The photocatalytic activity of titanium oxide supported on ZSMS, zeolite A, silica, and alumina was investigated using the photooxidation of 4-chlorophenol and ...
J. Phys. Chem. 1995, 99, 11501-11507
11501
Enhanced Photoactivity of a Titanium(1V) Oxide Supported on ZSMS and Zeolite A at Low Coverage Yiming Xu and Cooper H. Langford* Department of Chemistry, University of Calgary, 2500 University Drive N. W., Calgary, Alberta l 2 N lN4, Canada Received: October 17, 1994; In Final Form: May 10, 1995@
The photocatalytic activity of titanium oxide supported on ZSMS, zeolite A, silica, and alumina was investigated using the photooxidation of 4-chlorophenol and acetophenone as test reactions. It was found that the photocatalytic activity of titanium oxide on ZSMS and zeolite A was higher than that of a Ti02 powder prepared in parallel or Ti02 formed on silica and alumina, respectively. Ti02/ZSMS, which showed the highest photoactivity at low Ti content, was observed to have large adsorptivity for the organic substrates. It was also found that a decrease in zeolite crystallinity decreased the photoactivity of TiOz/zeolite A. These observations suggest that adsorption and zeolite structure are factors which may be responsible for enhancement of photocatalytic activity of supported Ti02. The sample characterization by XRD, BET, FTIR, and Raman spectroscopy indicates that titanium oxide is formed as small particles of anatase on all the supports and that there are also noncrystalline titanium oxide species formed on zeolite supports. Maximal photocatalytic activity is observed at low (