The sulphur is also presumed as the important as well as the interesting candidate for doping over graphene element. As the van der Waals radius of sulphur (180 pm) is close to that of carbon (170 pm), the substitutional doping is the most preferred for the sulphur atom. Also, the polarisation of C-S bond is minimum as the electronegativity of sulphur is almost close to that of carbon . Theoretical studies predicted that the S-doping happened on graphene in two step process. They are (i) generation of defect sites and (ii) cleavage of S=S bond .