Improved photocatalytic oxidation of arsenic (III) with WO/TiO nanomaterials synthesized by the sol-gel method.

Photocatalytic oxidation of arsenite (As(III)) to arsenate (As(V)) was studied in aqueous solution using a series of WO/TiO semiconductors readily synthesized through sol-gel method with WO content in the range of 1-5 wt%. The resulting materials showed enhanced photocatalytic activity towards As(III) photo-oxidation compared to their individual counterparts under UV radiation. The amount of As(III) and As(V) species in the irradiated solution was determined using the molybdenum blue method.

Comparative Study of the Optical and Textural Properties of Tetrapyrrole Macrocycles Trapped Within ZrO₂, TiO₂, and SiO₂ Translucent Xerogels.

The entrapping of physicochemical active molecules inside mesoporous networks is an appealing field of research due to the myriad of potential applications in optics, photocatalysis, chemical sensing, and medicine. One of the most important reasons for this success is the possibility of optimizing the properties that a free active species displays in solution but now trapped inside a solid substrate. Additionally it is possible to modulate the textural characteristics of substrates, such as pore size, specific surface area, polarity and chemical affinity of the surface, toward the physical or chemical adhesion of a variety of adsorbates.