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This work reports a structure and photocatalytic activity of nanoporous titania (TiO2) thin films by an anodizing approach. Xray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM) studies showed that tetragonal anatase was the main phase in the thin films that consisted of countless disordered nanopores in the order of 10 to 15 nm. In the photocatalytic degradation of methylene blue, the titania thin films showed a good photocatalytic activity. 82.2 % methylene blue could be photodegraded by titania thin films with UV radiation. XPS results indicate that during the degradation of methylene blue, some Ti3+ may be partially oxidized to Ti4+ in the TiO2 films and the surface hydroxyls directly participate in the reaction. Our nanoporous titania thin films is commensurable to Degussa-25 TiO2 powders because the latter requires filtration in each treatment; it is also much superior to the direct photolysis approach with respect to photoactivity.

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Mesoporous silica materials (SBA-15) doped with calcium (Ca) at 1, 3 and 5% w/w were synthesized in order to immobilize candida rugosa lipase (CRL), through the adsorption method. It was found that calcium (Ca) is present as CaO, highly dispersed on the surface of SBA-15, the specific area of SBA-15 decreases on incrementing CaO content. The environmental pH influences the adsorption of CRL due to the polarization of positive charges below the isoelectric point (IEP) whereas the Ca-SBA-15 materials present negative charges. The adsorption model proposed for CRL is about the accessible surface of the material, as this has a size of 7 nm and the Ca-SBA-15 present pores at an interval of 3 nm.