The Influence of Prolonged High-Concentration Ozone Exposure on Superhydrophobic Coatings in Static and High-Speed Flow Atmospheres

Materials (Basel). 2022 Aug 19;15(16):5725. doi: 10.3390/ma15165725.

Abstract

The durability of superhydrophobic coatings under exposure to adverse factors that accompany their exploitation in natural and industrial environments remains a key problem in materials science. One such factor is a notable ozone concentration which can be generated as a result of corona discharge, dielectric barrier discharge, piezoelectric direct discharge, UV light photochemical processes, and others characteristic of the power industry. In this work, the mechanisms of degradation of the superhydrophobic coatings under prolonged exposure to high ozone concentrations at dynamic and nearly static conditions were studied. Our results indicate that in dynamic conditions, when the coatings are subjected to joint action of erosion loads initiated by the high-speed flow of the atmospheric air enriched with ozone, with ozone oxidation activity, the superhydrophobic state degrades quite rapidly. At the same time, in nearly static atmospheric conditions with the same ozone content, the degradation is substantially lower. Our study reveals the role of various factors such as the degradation of the layer of the hydrophobic agent, mechanical deterioration of texture, adsorption of ozone, and contact with water in the discovered behavior of the superhydrophobic coatings.

Keywords: durability; erosion-corrosion; functional materials; hydrophobic molecules desorption; oxidation; ozone; superhydrophobic.