Emerging Issues and Opportunities of 2D Layered Transition Metal Dichalcogenide Architectures for Supercapacitors

Two-dimensional layered transition metal dichalcogenides (2D TMDs) have emerged as promising candidates for supercapacitor (SCs) owing to their tunable electronic properties, layered structures, and effective ion intercalation capabilities. Despite these advantages, challenges such as low electrical conductivity, the interlayer restacking, oxidation and structural collapse hinder their practical implementation. This review provides a comprehensive overview of recent advances in the development of 2D TMDs for SCs. We begin by outlining the charge storage mechanisms and design principles for SCs, followed by an in-depth discussion of the synthesis methods and the associated challenges in fabricating 2D TMD architectures. The subsequent sections explore their crystal structures and reaction mechanisms, illustrating their electrochemical potential in SCs. Furthermore, we highlight material modification strategies, including nanostructuring, defect engineering, phase control, and surface/interface modulation, which have been proposed to overcome existing challenges. Finally, we address critical issues and emerging opportunities for 2D TMDs to inspire the development of SC technologies.