Synthesis of UMCNOs from MWCNTs and analysis of its structure and properties for wastewater treatment applications

Multi-walled carbon nanotubes (MWCNTs) are non-polar carbon tubes having poor dispersion capability in different solvents. To overcome this limitation, the oxidative unzipping of MWCNTs was done and results in the preparation of unzipped multi-walled carbon nanotube oxide (UMCNOs). The UMCNOs was characterized using field-emission scanning electron microscope, Fourier transformed infrared spectrophotometer, and X-ray diffractometer. The hybrid structure was able to improve the accessible areas significantly due to the availability of both outer and inner walls of MWCNTs. UMCNOs-cotton sponge was prepared by dipping commercial cotton in unzipped carbon nano-oxide dispersion and drying in a vacuum oven. UMCNOs-Cot sponge exhibits hydrophilic and hydrophobic properties at different conditions showed its amphiphilic nature. Hydrophobic properties of UMCNOs lower the interfacial energy of the coated cotton surface with a maximum water contact angle of 145° and super-oleophilicity showed the absorption capacity of oil from an oil/water mixture. These UMCNOs-Cot sponges were applied for the separation of oils, organic solvents with absorption capacities in the range of 21–43 times as compared to its weight. A significant loss of bacterial cell viability up to 99% was also achieved with this UMCNOs-Cot sponge.