掺Fe^(3+)锐钛型TiO_2的制备及其紫外光照下催化降解苯胺

Preparation of Fe^(3+)-Doped Anatase TiO_2 and Its Usage for Photo-catalyzing Degradation of Aniline under UV Light

用水热法制备了掺Fe^(3+)的TiO_2晶体粉末Fe^(3+)/TiO_2,并通过XRD、SEM和TEM等手段对它进行了表征。研究了在紫外光照下Fe^(3+)/TiO_2对苯胺的催化降解效果。分析了苯胺初始浓度、掺Fe^(3+)量、Fe^(3+)/TiO_2用量、光照时间和溶液初始pH值等因素对光催化效率的影响。结果表明:所制备的TiO_2晶体为锐钛矿型即A-TiO_2;晶体粉末由直径约2.5μm的TiO_2微米球组成,各微米球则由八面体型的TiO_2纳米晶体(长度1～1.5μm)通过自组装形成,八面体的三角形边长100～200 nm;在50 mg/L的苯胺溶液中(pH=7),掺杂0.2%(摩尔分数)Fe^(3+)的A-TiO_2粉末用量为0.5 g/L时,室温下紫外光照(λ=365 nm)反应45 min,苯胺降解率达到73.84%。

Fe^3+/ TiO2 crystalline powders were prepared using hydrothermal method and were characterized by XRD, SEM and TEM. The degradation of aniline by using the Fe^3+/ TiO2 crystalline powder under UV light was studied. Effects of the initial concentration of aniline, dosage of Fe^3+ and Fe^3+/ TiO2, illumination time and initial pH value on the degradation of aniline were examined. The experiment results showed that the as.prepared crystalline powders was an anatase crystal ( A.TiO2 ), with crystal powder composed of TiO2 microspheres around 2.5 μm in diameter. The microspheres were formed by self.assembly of octahedral TiO2 nanocrystals (each about 1 ~ 1.5 μm in length) and individual TiO2 octahedron had triangle with side length of 100~200 nm. The degradation rate of aniline was 73.84% after illumination for 45 min at room temperature under UV light (λ= 365 nm), with aniline mass concentration at 50 mg/ L (pH=7), by adding 0.5 g/ L A.TiO2 with Fe3+ concentration of 0.2%(molar fraction).