2H-1T WS2/rGO/MWCNT Nanocomposites for High-Performance Supercapacitors

The exploration of transition metal dichalcogenides (TMDs) has revolutionized the field of energy storage. Among the various TMDs, tungsten disulfide (WS2) is of particular interest for energy storage, especially in supercapacitor (SC) applications. WS2 exhibits two primary crystallographic phases: the semiconducting 2H phase and the metallic 1T phase. The 1T phase offers superior conductivity and abundant active sites, making it advantageous for improving electrochemical performance. However, challenges such as layer restacking, phase stability, and scalability hinder its application. In this study, we developed an advanced WS2/rGO/MWCNT hybrid composite by exfoliating WS2 nanosheets and integrating reduced graphene oxide (rGO) and oxidized multiwalled carbon nanotubes (MWCNTs) to address these challenges. The rGO and MWCNT synergistically prevented layer restacking, enhanced ionic mobility, and promoted a stable mixed 2H-1T WS2 phase. Electrochemical performance evaluation demonstrated a significant enhancement in specific capacitance, with the WS2/rGO/MWCNT hybrid achieving 198.5 F g– 1 at 0.5 A g– 1, outperforming the bare WS2 and WS2/rGO composites. The hybrid material exhibited excellent energy storage capabilities in SC devices, achieving a specific energy of 8.17 Wh kg–1 at a power density of 3679 W kg–1 and maintaining an energy density of 9.7 Wh kg–1 at a power density of 400 W kg–1. These findings underscore the potential of WS2/rGO/MWCNT composites for high-performance energy storage applications.