A stable super-amphiphilic surface created from superhydrophobic silica/epoxy coating by low-temperature plasma-treatment

A silica/epoxy hydrophobic coating (water contact angel (WCA) = 130 degrees) was prepared on a glass substrate and further treated in a low-temperature plasma (PL) condition, which surprisingly resulted in an amphiphilic surface (best WCA = 3.5 degrees, best oil CA = 5 degrees) with excellent surface stability and without decay along with the time. We systematically studied the influences of two working gases (O-2, Ar) and the working time of PL-treatment on the wetting behaviour (for both water and oil) and the aging effects of the PL-treated silica/epoxy coating, using SEM, FTIR-ATR, XPS and metallographic microscope. The results suggested that the stable super-amphiphilic change, causing by O-2 or Ar low-temperature PL-treatment, can be attributed to a physical smoother surface (bombed by PL-treatment) and the surface chemical state change (more polar groups, OH/NH2).

Automated summary

In this study, an amphiphilic surface with excellent surface stability was prepared by low-temperature plasma treatment, attributing to a physical smoother surface and a surface chemical state change. The stable super-amphiphilic change is caused by the O-2 or Ar low-temperature plasma treatment.