N-F codoped TiO 2 films were immobilized on stainless steel sheets through a combined approach involving a dip-coating technique and a hydrothermal treatment, followed by calcination at 400°C in the presence of air. Photocatalyst characterization was conducted using XRD, Raman and UV-VIS spectroscopy as well as SEM. The films were tested in a three-electrode cell for the photoelectrocatalytic degradation of CN-containing compounds. The results showed that the increase in the degradation rate of CN-containing compounds is both influenced by a synergistic effect of the doping agents and strongly dependent on the concentration of CN-containing compounds in the solution. Nitrogen contributed to the enhanced photoactivity under visible light due to the generation of localized states within the band gap of TiO 2 , whereas the presence of fluoride improved the superficial properties of the film, which resulted in higher amounts of CN-containing compounds that were degraded by direct charge transfer through the photogenerated holes.

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Macroporous ceramic foams are used in different fields due to their unique properties, which include: low density, low thermal conductivity, high permeability, high temperature stability and high resistance to chemical attack. Highly porous silicon carbide (SiC) foams are materials of great interest for absorption, catalytic support, and thermal insulation applications, among others, due to their chemical resistance, large surface area, low flow resistance, low pressure drop, as well as high resistance to temperature and corrosion. In this work, highly porous, SiC foams were fabricated via template replica, using recycled polymeric foams as sacrificial templates. A sucrose-based resin containing silica powder was used as a foam precursor. Polymeric templates were impregnated, followed by thermal treatment at 1500 °C under inert atmosphere. The effect of C/SiO2 mass ratio (1.0-1.75) in the precursor and the use of alumina (0.5 - 2.5 %wt/v) as a sintering additive were evaluated in terms of the morphology of the fabricated foams, as well as SiC yield.