Photocatalytic decomposition of gaseous HCHO over a titanium dioxide film formed on a hydrophobic PET sheet

Abstract

AbstractBACKGROUND: The authors (Chem Eng J 148, 234 (2009)) previously demonstrated the excellent performance of a photocatalytic reactor with a parallel array of nine light sources. To enhance the possibility of practical application of this reactor, the present work explores the use of a PET (polyethylene terephthalate) sheet as a new cheap material to support TiO2, as an alternative to glass tubes. A method of coating the hydrophobic PET sheet with a TiO2 film using an aqueous coating solution is investigated and the performance of the TiO2‐PET sheet prepared evaluated.RESULTS: The affinity of the coating solution for the PET sheet is greatly enhanced by addition of 0.01% (w/w) nonionic surfactant (polyoxyethylene lauryl ether). A relatively uniform thin TiO2 film is formed on the entire surface of the PET sheet by applying the coating solution to the PET sheet and drying it at 100 °C. Decomposition experiments of gaseous HCHO indicate that the photocatalytic activity, although initially low, is increased with repeated use. This is because surfactant molecules added interfere initially with the decomposition of HCHO. After their decomposition, the TiO2–PET sheet decomposes HCHO at almost the same rate as does the TiO2–glass tube.CONCLUSION: The photocatalytic reactor with a parallel array of nine light sources can utilize a PET sheet as TiO2 support with a reduction in material cost. Copyright © 2011 Society of Chemical Industry