Efficient water disinfection using hybrid polyaniline/graphene/carbon nanotube nanocomposites

Pathogens, such as Escherichia coli (<i>E. coli</i>) and Staphylococcus aureus (<i>S. aureus</i>), contaminate water resources and are the main causes of diseases, not just waterborne diseases. The present study aims to fabricate hybrid materials composed of polyaniline (PANI), graphene nanosheets (GNs), and carbon nanotubes (CNTs) and utilize the materials for water disinfection. Thus, a new class of hybrid nanocomposites (PANI/GN/CNTs_a-e) was fabricated under ultrasonic conditions following a well-known <i>in situ</i> oxidative polymerization technique in an aqueous acidic solution. A homogeneous mixture of GNs and CNTs (40/60 weight %) prepared at 2, 5, 10, 20 and 30% fixed ratios of GNs/CNTs was utilized in the fabrication of the nanocomposites. The structure of this new hybrid class of materials was confirmed by various characterization techniques that were utilized to corroborate their assembly. Column removal studies with bacteria indicated that the removal percentages of <i>S. aureus</i> and <i>E. coli</i> were 99.5 and 99.2%, respectively, using PANI/GN/CNTs_e. The bacterial count is an indication of bacterial removal after and before adsorption. Additionally, the data indicated clear synergic effects among the nanocomposites. Reuse studies revealed that the same percentage of adsorption was obtained for four cycles, which shows the PANI/GN/CNTs_e nanocomposites can be reused and recycled for a number of cycles with almost the same bacterial adsorption capability.