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Given the low cost of their components and their demonstrated reliable efficiencies, dye-sensitized techniques based on the titanium dioxide (TiO2) thin films have received much research attention in the past decade. The dSubscript textye/TiO2 thin films were prepared on glass fibers substrate by a dip-coating method combined with a sol-gel process and the photocatalytic of acetone was investigated in this study. The natural botanical dye of Gardenia jasminoides with absorption reflection intensity in 410-460 nm of liquid extraction was used to improve the photo absorbability under illumination of visible light source. Degradation of acetone under 420 nm light illumination was conducted to evaluate the photocatalytic ability of the dye/TiO2 thin films. The SEM images evidence that fibers existed in the dye/nano-TiO2 composites. The dye/TiO2 thin films catalyst prepared in the laboratory shoSubscript textwed photocatalytic performance with the degradation efficiency of 55% under 420 nm. A few percentages increase in removal efficiency when compared with the dye less TiO2 thin films.

Stainless steel (SS) 304 sieves are characterized by their high permeability and high surface area, which can be flexibly used in different photochemical reactor designs. In this work, low pressure plasma cleaning methods in Ar or N2 atmospheres were adopted to clean the surfaces of sieves prior to the deposition of TiO2 coatings by sol–gel and dipping methods. Heat treating at 200 °C was employed after the deposition process. The surface morphologies, crystalline structures and chemical compositions of TiO2 coated sieves were further analyzed. The antibacterial properties of sieves were also evaluated, using the bioaerosol residual test. It was obvious that all TiO2 coated sieves exhibited adequate bactericidal efficiency, destroying over 98% of bacteria. For TiO2 coated #100 and #300 mesh sieves without plasma cleaning, good TiO2 adhesion and at least 98% bactericidal efficiency were observed. The bactericidal efficiency of sieves also increased with increasing Ti content of coatings. In addition, the surface morphologies and chemical compositions of Ar plasma pre-cleaned and TiO2 coated sieves were unchanged even after being sterilized 5 times, which is very useful in the rapid temperature change environments. It is concluded that the Ar plasma pre-cleaned and TiO2 coated SS 304 sieve is a simple, economic and flexible coating method, which is easy for technical transferring and promising in the application of environmental protection fields.

The Dye-Sensitized TiO2 thin film fabricated by TiO2 nanoparticles is a novel technology with advantage in low cost, little pollution and simple in manufacturing process. The fiber-shaped reacting sites provide enlarged photo-sensing area of the TiO2 thin films. Natural dye of TCPP was applied to improve the photo absorbability in this study. Besides, a novel plasma surface activation technique employed on the thin film showed well performance compared with previous reports by heating methods. The SEM images demonstrate that the nano-TiO2 composites deposited on the fiber substrate. Degradation of acetone under 365 and 420 nm light irradiation were conducted to evaluate the photocatalytic ability of the TiO2 and TCPP/TiO2 thin films. While TiO2 thin films gel catalyst showed good photocatalytic performance with a high degradation efficiency of 99.9%, only about 80% conversion efficiency was achieved by the TCPP/TiO2 thin films reactor under 365 nm light irradiation. Although the TCPP dye on TiO2 nanoparticle shows beneficial reflection intensity in 420 nm, the acetone degradation capability of TiO2 and TCPP/ TiO2 thin films reactor decreased about 30% and 25% respectively compared with the degradation efficiency under 365 nm.

TiO2 thin films obtained by sol-gel and dipping deposition on glass fibers substrates followed by thermal treatment was used in this works. In an attempt to understand the structure and the morphology of TiO2 sol-gel thin films, analysis by X-ray diffraction (XRD) and scanning electron microscopy (SEM) are reported. Degradation of toluene under 365 nm light illumination was conducted to evaluate the photocatalytic ability of the TiO2 thin films. A special design of glass reactor allowed the UV lamp to be located in the center of the reactor. The photocatalyst reactor was then filled with TiO2 thin films/glass fibers substrates to exams the photocatalysis of toluene vapor ranged from 10 to 1,000 ppmv. Toluene depletion was sampled by gas chromatography (GC). The results showed that the photocatalytic performance of the reactor had high toluene depletion efficiency of 99.9% under 20 ppmv, and the efficiency decreased when toluene concentration were 100 and 1,000 ppmv. The improvement of the photocatalytic activity was ascribed to the fibers-based reactor provides a significantly huge surface area of the TiO2 thin films. These results will be useful and assist engineers to design photocatalyst reactors for the VOCs removal.