One-step immersion for fabrication of superhydrophobic/superoleophilic carbon felts with fire resistance: Fast separation and removal of oil from water

The paper reports on a simple, low cost, and easy to perform methodology for the preparation of superhydrophobic/superoleophilic carbon felts. The technique relies on a one-step immersion process of carbon felt in 4-(heptadecafluorooctyl)aniline ethanolic solution for 24 h at room temperature. The functionalized carbon felt surface displays a superhydrophobic character with a static water contact angle higher than 150°. Importantly, the superhydrophobic property is retained upon immersion of the surface for 1 day in harsh environments over a pH range of 1–14, in salt solutions such as KCl, Na₂SO₄, MgCl₂, ZnSO₄, and in various organic solvents such as hexane, toluene, acetone, chloroform, diethyl ether and DMSO. Additionally, the modified carbon felt exhibits good thermal stability and flame retardant properties. In fact, igniting an ethanol-soaked carbon felt has no impact on the material shape/morphology after burning the ethanol away. Finally, the superhydrophobic/superoleophilic properties of the carbon felt are successfully applied for fast and efficient organic solvent separation from water. The high performance of the carbon felt associated with the simple and cost-effective functionalization process hold great promise for potential applications in environmental remediation.