Nitrogen and Sulphur co-doped Graphene: A Robust Material for Methylene Blue Removal

N, S co-doped graphene (NSG) has been synthesized by using graphene oxide, cyanamide and sodium sulphide as a source of C, N and S respectively. Due to its excellent electronic properties and stability, NSG has been used as an adsorbent for methylene blue (MB) removal from aqueous solution. Adsorption efficiencies of Graphene, N-doped graphene, S-doped graphene and NSG were compared during the study and it was found that NSG was the most efficient material for the adsorption of MB. The study was carried out in the UV-visible region by observing the changes in absorbance. NSG has excellent properties to adsorb the MB dye with a removal efficiency of 93.76±0.2%. Additionally, desorption studies were also carried out using 0.1 M cetylpyridinium chloride as cationic surfactant and the desorption% was found to be 50.28±0.1%, signifying its reusability as an adsorbent. This indicates that NSG opens a new window for the design of heteroatom-doped carbon material as well as its application in the adsorption studies. Accordingly, the synthesized material will be employed for wastewater treatment as a reusable adsorbent of MB in the near future with high efficiency and appreciable stability. In addition, the material has several other future applications such as electrode material for supercapacitor battery, sensor, adsorbent for metal ions and biomolecules, etc.