info:eu-repo/semantics/article
Superhydrophobic brass and bronze meshes based on electrochemical and chemical self-assembly of stearate
Fecha
2019-01Registro en:
Sosa, Mariana Daniela; Lombardo, Gabriel; Rojas, Graciela; Oneto, María Elena; Negri, Ricardo Martin; et al.; Superhydrophobic brass and bronze meshes based on electrochemical and chemical self-assembly of stearate; Elsevier Science; Applied Surface Science; 465; 1-2019; 116-124
0169-4332
CONICET Digital
CONICET
Autor
Sosa, Mariana Daniela
Lombardo, Gabriel
Rojas, Graciela
Oneto, María Elena
Negri, Ricardo Martin
D'accorso, Norma Beatriz
Resumen
The preparation and characterization of superhydrophobic membranes formed on metal meshes (brass and bronze) by coating from stearic acid is presented. The membranes were prepared by two methods: electrolysis and acid etching. The electrolysis process is a one-step method performed by anodizing the mesh in ethanol solutions of stearic acid. Stearic acid concentration, support electrolyte concentration and electrolysis time were systematically varied. Nanostructures, including nanotubes, are induced on the metallic filaments. Analysis by FTIR, XRD, XPS and SEM of surfaces and precipitated material indicate that formed nanostructures are assemblies of metallic stearates on the surface (copper and/or zinc stearates). Superhydrophobicity (contact angles larger than 150°) was only achieved (in the electrolysis method) in cases where the formation of nanotubes was observed. On the other hand, the acid etching process is a two-step method: immersion of the meshes in acid solution of CuCl 2 or FeCl 3 , oxidizing the surface with formation of inorganic salts nano crystals, followed by immersion in stearic acid solution. Organic nanostructures (nanoribbons and/or nanopetals) were observed after the second step. Superhydrophobic surfaces (contact angles between 150 and 170°) were obtained for all the membranes. Both kind of membranes (electrolysis and etching) resulted effective in oil-water separation.