Degradation of Titanium Sintered with Magnesium: Effect of Hydrogen Uptake

Multifunctional materials based on a combination of permanent and degradable metals open new perspectives for medical implants combining osseoconductivity and drug-delivery functions which can significantly decrease the number of implants’ revision. In this work, hybrid magnesium-titanium materials were produced via sintering, and the properties of the permanent titanium component before and after the degradation of the temporary magnesium part were evaluated. The changes of chemical composition and mechanical parameters were determined. Loading of hydrogen into the titanium part at room temperature was observed, which deteriorated the mechanical characteristics but could also simultaneously improve the biocompatibility of the permanent titanium implant. The control of degradation of the magnesium part and the modification of the titanium part are required for the development of partly degradable hybrid implants.

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

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.