Research Of Controllable Synthesis Of TiO₂and F,Ag Co-modified TiO₂

TiO2is widely used as inorganic materials with its nontoxic, stable chemicalproperities, good photocatalytic properties and low cost, etc.In this paper, spherical， rhombus and square TiO2were prepared byhydrothermal method. Spherical TiO2was selected as the modified target, NaF andAgNO3provide F-and Ag particles respectively in TiO2surface modificationprocess. Characterization of samples’ morphology and phase structure were usedby SEM, TEM and XRD. Degradating of methyl orange slution was the methodof studying photocatalytic properties.Spherical TiO2was prepared by titanium (IV) isopropoxide in isopropanol andDETA. The influence of reaction conditions such as titanium precursor, organicsolvents, the amount of DETA, time and temperature, etc. were investigated. TiO2wasanatase by calcining at450℃, reaction conditions have no effect on morphology. Thesize of TiO2prepared by TIP was more uniform, photocatalytic effect was better. Thelonger carbon chain of organic solvents, the easier to form spherical TiO2. Extendingtime and rising temperature was beneficial to forming regular spherical TiO2. Therutile appeared when the calcination temperature was higher than500℃, but theperformance of photocatalytic was lower.Rhombus and square TiO2were prepared by tetrabutyl titanate in formic acid andacetonitrile. By controlling the reaction conditions such as the amount of titanium, theratio of organic solvents, time and temperature, the properties of TiO2wereinvestigated. With the increasing use of titanium source, the production and size ofTiO2were increased.When the content of formic acid higher than acetonitrile and the ratio of formicacid and acetonitrile was3:1, rhombus TiO2was obtained, the remaining ratio werebetter to formate square TiO2. When the content of formic acid lower than acetonitrile,square nano-grain was appeared. Extending time and rising temperature, the shape ofrhombus TiO2was gradually clear. When the temperature elevated, the shape of TiO2changed from rhombus to square. The effect of photocatalytic of rhombus TiO2wasworst.TiO2surface fluorination was conducted in the condition of acidity by NaF. Agnano-particals loaded on the surface of TiO2at the30W UV-light irradition. Theadjunction of Ag nano-particals made the characteristic of spherical disappeared, but the surface fluorination could protect the shape. The photoctalytic performance ofF, Ag comodified TiO2increased at UV-light and simulation solar light irradition.