Owing to the electron withdrawing nature of sulphur atom, the resultant S-doped graphene are believed to contain a wider band gap. Basically, there are two different kinds of S-doping over graphene framework. They are (i) aromatic sulphide (thiophene like sulphur, thiol and thioether) and (ii) sulfur containing oxygen functionalities (sulfoxide, sulfone and sulfonic acid) and displayed in Fig. . It has been reported that the aromatic sulphides are stable if the pyrolysis performed at 1000 °C. On the other hand, at 1000 °C, sulfoxide and sulphone groups are decomposed to liberate SO2 gas .