Research on the method of enhancing the hydrophobicity of planar and columnar-curved ceramic by atmospheric pressure plasma jet

Atmospheric pressure plasma jet (APPJ) possesses distinctive advantages on the surface treatment with non-planar structure. Current researches concentrate on the improvement of planar surface properties, while further study is required to investigate the influence of surface geometry on treatment methods and effect. In this article, comparative studies of the hydrophobic treatment on planar and columnar ceramic surface with APPJ are carried out. The Ar plasma jet is excited with a nanosecond pulse power, and the influence of treatment material shape on discharge characteristics is studied with discharge waveforms and images. The precursor PDMS is mixed with Ar to conduct hydrophobic treatment on the planar and columnar ceramic materials, respectively. The treatment effects are compared and analyzed through the measurement of the water contact angle (WCA) on the ceramic. The results suggest that the distribution of WCA is remarkably influenced by the treatment distance and the superhydrophobic treatment effect is achieved in the range of 10 ∼ 20 mm treatment distance. In addition, the surface treatment areas vary in shape on planar and columnar surfaces, but both present an obvious layering phenomenon, which is discussed based on surface physicochemical properties. The investigation of dynamic treatment on planar and columnar ceramic surfaces is carried out to provide guidance for industrial applications of APPJ for uniform superhydrophobic treatment effect on non-planar material surfaces.