TiO₂ based nanopowder coatings over stainless steel plates for UV‐C photocatalytic degradation of methylene blue

Abstract

Immobilizing the photocatalyst in a water treatment process design is essential; however, the immobilization method may affect the photoactivity of the photocatalyst. In this work, photocatalyst powders were successfully coated on 316 L stainless steel plates by a novel brush coating method. Three combinations of photocatalyst mixtures (pure TiO 2 anatase, anatase doped with WO 3 , or TiO 2 rutile) were and annealed at different temperatures between 460-540 C. The~10 μm thick coatings demonstrated full plate coverage and strong adhesion and adequate durability. Surface roughness increased with annealing temperature. The doping and annealing process enabled band gap reduction to the visible light spectrum for all coatings, with the smallest band gap being 2.48 eV (1 eV = 1.6 × 10 −19 J). Subsequent methylene blue degradation tests under UV-C showed that the coatings annealed in 460 C exhibited the best performance and with the highest degradation rate constant of 5.59 hours −1 . K E Y W O R D Sadvanced oxidation process, annealing, band gap, photocatalyst coatings, roughness

Experimental methods in chemical engineering: Atomic force microscopy − AFM

“…Eng .) mention AFM but are excluded in the search; the research described in these articles concerns topics as varied as grafting chitosan onto cotton gauze to adsorb chromium ions from water, [ 45 ] reducing the colour and turbidity of textile waste water with graphene oxide, [ 46 ] coating stainless steel plates with TiO 2 to photocatalytically degrade methylene blue, [ 47 ] and conductive protein fibres. [ 48 ] The journal published eight articles that refer to AFM in 2019, including the application of lignin nanoparticles for composites, UV absorbents and antioxidant formulations, [ 49 ] and a tutorial review on contact angle from this series, [ 50 ] but only one was in the WoS bibliometric search.…”

Analysis of the physical and microbiocidal characteristics of an emerging and innovative UV disinfection technology

“…Finally, our study does not take into account the possible effects of the chip on photocatalytic materials, such as coatings with TiO 2 . These photoreactive materials are widely used for environmental sanitation (eg, water cleaning and air purification) and energy harvesting applications (eg, water splitting for hydrogen generation) due to their low cost, chemical inertness, non-toxicity, high photocatalytic activity and recyclability 20 21. Although the interaction between biocide coatings and the chip could provide further information for disinfection applications, our study aimed to investigate and describe the main characteristics of this emerging chip technology by matching it with mature LED technology through an experiment under controlled conditions.…”

TiO2 Nanocoatings on Natural Fibers by DC Reactive Magnetron Sputtering

“…Therefore, several attempts have been already used to immobilize TiO 2 on different supporting materials [8] and shapes. From these, glass substrates [9,10], glass spheres [11], fiberglass [12], activated carbon, zeolite, and ceramics [13] stainless steel [14] and polyamide fibers [15], can be emphasized. Moreover, photocatalytic fiber is an emerging solution to immobilize catalyst powders [16,17].…”