Fabrication of a transparent superamphiphobic coating with improved stability

Abstract

We herein provide an effective method to fabricate a transparent superamphiphobic coating with superhydrophobicity and near-superoleophobicity, the finished coating also shows improved stability under various measurements. To do this, a transparent superhydrophobic coating was first prepared with polydimethylsiloxane (PDMS) and hydrophobic silicon dioxide (SiO2) nanoparticles. Then the coating was sintered to degrade the PDMS into SiO2 before it was further oxidized into silanol (Si–OH). Finally, the coating was treated with 1H, 1H, 2H, 2H-Perfluorooctyl-trichlorosilane (PFTS). The PFTS treated coating shows transparency, superhydrophobicity with a water contact angle of 152.7 ± 2.1° and near-superoleophobicity with a diiodomethane contact angle of 140.7 ± 3.2°. The droplets of water and diiodomethane can simultaneously slide off the surface with a sliding angle of less than 6°. Moreover, the PFTS treated coating shows a higher stability than the PDMS/SiO2 coating fabricated by spin coating under various environmental conditions. The PFTS treated coating also shows quite good stability under high temperature environment. The superamphiphobic properties, transparency and improved stability of the PFTS treated coating are systemically discussed and the results show that the finished coating may be appropriate for many outdoor applications.