Anatase-Dominant TiO2 Nanoparticles Prepared by Sol–Gel and High-Temperature Calcination
Por:
Acosta-Silva Y.J., Ledesma-García J., Rivas S., Alvarez A., Palma-Tirado L., Pérez-Robles J.F., Méndez-López A.
Publicada:
1 ene 2026
Resumen:
© 2026 by the authors.TiO2 nanoparticles were synthesized by a simple sol–gel route followed by high-temperature calcination at 800 °C, aiming to obtain an anatase-dominant reference photocatalyst with enhanced structural stability after severe thermal treatment. Raman spectroscopy and X-ray diffraction confirmed that anatase is the major crystalline phase, with only a minor rutile contribution after calcination at 800 °C. Nitrogen adsorption–desorption measurements revealed a narrow mesoporous contribution arising from interparticle voids and a relatively high specific surface area (108 m2 g-1) despite the severe thermal treatment, while electron microscopy showed nanometric primary particles assembled into compact agglomerates. Surface hydroxyl groups were identified by Fourier-transform infrared spectroscopy, consistent with sol–gel-derived TiO2 systems. Diffuse reflectance UV–Vis spectroscopy combined with Kubelka–Munk and Tauc analysis yielded an optical band gap of 3.12 eV, typical of anatase TiO2. Methylene blue (MB) was used as a probe molecule to evaluate photocatalytic activity under ultraviolet and visible light irradiation. Under UV illumination, degradation kinetics were governed by band-gap excitation and reactive oxygen species generation, whereas a slower but reproducible reference behavior under visible light was predominantly associated with surface-related effects and dye sensitization rather than intrinsic visible-light absorption. Overall, the results establish this anatase-dominant TiO2 as a reliable high-temperature reference photocatalyst, retaining measurable activity after calcination at 800 °C and exhibiting UV-driven behavior as the dominant contribution.
Filiaciones:
Acosta-Silva Y.J.:
Cuerpo Académico de Nanotecnología y su Aplicación (UAQ-CA-160), Facultad de Ingeniería, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Las Campanas, Querétaro, 76010, Mexico
Ledesma-García J.:
Cuerpo Académico de Catálisis (UAQ-CA-126), Facultad de Ingeniería, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Las Campanas, Querétaro, 76010, Mexico
Rivas S.:
Cuerpo Académico de Nanotecnología y su Aplicación (UAQ-CA-160), Facultad de Ingeniería, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Las Campanas, Querétaro, 76010, Mexico
Alvarez A.:
Cuerpo Académico de Catálisis (UAQ-CA-126), Facultad de Ingeniería, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Las Campanas, Querétaro, 76010, Mexico
Palma-Tirado L.:
Unidad de Microscopía, Microscopía Electrónica de Transmisión, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro, 76230, Mexico
Pérez-Robles J.F.:
Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Querétaro, 76230, Mexico
Méndez-López A.:
Cuerpo Académico de Nanotecnología y su Aplicación (UAQ-CA-160), Facultad de Ingeniería, Universidad Autónoma de Querétaro, Cerro de las Campanas s/n, Las Campanas, Querétaro, 76010, Mexico
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