【摘要】 采用酸性溶胶法合成TiO2 膨润土纳米复合光催化剂 ,并研究其光催化降解阳离子偶氮染料 .X射线衍射 (XRD)分析表明 ,TiO2 膨润土纳米复合物的d0 0 1衍射角为 9 0 6° .该复合催化剂具有较高的光催化降解有机污染物的活性 ,随着光照时间的延长 ,阳离子红GTL的特征峰 490 5nm强度逐渐减弱 ,最后它的特征峰可彻底消失 ,GTL的偶氮键是最活跃的化学键 ,它易于被氧化断键 .该复合催化剂的催化活性受溶液的pH影响较大 ,在中性和碱性条件下其光催化活性更强 .适量的过氧化氢可以加速光催化氧化反应 ,但过量的H2 O2 却抑制了羟基自由基的生成 ,从而使H2 O2 的利用效率下降 ,在本实验条件下其最佳用量是 6mmol L .更多还原

【Abstract】 Titanium dioxide/bentonite nanocomposite prepared by acid-catalyzed sol method was used as a photocatalyst in the reaction of cationic azo dye decomposition in water. The incorporation of TiO 2 was confirmed by powder X-ray diffraction (XRD). The nanocomposite photocatalysts have high photocatalytic activity. The intensity of the 490.5*!nm absorption peak corresponding to the cationic red GTL decreased rapidly during the photolysis process. It also indicated that the —N N— bond of GTL was the most active site for oxidative attack. The photo-activity was greatly dependent on the solution pH, and it was more effective for GTL to be degraded under alkaline and neutral conditions.Results also indicated that the proper addition of hydrogen peroxide could improve the decolorization rate, but excess hydrogen peroxide could quench the formation of ·OH. The proper dose of H 2O 2 was 6 mmol/L.更多还原