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运用溶胶-凝胶及低温水热法合成纳米TiO2/碳纳米管复合催化剂,以甲基橙为目标降解物考察复合物的光催化活性.运用X光衍射、透射电镜、Brunauer-Emmett-Teller低温氮气吸附、差热-热重分析及紫外-可见漫反射吸收光谱等表征催化剂.结果表明,与单纯纳米TiO2相比,溶胶-凝胶法制备的复合催化剂的光催化活性显著提高,实验条件下复合的碳纳米管最适含量为3%(碳纳米管/TiO2,重量百分比),复合催化剂经在缓和氧化气氛中焙烧处理可在保持碳纳米管热稳定前提下获得纳米TiO2的充分晶化.观察到了低温水热合成的复合催化剂的甲基橙降解活性的进一步提升,复合催化剂中纳米TiO2在碳纳米管表面分散均匀,TiO2和碳纳米管组分间的紧密和充分键合及低温水热条件下催化剂的大比表面积、超细粒径以及碳纳米管的热稳定等有利于复合催化剂的光催化活性.进一步地,探讨了复合催化剂中适量碳纳米管组分的光活性促活机制.
The photocatalytic activity of the composite was investigated by sol-gel and low temperature hydrothermal synthesis of nano-TiO2 / carbon nanotubes composite catalyst with methyl orange degradation products.Using X-ray diffraction, transmission electron microscopy, Brunauer-Emmett-Teller low temperature The results showed that the photocatalytic activity of the composite catalyst prepared by sol-gel method was significantly higher than that of pure nano-TiO2. Under the experimental conditions The optimum content of CNTs is 3% (CNTs / TiO2, weight percent). The composite catalyst can be fully crystallized under the premise of maintaining the thermal stability of the CNTs by calcination in a mild oxidizing atmosphere. It was observed that the degradation activity of methyl orange in the composite catalysts prepared by hydrothermal synthesis was further improved. The nano-TiO2 was uniformly dispersed on the surface of the carbon nanotubes in the composite catalyst. The close and sufficient bonding between the TiO2 and the carbon nanotubes and the low temperature hydrothermal Under the conditions of the catalyst surface area, ultrafine particle size and thermal stability of carbon nanotubes and other catalysts are conducive to the photocatalytic activity. Further, to explore the composite Photosensitive Activation Mechanism of Carbon Nanotube Components in Catalyst.