Towards Sustainability: An Eco-Friendly Approach for Durable Anti-Icing Superhydrophobic Surfaces.

The growing interest in flexible superhydrophobic surfaces extends beyond various practical applications like solar panels, flexible electronics, etc. This study introduces a cost-effective and environmentally friendly method to create a durable, flexible, and optically semi-transparent superhydrophobic film with an extreme anti-icing character. The prestrained polydimethylsiloxane film subjected to biofuel-based flame treatment under controlled conditions induces microwrinkles with a superimposed cluster of nanoparticles while maintaining surface flexibility and transparency. This meticulous process enhances surface roughness, achieving superhydrophobic characteristics (θ > 165˚) with a remarkably low tilting angle (<3˚) with adhesion against water <2 µN (lower than Lotus leaf). The films applied over solar panels result in <1% voltage drop within 5 s due to effective cleaning under simulated rain. The remarkable anti-icing performance of the developed film is characterized by ice adhesion <25 kPa over 50 icing/de-icing cycles attributed to the presence of nanoclusters. The films displayed exceptional resilience and sustained efficacy under prolonged exposure to harsh external environments. These superhydrophobic films, characterized by flexibility, durability, and transparency, present promising opportunities for fabricating structures, even with intricate geometries. These findings imply a significant stride in the practical utilization of superhydrophobic surfaces, demonstrating their potential in diverse real-world applications.

Sustainable Manufacturing of Multifunctional Fluorine-Free Superslippery Flexible Surfaces.

Surface contamination and friction result in significant energy losses with widespread environmental impact. In the present work, we developed fluorine-free super-slippery surfaces employing environmentally friendly and simple biofuel-based flame treatment of polydimethylsiloxane (PDMS). Through a unique combination of processing parameters, highly transparent (>90%) and flexible films were engineered with omniphobic, anti-icing, and ultra-low friction properties. The processed films showed an extremely low tilting angle (<5°) and contact angle hysteresis (<4°) against different liquids, even under subzero temperatures. The coefficient of friction (COF) reduced to 0.01 after processing compared to ∼1 for PDMS. Extremely low ice adhesion of <20 kPa and enhanced freezing time ensured anti-icing behavior. The exceptional multidimensional traits were derived from the extremely stable silicone lubricant layer ensured by the hierarchically structured wrinkles. Wind tunnel tests showed that an air drag velocity of less than 0.5 m/s was sufficient to initiate droplet motion, highlighting low interfacial friction that leads to an anti-staining nature. Sustaining the self-cleaning and anti-staining characteristics, the processed surface showed utmost durability under different harsh conditions. The super-slippery surfaces with multifunctional characteristics fabricated through a sustainable route can be effectively used for various engineering and industrial applications.