Polydimethylsiloxane based sustainable hydrophobic/oleophilic coatings for oil/water separation: A review

Recently, engineered surfaces with special wetting behavior such as superhydrophobic and superoleophilic have gained remarkable attention of scientific community for efficiently oil/water separation application. In general, for the fabrication of surfaces with superhydrophobic and superoleophilic behavior, two things are highly essential: (1) Low surface energy, (2) high roughness. Among the utility of various coating materials, polydimethylsiloxane (PDMS) has been explored for the hydrophobic coatings on various types of surfaces because of its several specific properties such as low-surface energy agent, eco-friendly, strong adhesive ability on versatile surfaces, long term thermal and chemical durability, rapid and facile coating formation ability. Therefore, we summarized recent studies on PDMS coatings with special wetting properties (superhydrophobic/superoleophilic) on the surface of various substrates for oil/water separation. The coating fabrication approaches, treatment effects, durability of coating surfaces and oil/water separation efficiency are discussed.