Fe3O4 nanoparticles functionalized GO/g-C3N4 nanocomposite: An efficient magnetic nanoadsorbent for adsorptive removal of organic pollutants

Contamination of toxic organic pollutants is a worldwide problem and needs to develop an eco-friendly and highly effective adsorbent material for its removal. Recently, 2D graphene oxide (GO) and graphitic carbon nitride (g-C3N4) is mostly used as an adsorbent for the efficient removal of organic pollutants. Here we have prepared a novel 2D/2D GO/g-C3N4 sheets decorated with Fe3O4 nanoparticles (GO/g–C3N4–Fe3O4) using the hydrothermal method. The structural properties, formation, morphology, and bonding were analyzed by different analytical techniques. Then the obtained GO/g–C3N4–Fe3O4 nanocomposite was used as an adsorbent to eliminate both toxic tetracycline (TC) antibiotic and methylene blue (MB) dye. The adsorption of TC and MB were pH-dependent and maximum adsorption capacity (120 mg/g) was achieved at pH = 3 for TC and (220 mg/g) at pH = 9 for MB. The high adsorption efficiency of GO/g–C3N4–Fe3O4 for TC and MB was mainly due to π-π and hydrogen bonding interaction. The introduction of Fe3O4 nanoparticles onto 2D/2D GO/g-C3N4 not only increases the adsorption capacity but also can make it easily separable from treated water. Adsorption data obtained were best fitted to the Langmuir and pseudo-second-order kinetics model. The adsorbed TC and MB on GO/g–C3N4–Fe3O4 surface were recovered and can be reused up to 5 cycles.