Papers by Keyword: Titanium Dioxide Coating

Abstract: In this paper, Mn²⁺ doped ZnS (ZnS:Mn) nanoparticles were prepared by co-precipitation method. And then different thickness of TiO₂ and SiO₂ inorganic shell were coated on prepared ZnS:Mn through the hydrolysis reaction of tetrabutyl titanate (TBOT) and tetraethyl orthosilicate (TEOS). ZnS:Mn crystal and core/shell structure were described by X-ray diffraction (XRD) and scanning electron microscope (SEM). Optical property of all ZnS:Mn/XO₂ (X=Ti, Si) nanoparticles were investigated by photoluminescence (PL) spectrometer. The effect of Mn²⁺ concentration and XO₂ (X=Ti, Si) shell thickness on luminescence intensity of ZnS:Mn/XO₂ was studied. The results showed that with TiO₂ and SiO₂ shell thickening, Mn²⁺ emission of ZnS:Mn/XO₂ samples increased first and then decreased. When the thickness of inorganic shell (molar ratio of shell and core amount) reached to 0.5 (TiO₂) and 1.0 (SiO₂), the optimal luminescence intensity was obtained. The emission of ZnS:Mn/TiO₂ and ZnS:Mn/SiO₂ was 2.0 and 1.5 times more in intensity than that of uncoated ZnS: Mn, respectively.

Abstract: Due to excellent photocatalytic and optical properties of titanium dioxide (TiO2), it has been applied in several products such as food packaging plastics, materials for vehicles or for buildings and sunscreen-protecting cosmetics. In this present work, the synthesized as well as commercial TiO2 was coated onto a household curtain fabric for anti-microbial and ultraviolet (UV) shielding functions. The coating was performed by inducing the deposition of TiO2 layer from the Ti precursor onto the fabric surface pre-treated with silane adhesive agent so as to improve the adhesion. Ag nanoparticles were also incorporated in some samples to further improve the antibacterial function. Anti-bacterial activities of the coated fabric were evaluated by standard qualitative test (the Kirby-Bauer test (AATCC 147)). Efficiency for UV shielding was evaluated by measuring a UV-Vis reflection of the coated fabrics both before and after subjecting to several washing cycles. The result showed that the TiO2-coated fabrics developed had potential as antibacterial and UV shielding for the curtain industry.

Abstract: Adhesion between TiO2 coatings and the fabrics was improved by using a silane adhesive agent. To investigate a suitable method of applying adhesive agent, two different coating methods were conducted. The silane was either mixed with Ti precursor for fabric dipping, or coated onto the fabrics before dipping them in a Ti precursor. The effect of Ti precursor, sol and colloid, on coating morphology was also studied. It was found that continuous coating with no cracking was obtained when the fabrics were pre-treated with the silane. The TiO2 coatings had good adhesion, regardless of the method of applying the adhesive agent. Thick, cracked coatings were obtained from Ti colloid precursor while continuous coating was obtained from the Ti sol precursor.