Structural and photoluminescent properties of EuF3 nanoparticles in zeolite A

We report the structural and photoluminescence studies on EuF3-doped zeolite A samples, which were prepared by a diffusion method from liquid to solid state phase. The samples were studied by transmission electron microscopy and by room and low temperature photoluminescence measurements. The microstructural analysis shows that EuF3 crystalline nanoparticles were formed inside the zeolites matrix. The photo-luminescence properties of the EuF3 enclosed in the zeolites show some remarkable differences with those of isolated EuF3 powder. The emission spectra of EuF3-doped zeolite A show a dependence on the excitation wavelength, which was related to excitonic size effects. It was observed emission of the Eu3+-ion excited at a wavelength not corresponding to any excitation line in the excitation spectrum of the Eu3+-ion, as consequence of an energy transfer mechanism. The emission of Eu3+ ions resulting from this energy transfer process indicates that Eu3+-ions have a different symmetry. (c) 2005 Elsevier Ltd. All rights reserved.