Micro-Patterning of Magnetron Sputtered Titanium Dioxide Coatings and Their Efficiency for Photocatalytic Applications

Abstract

Titanium dioxide thin films were deposited onto sola-lime glass substrates by reactive magnetron sputtering. Fine stainless steel mesh sheets with different aperture sizes were applied as masks over glass substrates to allow the deposition of the coatings with micro-patterned structures and, therefore, enhanced surface area. Non-patterned titania films were deposited for comparison purposes. The titanium dioxide films were post-deposition annealed at 873 K for crystallinity development and then extensively analysed by a number of analytical techniques, including scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDX), optical and stylus profilometry, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy. The photocatalytic activity of non-patterned and micro-patterned titania films was assessed under UV light irradiation by three different methods; namely methylene blue, stearic acid, and oleic acid degradation. The results revealed that the micro-patterned coatings significantly outperformed non-patterned titania in all types of photocatalytic tests, due to their higher values of surface area. Increasing the aperture of the stainless steel mesh resulted in lower photocatalytic activity and lower surface area values, compared to the coatings deposited through a smaller aperture mesh.

Development of a rapid method for assessing the efficacy of antibacterial photocatalytic coatings

“…In this study, the titanium dioxide was not activated by the ambient light due to its large bandgap of 3.20 eV (Ratova et al, 2020), and therefore was unable to reduce the microbial load of either E. coli or K. pneumoniae by a clinically meaningful amount. The bismuth oxide on the other hand, with a much narrower reported bandgap of 2.40 eV (Ratova et al, 2018), was able to reduce the microbial load of E.…”

Antimicrobial Effectiveness of Innovative Photocatalysts: A Review

“…In the field of electrochemical methods, a very interesting green preparation method could be based on sputtering techniques, which, moreover, offer the possibility of developing photocatalysts immobilized on a macroscopic support, thus avoiding the need to separate powder photocatalysts from the treated water [118]. Generally speaking, the sputtering method presents several advantages, such as coating uniformity over large areas, good control of morphological properties in the photocatalytic films, and lack of toxic or hazardous precursors [119].…”

Multi-Walled Carbon Nanotubes Modified NiCo2S4 for the Efficient Photocatalytic Reduction of Hexavalent Chromium

“…Photocatalysis is a promising technology for achieving the one-step removal of Cr(VI) using sunlight due to its efficient, simple, and environmentally friendly features [26][27][28][29]. It has been extensively studied in environmental and energy fields [30][31][32][33]. More and more semiconductor photocatalysts [34] are being investigated and applied for Cr(VI) reduction, hydrogen production, carbon dioxide reduction, and the degradation of organic pollutants such as TiO 2 [35][36][37][38], g-C 3 N 4 [39][40][41], ZnIn 2 S 4 [42,43], NiCo 2 S 4 [43], CuS [44], and BiVO 4 [39,45].…”