Preparation and photocatalytic properties of magnetically reusable Fe3O4@ZnO core/shell nanoparticles

•Fe3O4@ZnO core/shell nanoparticles were successful synthesized.•The core/shell nanoparticles show excellent photocatalytic activity.•Fe3O4 core ensures core/shell nanoparticles reuse easily in waste water treatment.

Fe3O4@ZnO binary nanoparticles were synthesized by a simple two-step chemical method and characterized using various analytical instruments. TEM result proved the binary nanoparticles have core/shell structures and average particle size is 60 nm. Photocatalytic investigation of Fe3O4@ZnO core/shell nanoparticles was carried out using rhodamine B (RhB) solution under UV light. Fe3O4@ZnO core/shell nanoparticles showed enhanced photocatalytic performance in comparison with the as prepared ZnO nanoparticles. The enhanced photocatalytic activity for Fe3O4@ZnO might be resulting from the higher concentration of surface oxygen vacancies and the suppressing effect of the Fe3+ ions on the recombination of photoinduced electron–hole pairs. Magnetization saturation value (5.96 emu/g) of Fe3O4@ZnO core/shell nanoparticles is high enough to be magnetically removed by applying a magnetic field. The core/shell photocatalyst can be easily separated by using a commercial magnet and almost no decrease in photocatalytic efficiency was observed even after recycling six times.

Graphical abstractMagnetically reusable Fe3O4@ZnO core/shell nanoparticles were synthesized by a simple two-step chemical method. Almost no decrease in photocatalytic efficiency was observed even after recycling six times.Figure optionsDownload full-size imageDownload as PowerPoint slide