초록 |
Formaldehyde (FA), one of the most harmful volatile organic compounds (VOCs), can be removed by physical adsorption, and photocatalytic oxidation. To decompose FA under atmospheric conditions, photocatalytic oxidation using UV-responsive photocatalyst has been explored. In this work, a series of TiO2-based Aerogels (AE) with controlled chemical and physical properties were synthesized and applied as photocatalysts for FA oxidation using gas-phase fix-bed reactor under UV irradiation. Aerogels were developed using the traditional sol-gel chemistry via doping secondary active metals such as Au, Ag, Fe to tune the band gap energy. The gels were further dried using supercritical CO2 conditions to build 3D interconnected aerogel network. Fe-TiO2-AE shows the band gap energy corresponding to 2.73 eV, suggesting the synergistic effect among the TiO2 and the Fe atoms in the TiO2 lattice. Furthermore, comparison has been made between different types of aerogels by developing monoliths and granules to test the FA degradation efficiency. The results suggest that Fe-TiO2-AE has superior activity with 100% removal efficiency achieved within 60 min. |