Preparation Of TiO₂Nanocrystals Via Hydrothermal Treatment Of H-Ti Colloidal Suspension And Study On Their Photocatalytic Property

With titanium acid colloid solution for precursors, by changing its reactionconditions to prepare TiO₂nanometer particles, and the nature of the light catalysiswere also studied. The results show that:（1） PH value of TiO₂nanoparticles, size and morphology of crystalline influence.Adjust the HCl reaction precursors of titanate colloid PH value, then the preparationof nanometer TiO₂particles supercritical water. The results show that: by adjustingthe solution of the PH value, can get different size morphology of TiO₂nanoparticles,along with the decrease of the PH value, nanoparticles by anatase phase shift at rutile,finally we get rutile phase of TiO₂nanoparticles.（2） Temperature on the morphology and size nanometer TiO₂influence. In the PH=12when change the reaction temperature, the temperature change range for120oC-230oC, the results show that, with the increase of temperature the morphology ofTiO₂nanoparticles by nanoneedle to granular change, and belongs to a high degree ofcrystallization in sharp titanium ore.（3） Mineralization agent on TiO₂nanoparticles morphology and the influence ofsize. In the PH=12when reactants to add NH₄F, NH₄Cl mineralization agent. Theresults showed that the mineralization agent after, TiO₂nanoparticles is still anatase,but the morphology change, and the two different kinds of mineralization agent on themorphology of nanoparticles affect different.（4） PH=12,7,3samples of the photocatalytic degradation acetaldehyde reaction,through the comparison with commercial do we find in the acetaldehyde reduce PH=3aspects with sample and do quite, but in CO2better than do the relic, show that inthe PH=3conditions of synthesis TiO₂nanoparticles with better the mineralizationactivity.