Poly­(1H,1H,2H,2H-perfluorodecyl acrylate) (PPFDA) is incorporated within a sintered mesoporous network of TiO2 nanoparticles via initiated chemical vapor deposition (iCVD). iCVD PPFDA grows uniformly on the pore surface of the mesoporous TiO2 (25 nm pore diameter, 2–4 μm thick), resulting in up to 91% of the pore volume being filled. This leads to a high TiO2 loading (58 vol %, 67 wt %) in the PPFDA–TiO2 nanocomposite and a large decrease in the PPFDA crystallinity by >93% compared to the bulk polymer film. The significantly suppressed crystallinity is attributed to the nanoconfinement of polymer chains in the tortuous, interconnected nanopore channels that frustrates chain alignment, and from the large interfacial energy difference between PPFDA fluoropolymer and hydroxylated TiO2 that impedes heterogeneous nucleation for crystal growth.

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In some cases, surfaces can display both high water and oil repellency simultaneously, which are known as superomniphobic surfaces. Super liquid repellent coatings and surfaces are useful in a broad range of applications, including self-cleaning, [12] water-oil treatment, [13,14] fabric/textile repellency, [11,15] thermal management/latent heat transfer, [16,17] drag reduction, [18] structural insulation, [19] and fluidic devices. [20] These designed structures can be artificially constructed by various techniques like lithography, [10,21] templating/molding/imprinting, [22][23][24] plasma and chemical etching, [25,26] spin/ dip/spray coating, [11,27,28] electrodeposition/electrospinning, [29] and chemical vapor deposition. [30,31] These methods often require intricate templates, complex multistep procedures, or a combination of several different methods that are highly process-intensive in order to achieve super-repellency. For example, many studies rely on photolithography to create the liquid repellent topological relief structures, a process that requires numerous steps, such as spin coating of a photoresist, ultraviolet light exposure through a photomask, and pattern development and etching. Further, many approaches rely on liquid-based processing that present challenges related to the use of solvents, including substrate damage, solvent residue, and poor coating quality.The goal of achieving a superomniphobic coating or surface using a simple approach that overcome current processing challenges remain elusive. Here, we offer a one-step, direct and solvent-free approach for creating low surface energy textured surfaces with super liquid repellency by applying the initiated chemical vapor deposition (iCVD) process. iCVD vaporizes liquid precursors, typically monomers and initiators, to directly grow polymers on a variety of substrates. By bypassing the liquid phase, iCVD overcomes poor wettability and substrate damage often associated with liquid processing. The iCVD approach also provides precise process control and tunability to achieve desired polymer structure and properties without further post-treatment, such as removing solvent residues. The kinetics of iCVD polymerization reaction on the substrate surface is known to be controlled by monomer adsorption, i.e., the more monomer available at the surface the faster is the polymer growth. iCVD studies have shown that a simple parameter controls the overall deposition kinetics, which is the fractional saturation of monomer, z, defined as the ratio of the monomer partial pressure in the gas phase to its Highly liquid repellent (superhydrophobic, superoleophobic) surfaces are fabricated using mostly top-down approaches and liquid-based processing. Top-down approaches, like lithography and templating, are highly processintensive, while liquid-based processing, like etching and fluoropolymer solution coating, rely on solvents that often damage the substrate. Ultimately, to suppress liquids from spreading, the goal is to create a surface with low surface energy ...

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