Facile preparation of superhydrophobic cotton fabric with a photothermal conversion effect via polypyrrole deposition for oil/water separation

In recent years, offshore oil leakage incidents have occurred relatively frequently and it has been a challenge to effectively recover the oil due to its high viscosity. Herein, a novel superhydrophobic cotton fabric with a photothermal conversion effect for efficient separation of crude oil was prepared by a facile and inexpensive vapor deposition method. After the cotton fabric adsorbs Fe3+ions, stearic acid (SA) with low surface energy is introduced into the fabric. Then the pyrrole monomers were polymerized to polypyrrole (PPy) by Fe3+ ions through vapor deposition method to obtain a fabric with photothermal properties and superhydrophobicity. The modified fabric showed good abrasion resistance, acid/alkali resistance, and self-cleaning properties. In addition, the modified fabric exhibited excellent photothermal conversion performance, and its surface temperature was able to increase from 30.0 °C to 59.5 °C in 2 min, and reached 68.2 °C in 5 min under simulated sunlight. Finally, three kinds of oil-water separation methods were adopted to separate oil from water with different viscosities, and all of them showed high separation efficiency, with the maximum reaching 99.4%. Under the simulated sunlight, the modified fabric could reduce the crude oil viscosity through photothermal conversion effect, so as to improve the efficiency of selectively absorbing crude oil from water, which increased from 83.2% to 91.8%.