Photocatalytic activity of TiO2 films preserved under different conditions: The gas-phase photocatalytic degradation reaction of trichloroethylene

The photocatalytic activity of TiO2 films preserved under different conditi ons was investigated in the gas-phase photocatalytic degradation of trichlo roethylene (TCE), The photocatalytic activity of the TiO2 films was found t o depend greatly on the preservation temperature and time. The TiO2 films w ashed with water and then preserved at room temperature exhibited low photo catalytic activity compared with those that were unwashed. When the preserv ation time of the TiO2 films was long, their photocatalytic activity decrea sed, irrespective of the preservation conditions. The catalyst that is deac tivated due to the long preservation time can be regenerated by UV preillum ination. (C) 2000 Academic Press.