Selectivity Of TiO2 Research Articles

Silica nanoparticles impact the permeability of human intestinal barrier

This review provides a background, fundamental and advanced application of titania nanoparticles (TiO2) on the disinfection and killing of cancer cell through photocatalytic chemistry. It starts with the characteristic properties focused on the surface, light sensitivity, crystallinity and toxicology of TiO2 as a photocatalyst. Consequently, outline and design of photocatalytic reactor has been figured out based on the target organisms, including bacteria, viruses, fungi and cancer cells. Despite a large number of studies undertaken, limited selectivity and efficacy of TiO2 photocatalyst are still widely accepted problems. An ideal TiO2 photocatalyst should have the combined properties of highly stable reactive oxygen species yield and a greater degree of selectivity towards cancerous cell without damaging the healthy tissues. Hybridization of TiO2 with metal, metal oxide and carbon nano materials significantly improved both of stability and selectivity of TiO2, whilst maintaining its high Photodynamic reactivity.

Recent developments on titania nanoparticle as photocatalytic cancer cells treatment

This review provides a background, fundamental and advanced application of titania nanoparticles (TiO2) on the disinfection and killing of cancer cell through photocatalytic chemistry. It starts with the characteristic properties focused on the surface, light sensitivity, crystallinity and toxicology of TiO2 as a photocatalyst. Consequently, outline and design of photocatalytic reactor has been figured out based on the target organisms, including bacteria, viruses, fungi and cancer cells. Despite a large number of studies undertaken, limited selectivity and efficacy of TiO2 photocatalyst are still widely accepted problems. An ideal TiO2 photocatalyst should have the combined properties of highly stable reactive oxygen species yield and a greater degree of selectivity towards cancerous cell without damaging the healthy tissues. Hybridization of TiO2 with metal, metal oxide and carbon nano materials significantly improved both of stability and selectivity of TiO2, whilst maintaining its high Photodynamic reactivity.

Catalytic Partial Oxidation of Methanol and Methyl Mercaptan: Studies on the Selectivity of TiO2 and CeO2 Supported V2O5 Catalysts

Catalyst samples based on vanadium, cerium and titanium oxides were prepared using sol–gel method and wet impregnation. Several analytical techniques were used to characterize catalysts. The best activity and selectivity in the partial oxidation of methanol and methyl mercaptan were observed for the catalyst sample with the composition of 3 % V2O5/Ti0.1–Ce0.9O2.

Effect of Dry Etching of TiO2 Thin Films Using Inductively Coupled Plasma

In this study, the effect of the dry etching of titanium dioxide (TiO2) thin films was investigated with addition of O2 to BCl3/Ar plasma. The maximum etch rate of TiO2 thin films and the selectivity of TiO2 to SiO2 were 100 nm/min and 1.07 in O2/BCl3/Ar (= 3:4:16 sccm) plasma, respectively. In addition, the etch rate and selectivity were measured as functions of the etching parameters, such as the gas mixing ratio, RF power, DC-bias voltage, and process pressure. The chemical state on the etched surface of TiO2 thin films were investigated by the x-ray photoelectron spectroscopy. To determine the re-deposition and reorganization of residues on the surface, the surface morphology and roughness of TiO2 thin films were examined by the atomic force microscopy.

Eco-friendly TiO2–AC Photocatalyst for the Selective Photooxidation of 4-Chlorophenol

The influence of surface pH of activated carbon on selectivity of TiO2 during the photooxidation of 4-chlorophenol on UV-irradiation was studied. Chlorine substitution by p-hydroxylation yielding hydroquinone in equilibrium with benzoquinone and o-hydroxylation to 4-chlorocathecol were detected as the main intermediates in the photooxidation of 4CP. Changes in surface pH of carbons from basic to closely neutral induce a remarkably increase in the production of 4-chlorocatechol by a factor of 22 on TiO2–AC in comparison of TiO2 alone. A mechanism of interaction between both solids is proposed to explain changes both in photoactivity and photoselectivity of TiO2. In conclusion, results showed that TiO2–AC can be used as an alternative green photocatalyst in organic synthesis.

Acidic Property and Catalytic Activity of TiO2·ZnO

Abstract A new type of mixed metal oxide TiO2·ZnO was prepared by either heterogeneous or homogeneous co-precipitation and the acidic property was measured by n-butylamine titration and by observation of infrared spectra of adsorbed pyridine. It was found that TiO2·ZnO containing about 7 or 57% of ZnO shows a very large acid amount of 0.5–0.9 mmol/g and a fairly high acid strength of H0≤−3, the acid sites being both Brönsted and Lewis type and the acid sites of high strength created by heterogeneous precipitation. The catalytic activity and selectivity of TiO2·ZnO were found very high for the hydration reaction of ethylene. The catalyst was active also for the alkylation of phenol by methanol and gave only monoalkylated products.