Nanoimprint Lithography Enabled Lubricant Infused Nano‐Fibrillar Slippery PVDF‐HFP for Enhanced Fog Harvesting, Anti‐Fouling and Transparency

ABSTRACT

The application of Nepenthes‐inspired slippery surfaces in practical technologies, e.g., fog harvesting and anti‐fouling, is limited by complex fabrication methods, toxic hydrophobizing agents, and limited durability. Here, an intrinsically hydrophobic poly (vinylidene fluoride‐co‐hexafluoropropylene) film (F‐PVDF‐HFP) is subjected to nanoimprint lithography to fabricate a super‐hydrophobic nanofibrillar PVDF‐HFP (N‐PVDF‐HFP; contact angle of 155° ± 2.2°). Subsequent lubricant infusion into N‐PVDF‐HFP produced nanofibrillar, slippery PVDF‐HFP (L‐PVDF‐HFP), demonstrating stable lubricant retention due to capillary forces and preferential lubricant wetting on the substrate. Fog harvesting experiments show a 32.1% higher water collection rate for L‐PVDF‐HFP than F‐PVDF‐HFP. Furthermore, L‐PVDF‐HFP exhibits remarkable repellence against common liquid foulants and suppressed E. coli and S. epidermidis adhesion. Additionally, L‐PVDF‐HFP demonstrates optical transparency with an average total transmittance of 91.7% and a haze of 26.7% across the visible spectrum. Moreover, L‐PVDF‐HFP retained sliding angles below 17° after storage under ambient conditions (30 days) and elevated temperatures (75°C, 30 days), aqueous shear (10 h), resistance to pH, long‐term foulant exposure, repeated immersion‐withdrawal cycles, abrasion (20 cycles), and UV exposure (7 h), underscoring its durability. This work enables a time‐efficient and potentially scalable approach to slippery‐surface fabrication, thereby opening a pathway to real‐world use.