A comparison between bulk and supported TiO2 photocatalysts in the degradation of formic acid

The photocatalytic activity of bulk and supported TiO2 catalysts were tested using formic acid as a probe molecule. The supported catalysts tested were prepared by impregnation using aluminum oxide (Al2O3) as the support and the bulk catalysts by precipitation, both in sol-gel systems. For purposes of comparison, a photocatalyst supplied by DEGUSSA (P25) was also tested. The photolysis rate was found to be less significant than the photocatalytic rate. The Langmuir-Hinshelwood model was adopted and its constants were estimated and used to compare the various catalysts. The supported catalysts ...