Control over Water Adhesion on Nanostructured Parahydrophobic Films Using Mesh Substrates

Abstract

Controlo ver water adhesion is extremely necessary for many applications in water harvesting, liquid transportation, and water/oil separation, for example. Inspiredb y natural speciess uch as rose petals and gecko feet, these properties can be controlled with the topography of surface structures. Here, we report for the first time the electrodeposition of sticking conductingp olymers forming nanofilaments or nanosheets on textured mesh substrates. We show that the presence of mesh textures can reduce the water adhesion,a lthough the adhesion still remains relativelyh igh. This is probably due to ah igh amount of air between the mesh wires and al ow amount of air on them. Moreover,i ti s also possible to control the water adhesion with the mesh openingo rb ym odifying the shape of the nanostructures. This work opens news trategies for the control of water adhesion.

Templateless electrodeposition of conducting polymer nanotubes on mesh substrates for high water adhesion

“…2. This figure shows that the best results are obtained with a mesh opening of 100 µm, in agreement with previous works [31,48,49]. Indeed, for a mesh opening of 100 µm, θ increases until to reach a maximum value for Qs = 25-50 mC cm −2 and decreases after.…”

“…The water droplet cannot penetrate the mesh if the pressure induces by the droplet is below the maximum pressure than the mesh can support. The presence of nanostructures around the mesh wire can also increase θ if the amount of air trapped is increased [31,48,49]. Here, because the nanotubes are made of hydrophilic materials and because they are not densely packed, we think that the water droplet fills the space between the nanotubes but not inside the nanotubes as shown in Fig.…”

“…Especially, the monomers of the 3, 4-ethylenedioxythiophene (EDOT) combine exceptional polymerization capacity and optoelectronic properties [29,30] with the possibility to form a large range of structured materials. Many shapes were reported in the literature including nanoparticles, nanofibers, nanosheets, flowerlike and cauliflower-like structures [31][32][33]. The monomers can also be modified with a substituent of various hydrophobicity.…”

3,4-Dialkoxypyrrole for the Formation of Bioinspired Rose Petal-like Substrates with High Water Adhesion

“…Using fluorinated doping agents, switchable surfaces from superhydrophobic to superhydrophilic were reported by a simple change in voltage . One-step processes, where the growth of structured conducting polymers is induced directly on substrates, were also reported, including preferential growth, grafting, vapor-phase polymerization, plasma polymerization, and electropolymerization. , …”

“…Electropolymerization is a very fast and controllable process for developing organized conducting polymer films. Here, a monomer is oxidized in an electrochemical cell to induce polymerization and polymer deposition on a working electrode. , Different conductive substrates can be used as working electrodes, such as platinum, gold, titanium, stainless steel, and transparent conductive glass (ITO) but not aluminum because of the presence of the oxide layer. Complex substrates such as meshes can also be used because polymerization starts from the substrate.…”