Synthesis by the sol-gel process of visible light sensitive-TiO2 for the degradation of pollutants and microorganisms

To stabilize the TiO2-dye interaction, free metal tetra(4-carboxyphenyl)porphyrin and nickel tetra(4-carboxyphenyl)porphyrin were introduced into the TiO2 matrix by cogelation rather than by grafting. DR and FT-IR spectroscopies were performed to establish the interaction between porphyrins and TiO2. Cristallinity and specific surface area were performed by XRD and nitrogen adsorption-desorption measurements. The photoactivity of doped-TiO2 xerogels was evaluated for p-nitrophenol and Escherichia coli degradation. Under visible light, the samples allowed the degradation of 40% of p-nitrophenol in 6 h and the elimination of 108 CFU/mL of E. coli in 48 h.