barrier to sustainable hydrogen production. Among earth‐abundant candidates, vanadium‐based oxide electrocatalysts are highly attractive due to their wide range of oxidation states (V 2+– V 5+ ), composition‐dependent tunability of active sites, and intrinsically flexible atomic structures. This review offers a comprehensive and mechanistic analysis of the six principal modification strategies: lattice engineering, heteroatom doping, heterojunction and interface engineering, carbon‐based hybridization, morphology engineering, and surface reconstruction and pre‐catalyst design. It highlights structure–property relationships, the identification of active sites, and operative oxygen evolution pathways. A distinctive finding across the strategies reviewed is that vanadium dissolution and surface reconstruction are design features, not degradation processes; thus, the as‐synthesized material frequently functions as a pre‐catalyst engineered to reconstruct under electrochemical operating conditions. This review further highlights how machine learning methods accelerate the atomistic modeling of structurally analogous oxide systems, offering an emerging simulation framework for addressing mechanistic questions that conventional first‐principles calculations cannot address at the scale required for this materials class. Finally, a personal perspective is offered on the challenges and future research directions for advancing vanadium‐based oxide electrocatalysts toward industrially relevant water‐splitting performance.