Micro and Nano-Texturization of Intermetallic Oxide Alloys by a Single Anodization Step: Preparation of Artificial Self-Cleaning Surfaces

Abstract

Micro- and nanostructures of Ti-γCu (γ = 0, 30, 50, 70, and 100 wt %) intermetallic alloys were produced through a single anodization step. It was found that the original alloy composition influences the final oxide morphology obtained after anodization which presented formation of a microstructure with nanotubes, nanoparticles or nanopillars on the surface. Pure Ti and Cu oxide metals and their alloys presented hydrophilic or superhydrophilic properties immediately after anodization. When the anodized pure metal and/or Ti-γCu surfaces were functionalized with trimethoxypropylsilane (TPMSi), by dipping and coating with a thin perfluorinated layer, the treated substrates became in all cases superhydrophobic (water contact angles in the range of 152-166°), showing excellent self-cleaning properties with hysteresis below 3°. These results can be explained by a combination of nanomicro morphologies with low surface energy compounds in the topmost monolayers. The decrease in hysteresis was associated with a higher M-OH bond concentration on the anodized surfaces, which allowed for more complete TMPSi coating coverage. This study also indicates that easy and effective fabrication of superhydrophobic surfaces in pure metals and alloys is possible without involving traditional multistep processes.

Permanent superhydrophobic polypropylene nanocomposite coatings by a simple one-step dipping process

“…As a result of the morphology study (SEM and profilometer), the explanation of the differences found in CAH of the prepared superhydrophobic PP samples has to be chemical in origin. Recent works carried out in our laboratory on superhydrophobic surfaces have arrived to the conclusion that chemical heterogeneity of the surface is highly important in determining contact-angle hysteresis [45][46][47]. In an attempt to understand the differences in the dynamic component of the superhydrophobic surfaces prepared, surface chemical composition data were obtained by FTIR-ATR and XPS measurements.…”

“…Surfaces with high Ti-OH concentrations will increase the work of adhesion and their CAHs. Our previous chemical studies on superhydrophobic surfaces also showed that the chemical heterogeneity on the surface strongly influences the final dynamic properties of a superhydrophobic surface [22,[45][46][47].…”

Photosensitised Degradation of Organic Dyes by Visible Light Using Riboflavin Adsorbed on the Surface of TiO2Nanotubes

“…[47][48][49] After anodisation, the TiO 2 NTs were annealed at 400 °C for 3 h in air atmosphere in order to crystallise the oxide nanotubes layer. The nanotube structures were characterised by scanning electron microscopy (SEM) obtained with EVO50-Carl Zeiss equipment.…”

Nano-microstructured, superhydrophobic, and infrared transparent polytetrafluoroethylene/diamond films

“…As in previous works, 14,16 the PTFE layer, with thickness around 120 nm, was deposited by thermal physical vapor deposition at a base pressure of 2 × 10 −6 Torr. A quartz microbalance monitor was used for thickness control.…”