Synthesis and Optical Properties of Cobalt-Modified Titanium Oxide Films

• Published in: Optics and spectroscopy Vol. 126; no. 6; pp. 674 - 680
• Main Authors: Logacheva, V. A., Lukin, A. N., Afonin, N. N., Serbin, O. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-06-2019; Springer Nature B.V
• Subjects: Angle of reflection; Atomic force microscopy; Banded structure; Cobalt oxides; Grain size; Incidence angle; Infrared spectroscopy; Lasers; Magnetic fields; Magnetic properties; Magnetron sputtering; Microscopy; Optical Devices; Optical properties; Optics; Optics of Surfaces and Interfaces; Oxide coatings; Photonics; Physics; Physics and Astronomy; Reflectance; Spectrum analysis; Titanium dioxide; Titanium oxides
• ISSN: 0030-400X; 1562-6911
• DOI: 10.1134/S0030400X19060158

Properties of polycrystalline TiO
2
films modified by magnetron sputtering of cobalt followed by pulsed photon-irradiation processing in air are investigated by methods of X-ray phase analysis, raster electron microscopy, atomic force microscopy, magnetic force microscopy, and IR spectroscopy. Formation of a nanocrystalline (with a grain size of ~50 nm) film consisting of cobalt and titanium oxides the surface of which exhibits magnetic properties is established in the process of modification. The IR reflectance spectra obtained at different angles of incidence in the region between 500 and 600 cm
–1
reveal the presence of two bands belonging to transverse modes (TO) and two corresponding bands belonging to the longitudinal modes (LO). These bands are indicative of formation of Co
3
О
4
with spinel structure. Investigation of optical absorption suggests a predominant existence of phases characterized by direct interband transitions with energies of 1.43 and 1.83 eV for Co
3
O
4
, along with a transition with energy of 2.65 eV for cubic phase of CoO, in the films.