Al掺杂TiO_2的制备及酸化处理对其光催化活性的影响

锐钛矿相TiO2的光催化活性高于金红石相。采用化学溶液分解法制备了Al掺杂锐钛矿TiO2,并用硝酸对其进行酸化处理。利用TG-DTA、XRD、FTIR、BET和UV-vis等手段对样品进行了表征,通过对甲基橙的降解分析了酸化处理对Al掺杂TiO2光催化活性的影响。结果表明:掺杂Al能有效抑制TiO2由锐钛矿向金红石转变。酸化处理因能增大Al掺杂TiO2的比表面积而使其光催化活性提高。Al/Ti掺杂比为1∶4的样品在酸化处理后具有的光催化活性最高,60min后对甲基橙的降解达到100%。

Preparation of Al-doping TiO2 and effect of acid treatment on its photocatalytic activity

 Anatase phase has a far higher photocatalytic activity than the rutile phase. Al doped TiO₂ photocatalysts were prepared by a chemical solution decomposition method and treated with concentrated nitric acid. The samples were characterized by TG-DTA, XRD, FTIR, BET and UV-Vis, and the effects of acid treatment on the photocatalytic activities of the Al doped TiO₂ samples were analyzed by degradation of methyl orange. The results suggested that Al-doping could effectively inhibit the phase transformation from anatase to rutile. The specific surface area and photocatalytic activity of Al doped TiO2 were increased by acid treatment. The Al doped TiO₂ (Al∶ Ti=1∶ 4) by acid treatment delivered the highest photocatalytic activity, and the degradation ratio of methyl orange was 100％ after 60 min.