Superhydrophobic Fabrics for Oil/Water Separation Based on the Metal-Organic Charge-Transfer Complex CuTCNAQ

The fabrication of a superhydrophobic nylon textile based on the organic charge-transfer complex CuTCNAQ (TCNAQ=11,11,12,12-tetracyanoanthraquinodimethane) is reported. The nylon fabric, which is metallized with copper, undergoes a spontaneous chemical reaction with TCNAQ dissolved in acetonitrile to form nanorods of CuTCNAQ that are intertwined over the entire surface of the fabric. This creates the necessary micro- and nanoscale roughness that often allows the Cassie-Baxter state to be obtained with high robustness, thereby achieving a superhydrophobic/superoleophilic surface without the need for a fluorinated surface. The material is characterized with SEM, FTIR spectroscopy, and X-ray photoelectron spectroscopy, and investigated for its ability to separate oil and water in two modes, namely through filtration and as an absorbent material. It is found that the fabric can separate dichloromethane, olive oil, and crude oil from water, and reduce the water content of the oil during the separation process. The fabric is reusable, highly durable, and tolerant to conditions such as seawater, hydrochloric acid, and extensive time periods on the shelf. Given that CuTCNAQ is a copper-based semiconductor, there may also be the possibility of other uses in areas such as photocatalysis and antibacterial applications.