Superhydrophobic Al₂O₃/MMT-PDMS Coated Fabric for Self-Cleaning and Oil-Water Separation Application

This study introduces a novel superhydrophobic coating applied to the fabric surface through spray coating of the Al₂O₃/MMT nanocomposite and PDMS polymer to enhance the surface roughness and reduce the surface tension, respectively. The as-prepared coating exhibits a remarkable superhydrophobic property with a water contact angle (WCA) of ∼174.6° and a water sliding angle (WSA) < 5°. Notably, the fabric demonstrates a self-cleaning property through removing dust and dirt via adhering to water droplets. Moreover, the insignificant loss of WCA (3.2 and 1%) after exposure to alkaline and acidic media for 10 days verifies the promising chemical stability of the coated layer, whereas WCA > 160° after 24 h of immersion in various organic solvents further indicates the layer resistance. Besides, the layer sustains WCA of 174.5, 172.5, and 168.45° after 1 month of air exposure, ultrasonic washing, and 50 cycles of home laundry. The mechanical resistance of the fabric was verified by maintaining a WCA of 158.73° after 200 abrasion cycles. Also, the layer exhibits thermal resistance with <4.1% of WCA loss in the temperature range of -10 to 180 °C. Additionally, the superhydrophobic coating excels in oil-water separation, achieving >99% separation efficiency for various oils. These exceptional properties position the fabric for diverse applications, including protective clothing, outdoor gear, medical textiles, and sportswear, emphasizing its versatility and novelty in the realm of superhydrophobic materials.