title: Controlled Phase Changes of Titania Using Nitrogen Plasma.
abstract: In this work, the development of a new crystallization technique is reported, using nitrogen plasma (AC) to obtain nanostructured anatase and rutile from amorphous titanium oxide (TiO2). This methodology increases throughput and minimizes thermal effects. Nanostructured amorphous TiO2was obtained by the sol-gel method and subsequently subjected to AC treatment, at a controlled pressure, applying different powers and treatment times in order to obtain phase changes. The obtained samples were characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). The results show the crystallization in parallel with anatase and rutile phases with a proportion that is directly related to the applied power in the plasma and the treatment time. This technique allows us to obtain smaller crystals in comparison with those of classic thermal methodologies. It is also demonstrated that the application of plasma represents a novel and innovative method to obtain phase polymorphic changes in titanium oxide without needing to apply prolonged heat treatments at high temperatures and can therefore be taken into consideration as a technique with low energy costs, in comparison with conventional heat treatments.
authors.affiliation: Facultad de Ingeniería Química, Universidad Autónoma de Yucatán, Mérida, Yucatán, 97203, México. rudy.trejo@correo.uady.mx.
authors.forename: R
authors.identifier: http://orcid.org/0000-0002-7407-469X
authors.initials: R
authors.lastname: Trejo-Tzab
authors.affiliation: Facultad de Ingeniería Química, Universidad Autónoma de Yucatán, Mérida, Yucatán, 97203, México.
authors.forename: Liliana
authors.initials: L
authors.lastname: Caballero-Espada
authors.affiliation: Depto. de Física Aplicada, CINVESTAV-Unidad Mérida, A.P. 73, Cordemex, 97310, Mérida, Yucatán, México.
authors.forename: P
authors.initials: P
authors.lastname: Quintana
authors.affiliation: Facultad de Ingeniería Química, Universidad Autónoma de Yucatán, Mérida, Yucatán, 97203, México.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Ávila-Ortega
authors.affiliation: Facultad de Ingeniería, Universidad Autónoma de Yucatán, Mérida, Yucatán, 97203, México.
authors.forename: R A
authors.initials: RA
authors.lastname: Medina-Esquivel
keywords: Nitrogen plasma; Plasma discharge; Plasma treatment; Titania