Structural, photoluminescent, and dielectric properties of Eu3+-doped Ba0.7Sr0.3TiO3 thin films

Eu3+-doped Ba0.7Sr0.3TiO3 thin films were prepared by a chemical solution deposition method and characterized by X-ray diffraction, field emission scanning electron microscopy, photoluminescence and dielectric measurements. The thin films were well crystallized with a pure perovskite structure. A contraction of the unit cell was observed upon incorporation of Eu3+ ions below 2 mol%, while an expansion occurred as the Eu3+ concentration was further increased above 2 mol%, indicating that Eu3+ ions with different concentrations occupied different lattice sites. Photoluminescence spectra showed two prominent transitions of Eu3+ ions at 594 nm (D-5(0) -> (7)F1()) and 618 nm (D-5(0) -> F-7(2)) upon excitation at 395 nm (F-7(0) -> L-5(6)). There existed two quenching concentrations at 2 mol% and 4 mol% due to different lattice sites of the Eu3+ ions. We also investigated the dielectric properties of the thin films. Our study suggests that Eu3+-doped Ba0.7Sr0.3TiO3 thin films have potential applications in multifunctional optoelectronic devices. (C) 2015 Elsevier B.V. All rights reserved.