MoS2 quantum dots based next-generation micro-supercapacitors

The drive for compact, high-performance energy storage has spurred research on quantum-engineered materials with ultrafast, reversible ion-electron dynamics. In this context, we demonstrate a mixed-phase 1 T/2H-MoS 2 quantum dot (QD)-based electrode prepared via a pulsed electrodeposition method, with precise control over the composition and morphology, as a potential supercapacitance. When evaluated in 0.5 M H 2 SO 4 electrolyte, the optimized electrode delivered an exceptional specific capacitance of 741 F·g −1 , accompanied by remarkable cycling stability, maintaining 89.6% of the initial capacitance over 35,000 charge-discharge cycles. Furthermore, symmetric MoS 2 QDs devices implemented in a parallel-plate configuration exhibited a capacitance of 272 F·g −1 , an impressive energy density of 112 Wh·kg −1 , a power density of 3712 W·kg −1 , and a retaining capacitance of 77% after 20,000 cycles. These results underscore the efficacy of the electrodeposition approach for tailoring mixed-phase MoS 2 QDs with synergistic metallic and semiconducting domains, enabling rapid ion diffusion and superior charge-storage characteristics. Overall, this work establishes a scalable, solution-based route toward high-performance symmetric micro-supercapacitors, paving the way for their integration into next-generation flexible and miniaturized energy storage systems. Mixed-phase 1 T/2H-MoS2 quantum dot-based electrodes prepared via pulsed electrodeposition for stable high-performance on-chip micro-supercapacitors. • Electrodeposited mixed phase 1 T/2H-MoS 2 quantum dot-based electrodes • Record capacitance of 741 F·g −1 and remarkable rate capability in aqueous electrolyte. • High energy and power densities micro-supercapacitor 112 Wh·kg −1 & 3712 W·kg −1 . • Outstanding cycling stability with 99.6% capacitance retention after 35,000 cycles. • Mixed-phase synergy enabled scalable, on-chip, high-energy microscale storage.