ABSTRACT In this study, a series of mixed transition metal dichalcogenides, Mo 1‐x W x S 2 (x = 0.3, 0.5, and 0.7), were synthesized via a one‐pot hydrothermal method to engineer controllable 2D–2D heterostructures through a substitution strategy. The incorporation of W into the MoS 2 lattice induces basal‐plane disorder, expanded interlayer spacing, and a high density of lattice defects in the resulting Mo 1‐x W x S 2 systems. XRD, Raman, and XPS analyses collectively confirm the emergence of a mixed‐metallic 1T/2H phase and distortion in the S‐Mo/W‐S stacking, validating the formation of a hetero‐layered 2D–2D architecture across all compositions. Electron microscopy reveals a clear transition from aggregated MoS 2 nanopetals to an increasingly intertwined and interconnected 2D‐sheet‐like network, with the Mo 0.5 W 0.5 S 2 composition exhibiting the most optimized heterolayer‐assembly and enhanced surface area. Benefiting from this engineered 2D–2D framework, Mo 0.5 W 0.5 S 2 delivers a high specific capacitance of 559 F g −1 at 1 A g −1 , nearly double that of pristine‐MoS 2 . A symmetric‐supercapacitor device fabricated using this optimized electrode achieves an energy density of 24.1 Wh kg −1 at a power density of 866.6 W kg −1 and retains 88.4% capacitance with 100% coulombic efficiency after 10,000 cycles. These features collectively enable fast ion‐transport in the system, thereby enhancing the electrochemical performance of the developed supercapacitor device.
Moorthi et al. (Fri,) studied this question.