Background: Molybdenum disulfide (MoS2) is a transition metal dichalcogenides and has
some interesting and promising properties. MoS2 has direct and indirect band gaps depending on its
crystalline structure. In addition, its sheets morphology makes it a good candidate for supercapacitor
Objective: The aim of this work is to study the effect of MoS2 flakes size on its optical and electrochemical
Method: MoS2 with different flakes sizes were prepared by exfoliation method. The exfoliation was
performed by sonication of MoS2 powder in N,N-Dimethylformamide followed by different centrifugation
speeds. UV-Vis spectra illustrated the optical energy gap was inversely proportional to
the MoS2 flakes size.
Results: Absorption coefficient values indicated that the exfoliation reduced the number of layers.
Symmetric supercapacitor was made from two MoS2 electrodes and tested in 6 M KOH electrolyte.
The specific capacitance was found to be dramatically increased with decreasing flakes size (9.5 and
4.5 mF/cm2 for 0.26 and 0.98 µm flakes size, respectively).
Conclusion: These findings recommend that MoS2 can be the excellent electrode material for supercapacitor.