针对溶胶凝胶法制备光催化剂过程中颗粒分散不均匀、易团聚的问题,采用SDP( Spinning disk process)联合溶胶凝胶法制备不同焙烧温度的多壁碳纳米管( MWCNTs)-TiO2光催化剂。通过XRD、FTIR、SEM、TEM表征样品的微观结构和形貌,利用UV-vis DRS( Ultraviolet visible diffuse reflectance spectra)表征其可见光响应性,并考察样品在可见光下降解喹啉的性能。结果表明,SDP联合溶胶凝胶法能够以连续流形式制备更微小的、分散更均匀的光催化纳米颗粒(晶粒尺寸约为10 nm)；MWCNTs以光敏化剂的形式使样品具有可见光响应,450℃下焙烧得到的光催化剂MCT3有最强的可见光吸收和最佳的催化活性,反应时间为180 min时,喹啉降解率为86.6%。
MWCNTs-TiO2 photocatalysts were formed within a very thin liquid film generated on a continuous flow spinning disc surface, in which two jets located in the center of the disc were fed with a suspension of HNO3-purified MWCNTs (0. 5 g) in a mixture of tetra-n-butyl titanate (40 mL), ethanol (100 mL) and acetic acid (10 mL), and a solution of ethanol (30 mL), acetic acid (20 mL) and water (8 mL). The collected products were gelled at room temperature for 24 h, dried at 80℃ for 4 h and cal-cined at 350, 400 and 450℃ for 4 h. The samples were characterized by XRD, FT-IR, SEM, TEM and UV-vis DRS. The photocata-lytic properties were evaluated by the degradation of quinoline under visible light irradiation. Results showed that TiO2 nanoparticles of the photocatalyst were smaller (5-10 nm) than when there were no MWCNTs present (10-15 nm), and were well distributed between the MWCNTs. MWCNTs promoted the visible light absorption of the samples. The photocatalyst calcined at 450 ℃ showed the strongest visible light absorption and best catalytic activity, andproduced a quinoline degradation of 86. 6% after 180 min.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%