Durable Superamphiphobic and Photocatalytic Fabrics: Tackling the Loss of Super-Non-Wettability Due to Surface Organic Contamination

Abstract

Superamphiphobic surfaces are self-cleaning against various liquids and dirt particles but they are not resistant to trace organic contaminants, the accumulation of which on surface would cause a decline in the liquid repellency. In this work, superamphiphobic and photocatalytic fabrics are developed that allow the elimination of various organic substances from surface by using photocatalytic decomposition. The fabrics have a contact angle of 163, 156, and 158° to water, hexadecane, and sunflower oil, respectively. They are also demonstrated to be able to decompose methylene blue, oleic acid and sodium dodecyl sulfate (SDS) under UV light. The removal of human body grease or laundry detergent from surface to recover the super-non-wettability was demonstrated through the natural sunlight exposure. The slight damage on superamphiphobicity caused by the photocatalytic activity can be cured with simple heat treatment. In addition, the superamphiphobic fabrics show excellent durability against abrasion and repeated washing. The photocatalytic and heat-curing strategy reported here may bring superamphiphobic fabrics one step closer to practical application in various fields.

Biomimetic Fabrication of Janus Fabric with Asymmetric Wettability for Water Purification and Hydrophobic/Hydrophilic Patterned Surfaces for Fog Harvesting

“…Therefore, the controllable and on-demand separation of the oil/water mixture with different densities on the superwetting surface of the materials is of practical significance. The Janus material with asymmetric wettability performs superhydrophobicity on the one side and superhydrophilicity on the other side, showing various potential applications in unidirectional liquid transfer (“liquid diode”), interfacial mass transfer, and selective oil/water separation. − Generally, these Janus materials are produced by selectively or sequentially modifying one side of the material. Yang et al covered the hydrophilic TiO 2 on polyphenylene sulfide (PPS) to prepare the TiO 2 @PPS membrane and then further coated with perfluorodecyltriethoxysilane (PFDS) by a water/oil interfacial grafting to prepare an ultrathin hydrophobic layer, thereby achieving high-flux separation of oil/water emulsions.…”

Oil-immersion stable superamphiphobic coatings for long-term super liquid-repellency

“…superamphiphobic surfaces with high static contact angles (≥ 150°) and sliding angles (≤ 10°) for both water and oil have received a lot of attention from academia and industry [2][3][4][5][6][7]. To achieve these peculiar surfaces, an appropriate combination of surface morphology and low surface energy is needed [8][9][10][11][12][13]. The low surface adhesion towards a wide range of liquids, including water, low-surface-tension oils, and organic solvents, allows for the ease of their removal without leaving any residue.…”

Multifunctional Textiles Based on Three-Dimensional Hierarchically Structured TiO2 Nanowires

“…A superamphiphobic surface is the surface displaying a CA higher than 150° and a SA lower than 10° toward water and low-surface-tension organic liquids (lower than 30 mN m –1 ). , Excellent superamphiphobicity is a fine combination of surface energy, roughness, and the important role of re-entrant texture. − Various works have discussed how to produce high CA and decrease SA by reducing the solid–liquid contact area for a surface with hierarchical scales of texture (i.e., texture on two or more length scales). − Multiple scale structures are very important for increasing the surface roughness to achieve superamphiphobic fabric surfaces. , However, thus far, it is challenging to fabricate superamphiphobic surfaces with three or more hierarchical scales of texture, especially for textile fabric. At present, the most common strategy to achieve superamphiphobic fabric surfaces is the use of extremely low surface energy chemical modification (F-POSS) to compensate for the lack of sufficient surface roughness. − …”