Photo-catalytic TiO 2 was prepared from tetraisopropyl titanate (TPT) in supercritical ethanol. It was found that TPT in supercritical ethanol could be effectively converted into the anatase-form of TiO 2 crystallites...Photo-catalytic TiO 2 was prepared from tetraisopropyl titanate (TPT) in supercritical ethanol. It was found that TPT in supercritical ethanol could be effectively converted into the anatase-form of TiO 2 crystallites. The anatase-form of TiO 2 as a photo-catalyst was evaluated for its adsorptivity and subsequent photo-catalytic activities on formaldehyde, one of the harmful air pollutants in the environment. As a result, the supercritically treated TiO 2 had a high decomposing ability. Under the same condition, the experiment was repeated for 5 times,and photocatalysis of the samples did not decrease. This indicated that the supercritical treatment was effective to prepare photo-catalytic TiO 2, which was feature by stability, longevity and high photo-catalytic decomposition of formaldehyde for environmental cleaning. Meanwhile, unlike conventional chemical reaction, which is complex and time-consuming, supercritical treatment is easy to operate, saving both time and labor.展开更多
Self-organized TiO2 nanotubes were prepared on titanium foils at anodizing voltage of 20V in 0.5% HF solution for 2030min in order to provide a novel high-efficiency photocatalyst. And the resulting TiO2 nanotubes...Self-organized TiO2 nanotubes were prepared on titanium foils at anodizing voltage of 20V in 0.5% HF solution for 2030min in order to provide a novel high-efficiency photocatalyst. And the resulting TiO2 nanotubes, in periodic ring structures around their exteriors, are open on the top, while closed on the bottom. After annealing for 3h in ambient atmosphere, the anatase phase was found, with the increasing content, in the originally amorphous TiO2 nanotubes treated at 350, 400 and 450℃; whereas the rutile phase emerged at 500℃, and the nanotube architecture could be preserved till 550℃. Furthermore, TiO2 nanotubes, fabricated at anodizing voltage of 20V for 20min and then annealed at 400℃, possesses the best photo-catalytic activity, i.e. the decolourisation of methyl orange irradiated for 40min is 99.6%.展开更多
文摘Photo-catalytic TiO 2 was prepared from tetraisopropyl titanate (TPT) in supercritical ethanol. It was found that TPT in supercritical ethanol could be effectively converted into the anatase-form of TiO 2 crystallites. The anatase-form of TiO 2 as a photo-catalyst was evaluated for its adsorptivity and subsequent photo-catalytic activities on formaldehyde, one of the harmful air pollutants in the environment. As a result, the supercritically treated TiO 2 had a high decomposing ability. Under the same condition, the experiment was repeated for 5 times,and photocatalysis of the samples did not decrease. This indicated that the supercritical treatment was effective to prepare photo-catalytic TiO 2, which was feature by stability, longevity and high photo-catalytic decomposition of formaldehyde for environmental cleaning. Meanwhile, unlike conventional chemical reaction, which is complex and time-consuming, supercritical treatment is easy to operate, saving both time and labor.
文摘Self-organized TiO2 nanotubes were prepared on titanium foils at anodizing voltage of 20V in 0.5% HF solution for 2030min in order to provide a novel high-efficiency photocatalyst. And the resulting TiO2 nanotubes, in periodic ring structures around their exteriors, are open on the top, while closed on the bottom. After annealing for 3h in ambient atmosphere, the anatase phase was found, with the increasing content, in the originally amorphous TiO2 nanotubes treated at 350, 400 and 450℃; whereas the rutile phase emerged at 500℃, and the nanotube architecture could be preserved till 550℃. Furthermore, TiO2 nanotubes, fabricated at anodizing voltage of 20V for 20min and then annealed at 400℃, possesses the best photo-catalytic activity, i.e. the decolourisation of methyl orange irradiated for 40min is 99.6%.
