Fluorinated TiO2 composites were prepared by the sol–gel method. The photocatalytic activities of the composites were evaluated with bromophenol blue (BPB). Composites which contained carbon nanotubes showed the highest photodegradation (98%) of BPB at 20 min as compared to pure TiO2. Photodegradation by-products of BPB such as Br and [SO4]2 ions were monitored with ion chromatography. All catalysts were characterized with microscopic techniques, including transmission electron microscopy and scanning electron microscopy which were both equipped with an energy dispersive X-ray spectrophotometer. The polymorph of TiO2 was verified by the use of Raman spectroscopy and powder X-ray diffraction.