聚丙烯腈/醋酸纤维素/TiO2复合纳米纤维膜的制备及其光催化降解性能

为研究碱改性前后复合纳米纤维膜的光催化降解性能,首先利用静电纺丝技术制备聚丙烯腈/醋酸纤维素/二氧化钛(PAN/CA/TiO₂)复合纳米纤维膜,依次用0.05、0.10 mol/L的氢氧化钠溶液对其进行碱处理,制得聚丙烯腈/再生纤维素/二氧化钛(PAN/RC/TiO₂)复合纳米纤维膜,并应用于染料废水处理。借助扫描电子显微镜、傅里叶红外光谱仪及接触角测量仪等手段表征了复合纳米纤维膜的结构与亲水性;同时研究了复合纳米纤维膜的力学与光催化降解性能。结果表明:经碱处理后,复合纳米纤维膜的静态接触角由125.30°减小到10.20°,亲水性能得到很大的改善;PAN/RC/TiO₂复合纳米纤维膜对亚甲基蓝(MB)溶液的降解率达到91.2%,而空白对照样对MB溶液的降解率仅为10.1%,且重复使用3次后,复合纳米纤维膜对MB溶液的降解率仍达74.7%。

Preparation of polyacrylonitrile/cellulose acetate/TiO2 composite nanofiber membrane and its photocatalytic degradation performance

In order to investigate the photocatalytic degradation of composite nanofiber membrane before and after alkali modification, the polyacrylonitrile/cellulose acetate/nano-titanium dioxide (PAN/CA/TiO₂) composite nanofibers membrane were first prepared using the electrospinning technology, which was then alkaline treated with 0.05 and 0.10 mol/L NaOH solution respectively to achieve polyacrylonitrile/regenerated cellulose (PAN/RC/TiO₂) composite nanofiber membranes. Scanning electron microscopy observation, Fourier transform infrared spectroscopy analysis and static contact angle measurement were used to characterize the mechanical and photocatalytic degradation of the composite nanofiber membrane. The results show that after the alkali treatment, the static contact angle of the composite nanofiber membrane are reduced from 125.3°to 10.2°, the hydrophilic property is greatly improved. The degradation rate of PAN/RC/TiO₂ composite nanofiber membrane to MB solution reaches 91.2%, while the degradation rate of blank solution to MB solution is only 10.1%. After 3 repeated uses, the degradation rate caused by the MB solution still reaches 74.7%.