中文摘要：

加热处理纳米锐钛TiO2使其发生转晶，因而得到一种利用可见光激发的光催化剂，并对此催化剂用x射线衍射，红外吸收，紫外可见吸收等方法进行了表征．用该方法得到的TiO2为催化剂，进行可见光催化降解酸性红B的研究．结果表明，随着加热温度的升高，TiO2转晶比例逐渐增大，温度升到1000℃，全部锐钛型转变成金红石型TiO2，但TiO2在500℃下加热30min催化活性最高，酸性红B的光降解效果明显优于单独使用纳米锐钛型、纳米金红石型TiO2和按照转晶的比率混合的锐钛型和金红石型TiO2．这种显著提高的光催化作用归因于加热所形成的特殊锐钛-金红石界面耦合状态，导致光生电子从金红石相转移到锐钛相，避免了电子-空穴对的复合．

英文摘要：

A kind of novel TiO2 photocatalyst which could be excited by visible lights is obtained by heating nanometer anatase TiO2, which results in phase transformation from anatase phase to rutile phase. The photocatalyst at transition stage is characterized by XRD, IR and UV -vis methods. The test of photocatalytic activity of the heat - treated TiO2 powder is carried out by degradation of acid red B dye in aqueous solution in visible lights irradiation. The results shows that the ratio of phase transformation increases with the ascending heating temperature. As roasting temperature rises up to 1000 ℃, the phase transformation from anatase to ru- ffle finishes. However, the highest photocatalytic activity of heat - treated TiO2 appears at the heating temperature of 500 ℃ for 30 min, the photocatalytic activity is obviously higher than that of original anatase, rutile TiO2 catalysts and mixed crystal TiO2 by phase transformation proportion. The remarkable improvement of photocatalytic activity of heat - treated TiO2 powders at 500 ℃ is mainly illustrated by the special interphase formed between rutile and anatase phases which results in the electron transfer from rutile phase to anatase phase and thus restrains the recombination of photogenerated electron -hole pairs.