Preparation of porous carbon-doped TiO 2 film by sol–gel method and its application for the removal of gaseous toluene in the optical fiber reactor

In this paper, we prepared the carbon-doped TiO 2 (C-TiO 2) film to enhance photodegradation efficiency (PE) of gaseous toluene under UV light. PE was affected by thickness of TiO 2 film, specific surface area of TiO 2, and carbon content doped on TiO 2. The highest value of PE was 76% with 3.2-μm-thick film. By adding 0.435 g HPC, the maximum specific surface area of TiO 2 was 230 m 2 g −1 and PE with porous TiO 2 film was 85–87% in 30 min. The specific surface area of conventional TiO 2 was 55 m 2 g −1 and PE with normal TiO 2 film was 77–79%. To increase higher photodegradation capability of TiO 2 under UV light, carbon was doped on TiO 2 by sol–gel and combustion method. PE of gaseous toluene with porous carbon-doped TiO 2 was 91–94% in 30 min and this was more enhanced by 18–19% than that with conventional TiO 2. By-products derived from the photocatalytic oxidation of toluene were mostly amyl formate and ethyl formate, which are non-toxic.