Synthesis, optical properties, and enhanced photocatalytic degradation of (Mg, Cu) co-doped TiO2 nanoparticles under ultraviolet light irradiation

Co-precipitation method was used as a quick and effective way to elaborate the Mg and Cu co-doped TiO2 (MgCu/T) nanoparticles. The formation of a single phase (anatase) with a tetragonal structure of nano-crystallized MgCu/T was confirmed by X-ray diffraction (Card No. 89-4203). Experimental results indicate that the synthesized MgCu/T nanoparticles are nanometric, ranging from 12 to 25 nm, consistent with the findings from SEM images. Additionally, the UV-Vis reflectance spectra showed that MgCu/T nanoparticles possess strong absorption properties in the UV-visible region. Hence, the photocatalytic activities showed that the 4 mol% Mg-doped MgCu/T nanoparticles exhibited the highest activity as a photocatalyst under ultraviolet light. The maximum degradation was found to be 58% for the sample 4 mol% Mg-doped MgCu/T nanoparticles after 210 min of UV light irradiation. The increase in AC conductivity of MgCu/T nanoparticles with higher Mg concentrations can be attributed to the fact that Mg doping introduces shallow donor states in TiO2. These states can more easily donate electrons to the conduction band, thus increasing the charge carrier concentration.