Modular UV Curing Sol-Gel Coating for Invisible, Levelling and Easy to Clean Multi-Layer Systems.

Current methods for the hardening step of functional coatings over different materials imply the use of high temperatures, high energy consumption or long periods of time, which have repercussions on the speed and cost of the product. We report here a simple and low-cost methodology for the functionalization of low-cost stainless steel, which is modular, depending on the functionality pursued: a levelling layer for smoothing the surface of the material, an "easy to clean" property, or both of them. This research is based on sol-gel coatings cured under UV light without requiring high thermal hardening processes, making it applicable to plastics and other sensible materials and possessing high chemical and thermal stability.

Mechanical Performance of AlCrSiN and AlTiSiN Coatings on Inconel and Steel Substrates after Thermal Treatments.

The objective of this study was to explore the mechanical properties of AlCrSiN and AlTiSiN coatings deposited on Inconel and steel substrates after thermal treatments of 500 °C and 800 °C. Nanoindentation was used to measure the hardness and elastic modulus of the coatings, and microindentation was used for observing the contact damage with Hertzian contact loadings. Microscratch and Mercedes tests were used to evaluate the adhesive strength between coating and substrate with both progressive and static loads, respectively.

Antibacterial Activity of Photocatalytic Metal Oxide Thin Films Deposited by Layer-by-Layer Self-Assembly.

This paper reports the use of the Layer-by-Layer self-assembly (LbL) as an efficient technique for the fabrication of thin-films with antibacterial activity. The LbL coatings are composed of a positive polyelectrolyte such as Poly(allylamine hydrochloride) (PAH) and an anionic polyelectrolyte such as Poly(sodium 4-styrene sulfonate) solution (PSS). In addition, these polyelectrolytes can be also used as an adequate encapsulating agent of specific metal oxide precursors such as titanium dioxide (TiO₂) and iron oxide (Fe₂O₃) nanoparticles, making possible the fabrication of hybrid thin films composed of organic polymeric chains related to the polyelectrolytes and inorganic structure associated to the metal oxide nanoparticles.

Quasi-one-dimensional K-O chain in PTCDA thin films: evidence from first-principles calculations.

Using density functional theory calculations we have found that K atoms in a PTCDA (3,4:9,10-perylenetetracarboxylic dianhydride) crystal form a quasi-one-dimensional (1D) K-O chain interacting with carboxylic oxygen of the terminal anhydride groups of PTCDA. The K-K distance in the chain (3.72 Angstrom) is commensurate to the periodicity of the organic semiconductor.