In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to thei...In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to their importance broad practical and medical applications. Thermal properties as well as X-ray diffraction analyses were employed to characterize the structure properties of such composite. The obtained results showed variations in the glass transition temperature (Tg), the melting temperature (Tm), shape and area of thermal peaks which were attributed to the different degrees of crystallinity and the existence of interactions between PMMA and TiO2 nanoparticle molecules. The XRD patterns showed sharpening of peaks at different concentrations of nano-TiO2 powder with PMMA. This indicated changes in the crystallinity/amorphosity ratio, and also suggested that the miscibility between the amorphous components of homo- polymers PMMA and nano-TiO2 powder is possible.The results showed that nano-TiO2 powder mix with PMMA can improve the thermal stability of the homo-polymer under investigation, lead- ing to interesting technological applications.展开更多
The transition metal ion doped TiO 2 nanoparticles were prepared with hydrothermal method, and the effects of doping different metal ions on the ability of TiO 2 in photocatalyzing degradation of rhodamine B(RB) were ...The transition metal ion doped TiO 2 nanoparticles were prepared with hydrothermal method, and the effects of doping different metal ions on the ability of TiO 2 in photocatalyzing degradation of rhodamine B(RB) were studied. The results showed that the doping of Fe 3+ , Co 2+ , Ni 2+ and Cr 3+ in TiO 2 nanoparticles made the photocatalytic efficiency of the TiO 2 particles reduce and the higher the initial content of Fe 3+ , the lower the ability of TiO 2 in photocatalyzing the degradation of RB. But the doping of Zn 2+ and Cd 2+ , especially Zn 2+ , made the photocatalytic efficiency of the TiO 2 particles enhance, showing a great increase of the rate constant( k ) and the initial reaction rate( r ini ).展开更多
Nanometer sized Au/TiO\-2 particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2 with light of wavelength (λ)>330 nm. The absorption maximum attributed to the surface plasmon ...Nanometer sized Au/TiO\-2 particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2 with light of wavelength (λ)>330 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 20 nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO\-2 in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.展开更多
文摘In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to their importance broad practical and medical applications. Thermal properties as well as X-ray diffraction analyses were employed to characterize the structure properties of such composite. The obtained results showed variations in the glass transition temperature (Tg), the melting temperature (Tm), shape and area of thermal peaks which were attributed to the different degrees of crystallinity and the existence of interactions between PMMA and TiO2 nanoparticle molecules. The XRD patterns showed sharpening of peaks at different concentrations of nano-TiO2 powder with PMMA. This indicated changes in the crystallinity/amorphosity ratio, and also suggested that the miscibility between the amorphous components of homo- polymers PMMA and nano-TiO2 powder is possible.The results showed that nano-TiO2 powder mix with PMMA can improve the thermal stability of the homo-polymer under investigation, lead- ing to interesting technological applications.
文摘The transition metal ion doped TiO 2 nanoparticles were prepared with hydrothermal method, and the effects of doping different metal ions on the ability of TiO 2 in photocatalyzing degradation of rhodamine B(RB) were studied. The results showed that the doping of Fe 3+ , Co 2+ , Ni 2+ and Cr 3+ in TiO 2 nanoparticles made the photocatalytic efficiency of the TiO 2 particles reduce and the higher the initial content of Fe 3+ , the lower the ability of TiO 2 in photocatalyzing the degradation of RB. But the doping of Zn 2+ and Cd 2+ , especially Zn 2+ , made the photocatalytic efficiency of the TiO 2 particles enhance, showing a great increase of the rate constant( k ) and the initial reaction rate( r ini ).
文摘Nanometer sized Au/TiO\-2 particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2 with light of wavelength (λ)>330 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 20 nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO\-2 in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.
