Obtaining Nb₂O₅ by the Sol-Gel route for photocatalytic application

Full text: Sol-gel terminology is used to describe a broad class of materials synthesis processes in which a solid phase (called a gel) is formed by gelling a colloidal suspension (called sol). The drying of this gel can then generate a dry gel and a subsequent heating / calcination treatment is used to remove synthetic residues, stabilize the gel, densify or crystallize it. This synthesis methodology has been used to obtain several oxides, among them, Nb₂O₅. Niobium pentoxide (Nb₂O₅) is known to be a polymorphic ceramic and exhibits semiconductive characteristics, which makes it a potential candidate in the area of photocatalysis [2]. In this work, a colloidal (sol-gel) route was evaluated for synthesis of Nb₂O₅, using the precursor of niobium chloride, ethyl alcohol and distilled water. The properties of the suspension and the obtained powder were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and UV-visible light absorption. The crystalline phase of Nb₂O₅ is determined according to the temperature of the heat treatment. In this work the material was subjected to a temperature of 500 ° C, obtaining the pseudohexagonal phase. The synthesized material will be applied in photocatalytic degradation tests and the results will be analyzed later. [1] L.L. Hench.; J.K.West.; Chem. Rev, 90, 33 1990 [2] O.F.Lopes,et al. Quimica Nova, 36, 106 (2015)[1] L.L. Hench.; J.K.West.; Chem. Rev, 90, 33 1990 [2] O.F.Lopes,et al. Quimica Nova, 36, 106 (2015). (author)