title: Alkali Niobate and Tantalate Perovskites as Alternative Photocatalysts.
abstract: Alkali tantalates and niobates are listed as important photocatalysts for the development of renewable energy technologies and environmental remediation. Herein, the photocatalytic degradation of methylene blue dye in aqueous solution by using highly crystalline particles with perovskite-like structures, LiTaO3, LiNbO3, NaTaO3, NaNbO3, KNbO3, and KTaO3, is investigated. It is demonstrated that ferroelectric KNbO3is the most efficient photocatalyst of those tested because it combines an electronic band structure that can respond successfully to UVA light with a relatively high surface energy that enhances the catalytic properties. Additionally, the built-in electric field due to internal polarization of ferroelectric particles may contribute to the unique properties of this functional photocatalyst. This work provides an ideal platform for the rational design of more efficient ferroelectric-based photocatalytic devices.
authors.affiliation: CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Sebastian
authors.identifier: http://orcid.org/0000-0003-3891-5209
authors.initials: S
authors.lastname: Zlotnik
authors.affiliation: CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: David M
authors.identifier: http://orcid.org/0000-0002-0112-8570
authors.initials: DM
authors.lastname: Tobaldi
authors.affiliation: CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Paula
authors.identifier: http://orcid.org/0000-0002-5174-7433
authors.initials: P
authors.lastname: Seabra
authors.affiliation: CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: João A
authors.identifier: http://orcid.org/0000-0003-4782-1685
authors.initials: JA
authors.lastname: Labrincha
authors.affiliation: CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193, Aveiro, Portugal.
authors.forename: Paula M
authors.identifier: http://orcid.org/0000-0001-5161-1360
authors.initials: PM
authors.lastname: Vilarinho
keywords: methylene blue; niobium; perovskite phases; photocatalytic degradation; tantalum