Synthesis, crystal structure and luminescence properties of CaY2-xEuxGe3O10 (x=0-2)

The novel red emitting phosphors based on CaY2-xEuxGe3O10 (x=0-2) have been prepared using both a conventional solid-state reaction and a synthesis route via EDTA-complexing process. Powder XRD study has revealed that CaY2-xEuxGe3O10 (x=0.1-0.8, 2.0) crystallizes in the monoclinic space group P2(1)/c, Z=4. The trivalent europium ions occupy three different sites (4e) with the C-1 symmetry. The phosphors exhibit a strong red emission under excitations at 250 nm and 393 nm. The light emission efficiency depends on the excitation wavelength, the activator content and the method of synthesis. Appropriate CIE chromaticity coordinates for CaY1.7Eu0.3Ge3O10 are x=0.54 and y=0.29. (C) 2013 Elsevier Inc. All rights reserved.