RMS roughness-independent tuning of surface wettability by tailoring silver nanoparticles with a fluorocarbon plasma polymer

Abstract

A layer of 14 nm-sized Ag nanoparticles undergoes complex transformation when overcoated by thin films of a fluorocarbon plasma polymer. Two regimes of surface evolution are identified, both with invariable RMS roughness. In the early regime, the plasma polymer penetrates between and beneath the nanoparticles, raising them above the substrate and maintaining the multivalued character of the surface roughness. The growth (β) and the dynamic (1/z) exponents are close to zero and the interface bears the features of self-affinity. The presence of inter-particle voids leads to heterogeneous wetting with an apparent water contact angle θ = 135°. The multivalued nanotopography results in two possible positions for the water droplet meniscus, yet strong water adhesion indicates that the meniscus is located at the lower part of the spherical nanofeatures. In the late regime, the inter-particle voids become filled and the interface acquires a single valued character. The plasma polymer proceeds to grow on the thus-roughened surface whereas the nanoparticles keep emerging away from the substrate. The RMS roughness remains invariable and lateral correlations propagate with 1/z = 0.27. The surface features multiaffinity which is given by different evolution of length scales associated with the nanoparticles and with the plasma polymer. The wettability turns to the homogeneous wetting state.

The evolution of Ag nanoparticles inside a gas aggregation cluster source

“…The application of two or even three magnetrons in the same aggregation chamber enabled the production of heterogeneous NPs. In spite of the huge number of studies that dealt with the gas phase preparation of metal NPs and their applications, little concern has been raised with regard to the processes occurring inside the aggregation chamber. A number of works dealing with modeling of the NP trajectories have been performed, although the experimental approaches are scarce.…”

Facile preparation of multifunctional poly(amide‐imide)/polyaniline films: Combining self‐cleaning, self‐extinguishing, and conductive

“…Solid films with controllable surface wettability have been attracted considerable attention because of their advantages in various applications such as self‐cleaning materials, thermally responsive filters, nanoscale device . Surface wettability is mainly dependent on their chemical composition and geometrical microstructures . Creating local geometric roughness and tailoring its size distribution are the most important issues besides the introduction of hydrophobic components on the material surface.…”

Gas-Phase Synthesis of Functional Nanomaterials

“…The possibility, on the one hand, to independently tune the surface chemical composition that is given solely by the properties of the overcoat material and, on the other hand, the surface roughness that is primarily given by the size and number of NPs in the base layer, paves the way for the production of nanostructured materials with well-defined interfacial properties. This enabled production of surfaces with tailor-made wettability that may range from super-hydrophilic to super-hydrophobic (e.g., [60,[266][267][268][269][270][271][272][273]), superwettable textiles for versatile oil/water separation with antibacterial properties [274] or nanostructured titanium coatings that mimic the surface roughness of a bone and, thus, facilitate the growth of osteoblasts [275]. Obviously, the sequence of deposition of NP and their subsequent overcoating may be repeated that allows for the fabrication of multiple stacks of particle and matrix layers [276].…”