Superhydrophobic Cu2S@Cu2O film on copper surface fabricated by a facile chemical bath deposition method and its application in oil-water separation

Cu 2 S and Cu 2 O composite (Cu 2 S@Cu 2 O) film with micro/nano binary structure was created on copper surface using the mixing solution of sodium thiosulphate and copper sulfate by a facile chemical bath deposition method. After modification with low-cost polydimethylsioxane (PDMS), the superhydrophobic Cu 2 S@Cu 2 O film was obtained. The as-prepared film shows outstanding water repellency with a water contact angle larger than 150° and long-term storage stability. The geometric morphology and chemical composition of the film were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), respectively. Moreover, the same method was used to fabricate superhydrophobic/superoleophilic copper mesh, and it could realize separation of various oily sewages with separation efficiency above 94%. This strategy has potential to fabricate the practical superhydrophobic Cu 2 S@Cu 2 O film on copper surface on a large scale due to its simplicity and low cost.