Fabrication of superhydrophobic surface on stainless steel by two-step chemical etching

A two-step chemical etching method for preparing superhydrophobic surfaces on stainless steel substrates is proposed. The stainless steel substrates were sequentially immersed in hydrochloric acid and ferric chloride solutions to create micro-nano structures, and then the surfaces were modified with low surface energy substances. Superhydrophobic surfaces with a contact angle of 159° and a sliding angle of 2° were prepared by varying the etching solution parameters. The fabricated superhydrophobic surfaces showed excellent stability and self-cleaning properties. This paper illustrates a low-cost and efficient chemical etching method that can be used for large-area surface fabrication.