Structure and luminescent properties of electrodeposited Eu3+-doped CaF2 thin films

The crystal structure and photoluminescence properties of CaF2 films doped with varied concentrations of Eu3+ ions prepared via the facile electrodeposition method under mild conditions have been systematically studied. The lattice parameters of the electrodeposited Ca(1-x)F(2+x):Eu-x (x: 0-0.30) increase with the increasing doping concentration of Eu3+ due to the charge compensation by additional fluoride interstitial ions. The high ratio of photoluminescence intensity between the magnetic dipole transition (D-5(0)-> F-7(1)) at 590 nm and the electron dipole transition (D-5(0)-> F-7(2)) at 614 nm of Eu3+ in all electrodeposited films indicates that the dominant europium ions are situated at the site with high symmetry in the CaF2 host. With the increase of the Eu3+ concentration, the photoluminescence quantum yield shows a tendency of decreasing, and the highest quantum yield of film is about 64.24%. (C) 2014 Elsevier B.V. All rights reserved.