A slew of different liquids bead up on this strip of cotton fabric because of a coating that researchers applied to it (droplets from left, water containing a blue dye; oleic acid, which is the main component in olive oil; milk; and coffee). Also, with the coating, the fabric can conduct electricity, allowing the researchers to incorporate it into an electrical circuit that turns on a light-emitting diode (top right). Junqi Sun’s team at State Key Laboratory of Supramolecular Structure & Materials made this multitasking coating by first applying a layer of copper that’s about 10 µm thick. This layer gives the threads their conductivity. Then the researchers dip the copper-coated cotton in an ethanol bath that contains two chemicals with fluorinated side chains. The chemicals bind to the copper surface, and because of the molecules’ highly water- and oil-repellent side chains and the copper’s rough surface texture, the fabric staves off a wide variety of liquids. Fabrics with coatings like these could one day be used with wearable electronics and sensors.
Credit: Xiang Li.
Read the paper: ACS Appl. Mater. Interfaces 2018, DOI: 10.1021/acsami.8b01279
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