Synthesis, characterization, and photocatalytic performance of Cu/Y co-doped TiO2 nanoparticles

Cu and Y co-doped TiO2 nanoparticles were prepared with an acid-catalytic sol-gel process. XRD and Raman spectroscopy confirm the single anatase phase in all samples with a reduced crystallite size upon doping. SEM observations reveal uniform nanospheres (20-40 nm) being synthesised under the proposed processing conditions. The absorption edge shifts to the visible light region, as indicated by bandgap energy reduction. XPS results demonstrate that the Cu and Y dopants exist in the state of Cu+ and Y3+ ions, respectively. The dopant elements might have been doped into TiO2 lattice by substituting Ti4+ and generating oxygen vacancies for charge compensation. The photoactivity of the Cu/Y co-doped TiO2 is better than that of the undoped one, with the optimum doping concentration being 1.0 mol%. The improved photocatalytic performance is attributed to the effective separation of photon-generated electron-hole pairs, increased formation of active radicals, and increased surface area in the co-doped photocatalysts.