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An investigation on unusual interface properties of unprecedented ternary composites, formed by the inclusion of assorted proportions of B 2 O 3 into TiO 2 /SiO 2 structure, is conducted herein. The influences of B 2 O 3 content and calcination temperature were evaluated. The precursor TiO 2 /SiO 2 material was synthesized via a simple sol-gel procedure that was followed by B 2 O 3 inclusion via maceration and calcination. The materials were fully characterized and their photocatalytic performance to degrade the Indigo Carmine dye investigated. The material prepared with a B/Ti molar ratio of 1 and at calcination temperature of 350 °C (B 1-350 ) showed the best performance, with a superior photocatalytic activity than that of commercial TiO 2 . The presence of B 2 O 3 -TiO 2 -SiO 2 interfaces in the structure of such material was of critical importance in producing a material with these attractive features. Finally, high resolution mass spectrometry monitoring allowed for the characterization of the main degradation products formed under these conditions.

Degussa P-25 TiO2 powder was used as a catalyst in the photocatalytic oxidation of organics. With the objective of promoting a more effective electron-hole separation upon irradiation, the catalyst was modified with small amounts of platinum. Characterisation of the powders was done by X-Ray diffraction and SEM. Chloroform was used as a model molecule and its degradation followed using selective electrodes, with excellent results for the modified titania. Langmuir-Hinselwood kinetic was used to describe the heterogeneous oxidation of chloroform on TiO2, for low solute concentrations.