Self-Cleaning Test of Doped TiO₂-Coated Glass Plates under Solar Exposure

Abstract

Photocatalytic films of TiO2 doped with metal oxides, ZnFe2O4, ZnO, and CuO, were formed on glass plates by the ultraspinning method from Ti(IV) isopropoxide-based sol−gels. To test the self-cleaning properties of TiO2 films on glass, a layer of crystalline fluoranthene, a polycyclic aromatic compound, was placed over the glass by spraying and then exposing it to solar irradiation. The covering of fluoranthene on the 1 wt % metal oxide-doped anatase films was degraded nearly to 100% at 20 h of exposure time. Thus, the coated-glass transparency was recovered totally between 35 and 52 h of exposure time for the doped anatase film, which did not occur with anatase on glass, even after more than 85 h of solar irradiation. For some samples, a correlation was found between the weight losses of the solid compound and the intensity of the Raman vibration at 671 cm−1 during photocatalytic degradation. After 20 h of solar exposure, while the presence of fluoranthene was not detected by Raman spectroscopy, some glass plates presented ultrathin zones of degradation products. Regarding fluoranthene photodegradation and weight loss in the results when the different metal-oxide dopants were compared, a sequential efficiency was observed: ZnFe2O4 > CuO > ZnO.

Photoactive self-cleaning polymer coatings by TiO2 nanoparticle Pickering miniemulsion polymerization

“…Photocatalytic materials have gained extraordinary relevance in the last years due to their potential applications in fields such as photo-induced removal of pollutants from air and water, and self-cleaning and antibacterial materials [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Titanium dioxide (TiO 2 ) is the most widely investigated photocatalyst due to its high photoactivity, low cost, low toxicity and good chemical and thermal stability [16,17].…”

“…Currently, most photocatalytic coatings are prepared by the post-deposition of the catalyst onto a substrate, such as, glass, textiles, metals or polymers [2,[5][6][7][8][9]12]. In the case of photocatalytic waterborne paints, the photocatalyst (TiO 2 ) usually is one of the components of the paint formulation that is blended with the waterborne dispersed polymer (binder) [3,10,11,15].…”

Bioaccumulation, Subacute Toxicity, and Tissue Distribution of Engineered Titanium Dioxide Nanoparticles in Goldfish (Carassius auratus)

“…Nanoparticulate TiO 2 has been utilized as an ultraviolet radiation absorber in transparent sunscreen formulations (Nohynek et al ., 2007) and in specialist photocatalytic coatings for glass (Medina-Valtierra et al ., 2009). The environmental chemistry of TiO 2 NPs has been partly investigated.…”

Design of multi-layer anti-reflection coating for terrestrial solar panel glass

“…Zhang et al [11] reported the nanosized TiO 2 particles coated on the surface of the SiO 2 layer shows excellent surface wettability with ∼1 • contact angle and 99% transmission despite the high refractive index of TiO 2 . Medina-Valtierra et al [12] demonstrated that the doping of metal in TiO 2 enhancing the self-cleaning property of nanostructured thin film. Ebert and Bhusan [13] studied self-cleaning and transparent properties of SiO 2 , ZnO and ITO nanoparticle coatings on glass and plastic substrates (polycarbonate and PMMA) and found superhydrophobic nature θ c (>150 • ) and high transmittance of visible light (T ∼ 90%) in terms of wettability and transmittance.…”