Preparation of porous carbon-doped TiO2 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 TiO2 (C-TiO2) film to enhance photodegradation efficiency (PE) of gaseous toluene under UV light. PE was affected by thickness of TiO2 film, specific surface area of TiO2, and carbon content doped on TiO2. 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 TiO2 was 230 m2 g−1 and PE with porous TiO2 film was 85–87% in 30 min. The specific surface area of conventional TiO2 was 55 m2 g−1 and PE with normal TiO2 film was 77–79%. To increase higher photodegradation capability of TiO2 under UV light, carbon was doped on TiO2 by sol–gel and combustion method. PE of gaseous toluene with porous carbon-doped TiO2 was 91–94% in 30 min and this was more enhanced by 18–19% than that with conventional TiO2. By-products derived from the photocatalytic oxidation of toluene were mostly amyl formate and ethyl formate, which are non-toxic.