Fabrication of doped Titania (TiO2) nanofibers to serve as catalysts in NH₃-Selective CatalyticReduction (SCR)

摘要

In a context of significant interest for energy and environment, nanostructured-based ceramic materials areconsidered ideal candidates for the development of cost and energy efficient innovative systems. Such anattention is essentially due to the unique properties originating from the confinement of either one or moredimensions into the nanoscale level. Among others the large surface-to-volume ratio is a feature that greatlyincreases the reactivity of the nanomaterials towards gaseous species when compared with the non-nanodimensional materials. With this regards, catalysis is one of those applications that unquestionable benefitsfrom this novel feature. In addition, when nanofibers (1D nanostructure) are used as catalysts, the furtheradvantage of a self-supported wide open and well-interconnected porous structure is achieved.Herein we demonstrate nanofibers as catalysts for the removal of the NOx in exhausts via the NH3 SelectiveCatalytic Reduction (SCR) method. By combining electrospinning and sol-gel chemistry, materials areprocessed as nanofibers with the catalytic components (e. g. VO-WO) incorporated as dopants into thesupporting anatase phase (e. g TiO). Remarkable high NOx conversion efficiencies are obtained andassociated with the unique features deriving from the synergism among the doping approach, the nanoscaleconfinement, and the nano-fibrous texture. A novel concept of self-supported, lightweight and ultra-compactdesign SCR reactor is defined.