Surfactants are greatly used to facilitate the formation of O/W emulsions and they have a noticeable effect on the emulsions stability. Recently the stability of emulsions is recently investigated in the presence of different nanoparticles. The effect of graphitic carbon nitride (g-C3N4) nanosheets on the stability of O/W emulsion in the presence of anionic surfactant SDS is studied in this work. Using equilibrium interfacial tension measurements, it was shown that g-C3N4 nanosheets are not surface active, but the interfacial tension of SDS solutions decreases by adding g-C3N4 nanosheets. The emulsion stability of oil/SDS aqueous solution in the absence and presence of g-C3N4 nanosheets was studied and it was observed that g-C3N4 nanosheets increase the stability of oil/water emulsions specially at low SDS concentrations.
