Preparation of TiO2 coatings on PET monolitos for the photocatalytic elimination of trichloroethylene in the gas phase

SÁNCHEZ B.; CORONADO J.; CANDAL R.J.; PORTELA R.; TEJEDOR I.; ANDERSON M.; TOMKINS D.; LEE T.

APPLIED CATALYSIS B-ENVIRONMENTAL

ELSEVIER

Año: 2006 vol. 66 p. 295 - 301

0926-3373

This paper presents the first data on the performance of polyethylene terephthalate (PET) monoliths as photocatalytic support. For this purpose, first a protective layer of SiO2 was also applied to the polymer to prevent oxidation of the substrate, and subsequently the photoactive layer of TiO2 was deposited on PET monoliths using the dip-coating technique. In order to increase adherence of the inorganic coatings, two different synthesis procedures were evaluated. One approach was based on reducing the surface tension of the SiO2 sol using a fluorinated surfactant to increment the PET wettability. The second approach consisted in modifying the PET surface with a layer of the polymer poly(diallyldimethylammonium) chloride (PDDA), which provides a positively charged surface for the fixation of the alkaline SiO2 sol. Both TiO2/SiO2 coated PET monoliths were assayed in a single-pass annular reactor for the destruction of trichloroethylene (TCE). The two coating procedures were compared in terms of homogeneity, durability and photocatalytic activity.