Next Article in Journal
Ferromagnetic Oxime-Based Manganese(III) Single-Molecule Magnets with Dimethylformamide and Pyridine as Terminal Ligands
Previous Article in Journal
Simultaneously Improve White LED Omni-Directional Package Efficacy and Spatial Color Uniformity on Scattered Photon Extraction Technology
Article Menu
Issue 1 (January) cover image

Export Article

Open AccessArticle
Crystals 2019, 9(1), 22;

Annealing Control on the Anatase/Rutile Ratio of Nanostructured Titanium Dioxide Obtained by Sol-Gel

Tecnológico de Estudios Superiores de Jocotitlán, Carretera Toluca Atlacomulco Km 44.8, Ejido de San Juan y San Agustín, Jocotitlán C.P. 50700, Mexico
Laboratorio de Investigación y Desarrollo de Materiales Avanzados, Facultad de Química, Universidad Autónoma del Estado de México, Carretera Toluca-Atlacomulco Km 14.5, Toluca C.P. 50200, Mexico
Author to whom correspondence should be addressed.
Received: 19 November 2018 / Revised: 15 December 2018 / Accepted: 24 December 2018 / Published: 30 December 2018
PDF [6854 KB, uploaded 14 January 2019]


According to the different phases at which titanium dioxide (TiO2) crystallizes, previous studies have shown that anatase is more efficient for photocatalysis than rutile. Nowadays, the synergetic effect is well-accepted between anatase and rutile as having an effect in increasing performance in photocatalysis. In the present work, control over the anatase/rutile ratio was performed in three experimental steps. Initially, amorphous-anatase TiO2 powders were synthesized by the sol-gel method. For the crystallization of anatase, the powders were annealed at 250 °C for 2 h in ambient atmosphere. The final step was performed by using different annealing times, ranging from 35 up to 200 min at a temperature of 475 °C. The powders were characterized by Raman spectroscopy, UV–VIS, SEM and TEM techniques to determine the crystalline phase, band gap, morphology, and elemental composition, respectively. It was possible to control the anatase/rutile ratio on the nanostructured TiO2 powders from 100% of anatase until a complete transformation to rutile through the variation of the annealing time. The band gap calculated using the Tauc’s model was found in the range of 2.56 to 2.93 eV. However, no direct relationship between the anatase/rutile ratio, and the band gap was found. View Full-Text
Keywords: titanium dioxide; mixed phase; nanoparticle size titanium dioxide; mixed phase; nanoparticle size

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Castrejón-Sánchez, V.H.; López, R.; Ramón-González, M.; Enríquez-Pérez, Á.; Camacho-López, M.; Villa-Sánchez, G. Annealing Control on the Anatase/Rutile Ratio of Nanostructured Titanium Dioxide Obtained by Sol-Gel. Crystals 2019, 9, 22.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Crystals EISSN 2073-4352 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top