Influence of Mg, Cu, and Ni Dopants on Amorphous TiO2 Thin Films Photocatalytic Activity

Vytautas Kavaliunas; Edvinas Krugly; Mantas Sriubas; Hidenori Mimura; Giedrius Laukaitis; Yoshinori Hatanaka

doi:10.3390/ma13040886

Influence of Mg, Cu, and Ni Dopants on Amorphous TiO₂ Thin Films Photocatalytic Activity

Materials (Basel). 2020 Feb 17;13(4):886. doi: 10.3390/ma13040886.

Authors

Vytautas Kavaliunas^{1

2}, Edvinas Krugly³, Mantas Sriubas¹, Hidenori Mimura⁴, Giedrius Laukaitis¹, Yoshinori Hatanaka⁴

Affiliations

¹ Department of Physics: Faculty of Mathematics and Natural Sciences, Kaunas University of Technology, Studentų str. 50, 51368 Kaunas, Lithuania.
² Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-Ku, Hamamatsu, Shizuoka 432-8011, Japan.
³ Faculty of Chemical Technology, Kaunas University of Technology, Radvilėnų pl. 19, 50299 Kaunas, Lithuania.
⁴ Research Institute of Electronics, Shizuoka University, 3-5-1 Johoku, Naka-Ku, Hamamatsu, Shizuoka 432-8011, Japan.

Abstract

The present study investigates Mg (0 ÷ 17.5 wt %), Cu (0 ÷ 21 wt %) and Ni (0 ÷ 20.2 wt %) dopants (M-doped) influence on photocatalytic activity of amorphous TiO₂ thin films. Magnetron sputtering was used for the deposition of M-doped TiO₂ thin films. According to SEM/EDS surface analysis, the magnetron sputtering technique allows making M-doped TiO₂ thin films with high uniformity and high dopant dispersion. Photocatalysis efficiency analysis was set in oxalic acid under UV irradiation. In accordance with the TOC (total organic carbon) measurements followed by the apparent rate constant (k_app) results, the dopants' concentration peak value was dopant-dependent; for Mg/TiO₂, it is 0.9% (k_app-0.01866 cm^-1), for Cu/TiO₂, it is 0.6% (k_app-0.02221 cm^-1), and for Ni/TiO₂, it is 0.5% (k_app-0.01317 cm^-1). The obtained results clearly state that a concentration of dopants in TiO₂ between 0.1% and 0.9% results in optimal photocatalytic activity.

Keywords: amorphous materials; catalytic properties; photocatalysis; sputtering; titanium dioxide thin films.