Synthesis and characterization of Ce and Er doped ZrO2 nanoparticles as solar light driven photocatalysts

In this work, nanostructured rare-earth-doped zirconia was successfully synthesized, through a simple hydrothermal method, with a rare-earth oxide (REO)-based content varying from 0.5 to 5% molar (REO ¼ CeO2; Er2O3). The samples were characterized by using several techniques, such as X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance spectroscopy. The photoactivity of the samples was tested under irradiation with simulated solar light by both the spin trapping technique, using DMPO (5,5-dimethyl-1-pyrroline-N-oxide) as spin trapping agent, and by the photodegradation of Rhodamine B, a common textile dye. All the doped samples resulted more active than the bare zirconia, and the correlation between the physical-chemical properties and the photoactivity of the materials has been investigated.