Eco-Friendly and Safe Method of Fabricating Superhydrophobic Surfaces on Stainless Steel Substrates

Industries are forced to explore more eco-friendly and safer processing methods to cope with increasing environmental issues. One of them is the fabrication of superhydrophobic stainless steel surfaces in the food industry. Current methods of fabricating superhydrophobic stainless steel surfaces have disadvantages, including using various toxic chemicals and fluorinated modifications, which cause hazards and environmental pollution, thereby limiting the application in the food industry. In this paper, an eco-friendly and safe method is proposed for fabricating superhydrophobic surfaces on stainless steel substrates using vacuum evaporation, chemical replacement reaction, and heating. The as-fabricated surface shows good superhydrophobicity with a water contact angle (WCA) of up to 155.7 degrees as well as a water slide angle (WSA) as low as about 0 degrees. Meanwhile, repellency to acidic and alkaline liquids, durability, self-cleaning, and antifouling properties are studied. Besides, the carbon content and its effect on wettability of the samples before and after heating at different temperatures are deeply investigated. The proposed method is an alternative approach for fabricating superhydrophobic stainless steel surfaces for application in the food industry without any environmental pollution.