Photocatalytic performance of cementitious materials with addition of red mud and Nb2O5 particles. (30th October 2020)

• Record Type: Journal Article
• Authors: Moreira, Michelle A.N.S.; Heitmann, Ana P.; Bezerra, Augusto C.S.; Patrício, Patrícia S.O.; de Oliveira, Luiz C.A.; Castro, Cinthia S.; de Souza, Patterson P.
• Is Part Of: Construction & building materials. Volume 259(2020)
• Publication Date: 2020-10-30
• Subjects: Photocatalysis -- Red mud -- Niobium pentoxide -- Mortar; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.119851
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The materials exhibited catalytic activity for the oxidation of methylene blue dye using UV radiation. The use of red mud in cementitious materials presents an environmental alternative. The addition of red mud or Nb2O5 in cementitious materials providing a useful destination for the residue. Cementitious materials with additives have the potential for use as self-cleaning materials. Abstract: In this work, Nb2 O5 and red mud (RM) were separately added to Portland cement for application as photocatalysts using visible (vis) and ultraviolet (UV) light. The resultant materials, i.e., mortar/RM and mortar/Nb2 O5, were characterized by UV–vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy-attenuated total reflectance, thermogravimetry, photocatalytic tests, and scanning electron microscopy. The characterization results showed that the Nb2 O5 and RM particles were micrometric and that their mixtures with mortar exhibited homogeneous and uniform morphologies. The addition of the particles modified the bandgap value of mortar and improved its photocatalytic performance. The materials exhibited catalytic activity for the oxidation of methylene blue dye using UV radiation. In addition, the mortar/RM showed the best performance in the removal of methylene blue dye while the photocatalytic activity of Nb2 O5 was compromised when it was mixed with mortar. It is noteworthy that cementitious materials with additives have the potential for use in self-cleaning surfaces.