The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol...The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy(TEM), scanning electron microscopy(SEM), infrared spectroscopy(IR) and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.展开更多
The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion...The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion irradiated under UV.The experimental results showed that the immersion method,especially using the nano TiO2 as immersion matrix,greatly enhanced the photocatalytic activity.One fold enhancement in photocatalytic activity was observed in the case of the sample prepared by immersion doping method.This may be attributed to the nano-size effect,the irreversible hole trapper in non-saturated bonding field of Fe3+ and larger lattice strain.展开更多
文摘The template method for preparing nanostructures entails the synthesis of the desired material within the pores of a nanoporous membrane. In this work, TiO2 nanotubules of the anatase form have been synthesized by sol-gel chemical method using porous anodic alumina as the template. Transmission electron microscopy(TEM), scanning electron microscopy(SEM), infrared spectroscopy(IR) and X-ray diffraction were used to investigate the structure and morphology of the TiO2 nanotubules. The results showed that the diameter and length of the obtained nanotubules were determined by the pore size and length of the PAA template. It was founded that through control of immersion time, both tubules and fibrils can be prepared; in addition, the wall thickness of the nanotubules can be varied at will. The result indicated that the sol particles absorbed preferably to the pore walls of the PAA membrane due to the fact that the pore walls were negatively charged and the TiO2 particles were positively charged.
文摘The iron doping titanium dioxide was prepared by sol-gel,step precipitation,co-precipitation and immersion methods,respectively.The photocatalytic activities of these prepared samples were evaluated in X-3B dispersion irradiated under UV.The experimental results showed that the immersion method,especially using the nano TiO2 as immersion matrix,greatly enhanced the photocatalytic activity.One fold enhancement in photocatalytic activity was observed in the case of the sample prepared by immersion doping method.This may be attributed to the nano-size effect,the irreversible hole trapper in non-saturated bonding field of Fe3+ and larger lattice strain.