Effect of Eu3 + concentration on the photocatalytic activity of LaSr2AlO5 powders

• The photocatalytic activity of LaSr2AlO5:Eu3 + (LSA:Eu) powders is studied under UV irradiation.
• The presence of Eu ions enhances the photocatalytic activity of the LSA:Eu powders.
• Total degradation of methylene blue is obtained after 360 min using the LSA:Eu (10.0 at.%) powders.

The photocatalytic activity of LaSr2AlO5:Eu3 + (LSA:Eu) ceramic powders was studied by monitoring the degradation of methylene blue (MB) dye in water under UV excitation (253 nm). Several LSA:Eu samples were fabricated with Eu3 + concentrations from 1 to 10 at.%. XRD patterns show a single tetragonal phase for all LSA:Eu samples. Scanning electron micrographs of the ceramic powders depicted coalesced particles with average sizes in the range of 3.5–4.27 μm. The optical bandgap of these powders varies between 4.7 eV and 5.1 eV depending on the Eu3 + concentration. The results of photocatalytic activity indicate that MB degradation rate increases as the Eu content increases. In fact, total MB degradation is reached after 360 min under UV light by using LSA:Eu (10 at.%) powders, and these can be removed easily after photocatalytic water treatment. Thus, LSA:Eu powders could be potential photocatalyst for water cleaning applications.

a) Unit-cell schematic representation of LaSr2AlO5:Eu3 +. The spheres represent the following atoms: La/Eu (purple), Sr (green), Al (yellow) and O (red). b) LaO8 coordination formed by the La atom and the O atoms which is similar to the Eu and O atoms' coordination EuO8. c) Integrated absorbance bar graph of methylene blue solution catalyzed with LSA:Eu (10 at.%) photocatalyst powder as a function of time. The inset shows photographs of the solution with MB at the beginning (0 min) and at the end of the experiment (360 min).Figure optionsDownload as PowerPoint slide