Synthesis and electrochemical study of MoS2/MoO3 and MoS2/CNTs binary composites for supercapacitor applications

Ultrasonication-assisted MoS2/MoO3 and MoS2/CNT composite materials were synthesized to improve the electrochemical performance of MoS2. The morphological characterization of the synthesized materials, including MoS2, MoO3, carbon nanotubes (CNTs), and binary composites, was conducted using scanning electron microscopy, the structural characterization using X-ray diffraction, and the chemical characterization using Energy Dispersive X-ray spectroscopy and Raman spectroscopy. The results revealed unique structures, compositions, and crystalline arrangements of the materials. Electrochemical studies were employed to investigate the electrochemical properties of MoS2, MoO3, and their binary composites. MoS2/MoO3 exhibited superior specific capacitance values compared to MoS2/CNTs, indicating enhanced charge storage capabilities. The MoS2/MoO3 and MoS2/CNTs composites demonstrated superior electrochemical performance compared to individual MoS2 and MoO3 materials, with specific capacitances of 137.65 F/g and 62.35 F/g, respectively, at 0.5 A/g. The stability of the supercapacitor devices was assessed over an extended cycling period of 5000 cycles, each at a current load of 2 A/g. The devices demonstrated commendable capacitance stability, retaining 75.5% of their initial capacitance over the entire cycling period. The observed enhancement is attributed to the synergistic integration of MoS2 and MoO3, wherein MoS2 provides a high surface area, while MoO3 contributes fast and reversible redox activity. This complementary interaction facilitates improved charge transfer, increased active sites, and enhanced ion diffusion within the composite architecture.