Manganese-Doped Composites Based on Titanium Dioxide: Template Sol–Gel Synthesis, Structure, and Properties

• Published in: Russian journal of inorganic chemistry 2022-09, Vol.67 (9), p.1339-1347
• Main Authors: Tkachenko, I. A., Marchenko, Yu. V., Vasilyeva, M. S., Kuryavy, V. G., Gerasimenko, A. V., Polyakova, N. V., Zheleznov, V. V.
• Format: Article
• Language: English
• Subjects: Antiferromagnetism; Catalytic activity; Chemistry; Chemistry and Materials Science; Coercivity; Composite materials; Doping; Ferromagnetism; Indigo; Inorganic Chemistry; Magnetic properties; Magnetic transitions; Manganese; Nanoparticles; Photocatalysis; Room temperature; Sol-gel processes; Synthesis; Synthesis and Properties of Inorganic Compounds; Titanium; Titanium dioxide
• ISSN: 0036-0236; 1531-8613
• DOI: 10.1134/S0036023622090169

Manganese-doped nanostructured composites based on TiO 2 were obtained by the template sol–gel method. By a set of investigation techniques, it was established that manganese doping leads to the appearance of a rutile phase, which grows with increasing manganese content. It was found that during the template sol–gel synthesis of the TiO 2 /Mn composite, the doping element is not only incorporated into the titanium dioxide structure, but also forms separate phases on its surface. Study of the magnetic characteristics of the obtained composites revealed ferromagnetic ordering at room temperature, while lowering the temperature leads to an increase in the coercive force and appearance of the ferromagnet/antiferromagnet type exchange interaction. A magnetic transition at about 43 K, associated with the transfer of Mn 3 O 4 nanoparticles to the ferromagnetic state, was detected in the composites. Undoped titanium dioxide showed a high photocatalytic activity in the visible spectral range, providing 98% degree of indigo carmine degradation. Manganese doping of TiO 2 microtubes inhibited the photocatalytic activity.