Structure and photoluminescence of composite based on ZnO particles inserted in layered magadiite

A magadiite-ZnO (Mag-ZnO) composite was synthesized from Na-magadiite by two-step ion-exchanges and thermal treatment. Various techniques have been used to characterize the composite. X-ray diffraction (XRD) results found that the basal spacings of the derivatives were different from that of the Na-magadiite. Scanning electron microscope equipped with energy dispersive X-ray (SEM-EDX) was used to estimate the chemical composition of the Mag-ZnO composite. Photoluminescence (PL) spectrum of the Mag-ZnO presents a luminescent peak at 356 nm and a weak shoulder at 456 nm under the excitation of 280 nm. This luminescent peak showed markedly blue shift compared with that of the uncovered ZnO (455 nm), which may be due to the quantum confinement effect of nanoparticles. UV-visible transmission spectra suggested that the Mag-ZnO composite is characteristic of magadiite and ZnO. TEM observation revealed that the ZnO nanoparticles were inserted in the magadiite, and its sizes were estimated to be about 2.5 nm. These results confirmed the formation of Mag-ZnO composite, along with improved photoluminescence of ZnO inserted in the magadiite. (C) 2013 Elsevier B.V. All rights reserved.