Prolonging the lifetime of superhydrophobic surfaces is required so that the materials can be used practically. Thus, great efforts have been made in designing surfaces that maintain micro- and nanoscaled hierarchical structures and low surface-energy property, which are necessary for superhydrophobicity, during use. It was demonstrated that improving surface mechanical strength to increase wear resistance helps maintain hierarchical roughness, retarding the loss of superhydrophobicity. Additionally, designing self-healing materials that can recover their structure and/or properties when damaged has been suggested and demonstrated to sustain the superhydrophobicity of surfaces. This review focuses on recent advances in developing mechanically durable, corrosion-resistant, self-healing, and easily repairable superhydrophobic surfaces, which will enable prolonged lifetime of superhydrophobicity for practical applications in the future.
1 February 2010 in Science and Technology of Advanced Materials
This review summarizes the key topics in the field of large-area fabrication of superhydrophobic surfaces, concentrating on substrates that have been used in commercial applications. Practical approaches to superhydrophobic surface construction and hydrophobization are discussed. Applications of superhydrophobic surfaces are described and future trends in superhydrophobic surfaces are predicted.
A robust, self-healing superhydrophobic poly(ethylene terephthalate) (PET) fabric was fabricated by a convenient solution-dipping method using an easily available material system consisting of polydimethylsiloxane and octadecylamine (ODA). The surface roughness was formed by self-roughening of ODA coating on PET fibers without any lithography steps or adding any nanomaterials. The fabric coating was durable to withstand 120 cycles of laundry and 5000 cycles of abrasion without apparently changing the superhydrophobicity. More interestingly, the fabric can restore its super liquid-repellent property by 72 h at room temperature even after 20000 cycles of abrasion. Meanwhile, after being damaged chemically, the fabric can restore its superhydrophobicity automatically in 12 h at room temperature or by a short-time heating treatment. We envision that this simple but effective coating system may lead to the development of robust protective clothing for various applications.
1 July 2008 in Science and Technology of Advanced Materials
By coating fibers with titania sol to generate a dual-size surface roughness, followed by hydrophobization with stearic acid, 1H,1H,2H,2H-perfluorodecyltrichlorosilane or their combination, hydrophilic cotton fabrics were made superhydrophobic. The surface wettability and topology of cotton fabrics were studied by contact angle measurement and scanning electron microscopy. The UV-shielding property of the treated fabrics was also characterized by UV-vis spectrophotometry.