SBA-16, a kind of highly ordered mesoporous silica, was synthesized via a sol–gel method used as the supporter of TiO₂ nanoparticles. With variation of Si/Ti molar ratios at 5.6, 1.4 and 0.7, SBA-16/TiO₂ nanocomposites were prepared. In this study, pristine TiO₂ was also synthesized as a control sample. Prior use, as-synthesized powders were calcined at 500 °C for 4 h. Physicochemical properties of the calcined powders were characterized by using various techniques. Degradation studies of a commercial paraquat (PQ) herbicide, having blue color from addition of the unknown dye, were performed using the SBA-16/TiO₂ nanocomposites compared with the SBA-16 support and the pristine TiO₂. Experimental results showed that the blue colors of the solutions were faded very quickly within 30 min when tested with SBA-16 and 5.6 SBA-16/TiO₂ in dark conditions. The solutions were completely decolorized when the UV light was on for all composites and the pristine TiO₂. The degradation of the dye was mainly depended on the adsorption process on SBA-16 surfaces. Photodegradation of PQ in the solutions was started by the nanocomposites and TiO₂ tested under UV illumination conditions. The dye was completely degraded and the concentrations of PQ in the prepared solutions were reduced and reached to the maximum reduction at 70% within 24 h by 1.4 SBA-16/TiO₂. Kinetic mechanisms for the differences of degradation characteristics by the catalysts under light-on and off conditions were studied, discussed and modelled.

SBA-16 是一种高度有序的介孔二氧化硅，通过溶胶-凝胶法合成，用作 TiO ₂纳米颗粒的载体。随着Si/Ti摩尔比在5.6、1.4和0.7的变化，制备了SBA-16/TiO ₂纳米复合材料。在本研究中，还合成了原始 TiO ₂作为对照样品。在使用之前，合成的粉末在 500 °C 下煅烧 4 小时。通过使用各种技术表征煅烧粉末的物理化学性质。与 SBA-16 载体和原始 TiO ₂相比，使用 SBA-16/TiO ₂纳米复合材料对商业百草枯 (PQ) 除草剂进行降解研究，该除草剂因添加未知染料而呈蓝色. 实验结果表明，在黑暗条件下用 SBA-16 和 5.6 SBA-16/TiO ₂测试时，溶液的蓝色在 30 分钟内迅速褪色。当对所有复合材料和原始 TiO ₂开启紫外光时，溶液完全脱色。染料的降解主要取决于 SBA-16 表面的吸附过程。溶液中 PQ 的光降解是由在紫外线照射条件下测试的纳米复合材料和 TiO ₂开始的。1.4 SBA-16/TiO ₂染料完全降解，制备溶液中PQ的浓度降低，24小时内最大降低70%. 研究、讨论和建模了催化剂在开灯和关灯条件下降解特性差异的动力学机制。