Self‐cleaning, titanium dioxide based, multilayer coating fabricated on polymer and glass surfaces

Abstract

A photocatalytic self-cleaning titanium dioxide (TiO 2 ) coating was prepared as a multilayer coating structure by the spin-coating method. Three substrate materials (two thermoplastics and one ceramic) were used: (1) high-density polyethylene (HDPE), (2) poly(vinyl chloride), and (3) borosilicate glass (BK7). The multilayer structure consisted of a polyurethane protective layer on the substrate, two layers of photocatalytic TiO 2 on the protective layer, and finally immobilized TiO 2 particles bound in a diluted polyurethane dispersion. Photocatalytically active surfaces were achieved by reactive oxygen-plasma surface etching of the fabricated coatings. The structure and properties of the coating surfaces were characterized with scanning electron microscopy and contact-angle measurements. The coatings on HDPE and BK7 were rendered superhydrophilic by an oxygen-plasma treatment. The photocatalytic activity and self-cleaning properties of the prepared surfaces were studied with palmitic acid (model soil), the degradation of which was confirmed by contact-angle measurements and gas chromatography analysis.

Accelerated self-cleaning by Cu promoted semiconductor binary-oxides under low intensity sunlight irradiation

“…Photocatalysis as a useful tool for the self-cleaning of glass, polymer thin films and textile fabric surfaces has recently been reported by Daoud [1][2][3][4], Kiwi [5][6][7][8], Hashimoto/Fujishima et al [9,10], Bahnemann [11][12][13], Radetic [14] and Pakkanen [15]. TiO 2 has been chosen as the standard photocatalyst used in the field of environmental photochemistry due to its stability, effective separation of charges under band-gap irradiation and availability of fairly pure samples.…”

Metal oxide thin films and nanostructures for self-cleaning applications: current status and future prospects

“…So, in those cases a protective layer between polymer and TiO 2 surfaces is essential. Another approach is to use a multilayer film consisting of TiO 2 and polyurethane, which not only serves as protective layer but is also able to bind the TiO 2 particles onto the coating surface [75].…”

Computational Fluid Dynamics (CFD) Modeling of Photochemical Reactors

“…To overcome these drawbacks, immobilized photocatalysts are usually recommended. Photocatalysts could be immobilized on various supports such as glasses (Sabate et al, 1992;Kim et al, 1995;Fernandez et al, 1995;Wang et al, 1998;Piscopo et al, 2000;Sakthivel et al, 2002;Neti et al, 2010), tellerette packings (Mehrvar et al, 2002), silica (Van Grieken et al, 2002;Ding et al, 2001;Xu et al, 1999;Alemany et al, 1997;López-Muñoz et al, 2005;Marugán et al, 2006), polymers (Kasanen et al, 2009), and clays . The analysis and design of photochemical reactors have received increasing interests in chemical engineering recently.…”