Exploring the Versatility of VS ₂ and V‐Doped Materials Toward Advances in Supercapacitors, Hydrogen Evolution Reaction, and Nonlinear Optics

ABSTRACT Vanadium‐based transition‐metal dichalcogenides (TMDs), particularly VS ₂ and its derivatives, have recently attracted significant attention due to their multifunctional properties arising from their rich oxidation states, layered crystal structures, and abundant elemental availability. This review critically summarizes recent progress in the synthesis, structure–property relationships, and multifunctional application of VS ₂ ‐based nanomaterials, with a specific focus on energy storage, electrocatalytic hydrogen evolution, and nonlinear optical performance. The 2D layered morphology of VS ₂ provides a high surface‐to‐volume ratio, a tunable electronic structure, and abundant active sites, making it suitable for supercapacitor electrodes and efficient hydrogen evolution reaction (HER) catalysts. Key electrochemical parameters such as overpotential and Tafel slope are systematically discussed to evaluate HER performance. In addition, the nonlinear optical response of VS ₂ and related vanadium‐based materials is analyzed using the Z‐scan technique, where open‐aperture and closed‐aperture measurements reveal nonlinear absorption and refractive behavior, including reverse saturable absorption and self‐defocusing effects relevant to optical limiting applications. By integrating insights from these three distinct yet interconnected application domains, this review highlights the versatility and emerging importance of vanadium‐based TMD nanostructures. The comprehensive discussion presented here aims to enhance the visibility of VS ₂ ‐based materials and provide guidance for their future development in multifunctional nanodevices.