Transition metal dichalcogenides (TMDC): an alternative for graphene based energy storage technology

Supercapacitors represent one of the most ideal candidates for green energy storage because of their high power density, very high cycling life and safety of operation. Having a very high specific surface area, TMDCs have the potential to store huge amount of charge and their theoretical specific capacitance is even beyond graphene. In this report layer structure of WS₂ has been synthesized by one step wet chemical route. The synthesized sample was characterized by XRD, BET and SEM micrograph confirming the morphology of the sample. Surface area as high as 203.397m² g^-1 of the as synthesized sample has been obtained. Galvanostatic charging-discharging have been performed on different batches of samples and the curves show symmetric saw tooth nature. Further, cyclic voltametry curves show near rectangular nature confirming the perfect electrode nature for supercapacitor. The highest capacitance value of 410 F/g at 200 mA/ g current density has been obtained which goes on decreasing with increasing current density. (author)