CeO2-layered aluminosilicate nanohybrids for UV screening

This study reports a solution route to heterostructured cerium oxide-layered silicate nanohybrid as an inorganic UV ray absorber. Na-montmorillonite, one of the aluminosilicate clay minerals having a cation exchange capacity (CEC of 100 meq/100 g), was adopted as a host material for CeO2. The CeO2-montmorillonite nanohybrids have been synthesized through a conventional ion exchange reaction between Na+ in montmorillonite (MMT) and Ce4+ in aqueous solution, where the positively charged CeO2 nanoparticles are intercalated into the aluminosilicate clay. Powder X-ray diffraction (PXRD) measurements and transmission electron microscope (TEM) observations show that aluminosilicate layers are pillared with the cerium species without surface deposition. The CeO2-montmorillonite nanohybrids showed excellent UV-shielding capacity and high reflectance in the visible light region without any post annealing treatment as compared to the pristine montmorillonite. Finally, photocatalytic activity measurements suggest that surface activity of the CeO2 nanoparticles was effectively reduced by hybridization with the montmorillonite. On the basis of the present results, the present CeO2-montmorillonite nanohybrid is expected to be applicable as an acceptable UV ray screening material. (C) 2012 Published by Elsevier Ltd.