Shape-dependent adsorption of CeO2 nanostructures for superior organic dye removal

Highly efficient removal of dye pollutants from water resources remains a great challenge. Herein, we demonstrate a new approach for the efficient removal of anionic organic dyes from wastewater using shape-dependent CeO2 nanostructures. It was found that the volume stoichiometry ratio of ethanol to water (EtOH/H2O) was a key factor affecting the CeO2 nanostructures. Accordingly, the adsorption capacity of the spindle CeO2 nanostructure for Congo red reached 162.4 mg g-1, which is much higher than that of octahedral and spherical CeO2 or other adsorbents previously reported. The superior adsorption performance may be mainly attributed to the peculiar structure and presence of electrostatic interactions between the sample surface and dye molecules. This finding will provide new avenues for using promising adsorbent materials for dye removal in water treatments.