ABSTRACT
We report the details of our success in conferring photocatalytic self-cleaning properties on keratin fibers using modified sol-gel colloids. To the best of our knowledge, we studied for the first time the crucial effect of the concentration of titanium dioxide precursor on colloid composition, properties, and biocompatibility in an attempt to enhance the properties and application of anatase titanium dioxide colloid to keratins. The transparency, the particle size distribution, and the crystallinity of synthesized colloids were systematically investigated. The compatibility of the colloids and keratin substrates is thoroughly compared and discussed. The insights presented contribute to the further understanding of the structure-property-use relationship of titanium dioxide in biomaterial applications.
Subject(s)
Keratins/chemistry , Titanium/chemistry , Biocompatible Materials , Catalysis , Colloids/chemistry , Particle Size , Photochemical ProcessesABSTRACT
Anatase nanocrystals were successfully synthesized and deposited on protein keratin-type wool fibers with good compatibility and significant photocatalytic self-cleaning activity using the sol-gel process. Due to the low chemical resistance and liability to photo-degradation of protein materials, the effect of the acid catalyst used in the sol synthesis was studied. The sols were prepared using oxidizing and non-oxidizing catalysts, nitric acid and hydrochloric acid, respectively, for the hydrolysis and condensation reactions of the titanium dioxide precursor. The size distribution and crystallinity of the sols were characterized by X-ray diffraction spectroscopy and photon correlation spectroscopy. The compatibility of sol formulations and wool is thoroughly compared and discussed by analyzing fibers photo-degradation, surface morphology and self-cleaning properties including stain degradation and colorant decomposition. The UV absorption and mechanical properties of wool fibers before and after coating are also discussed.
Subject(s)
Biocompatible Materials/chemistry , Keratins/chemistry , Photochemistry/methods , Catalysis , Feasibility Studies , Hydrochloric Acid/chemistry , Hydrolysis , Nanostructures/chemistry , Nanotechnology/methods , Oxygen/chemistry , Phase Transition , Stress, Mechanical , Titanium/chemistry , Ultraviolet Rays , X-Ray DiffractionABSTRACT
In this article, ferrous ferric oxide and Fe(3)O(4)-doped titanium dioxide have been synthesized by a low-temperature sol-gel process. In particular, we studied the structural characteristics of newly synthesized photosensitive catalysts and their photocatalytic abilities under UV and visible light irradiation. The elemental composition, surface area, crystallinity, and morphology of synthesized catalysts were characterized by Fourier transformation infrared spectrophotometry, X-ray photoelectron spectroscopy, X-ray diffraction, and transmission electron microscopy with selected area electron diffraction and energy-dispersive X-ray spectroscopy. The UV-vis transmission, zeta-potential, and cytotoxicity of the synthesized catalysts are also discussed. It is anticipated that the synthesized ferrous ferric oxide arrays a prospective photocatalyst substitute for titanium dioxide.
ABSTRACT
In this article, we report an optimization study of a photocatalytic self-cleaning sol-gel formulation. In particular we studied the effect of formulation preparation time on the formation of anatase titanium dioxide sol and its compatibility to protein keratin-type wool fibers. The sols were formed by a low temperature sol-gel process. The nucleated anatase was characterized by UV-vis transmission, particle size distribution, X-ray diffraction, and transmission electron microscopy. The compatibility between the formulations and wool fibers is evaluated by field-emission scanning electron microscopy, UV transmission, and mechanical properties. The photocatalytic self-cleaning activity of coated fibers and its reproducibility are also discussed.
