Spectroscopic Investigation of the Europium(3+) Ion in a New ZnY4W3O16 Matrix

Abstract

AbstractA new Zn and Eu tungstate was characterized by spectroscopic techniques. This tungstate, of the formula ZnEu4W3O16, crystallized in the orthorhombic system and was synthesized by a solid‐state reaction. It melts incongruently at 1330°. The luminescent properties, including excitation and emission processes, luminescent dynamics, and local environments of the Eu3+ ions in ZnEu4W3O16 and ZnY4W3O16 : Eu3+ diluted phases (1, 5, and 10 mol‐% of Eu3+ ion) were studied basing on the f6‐intraconfigurational transitions in the 250–720 nm spectral range. The excitation spectra of this system (λem 615 and 470 nm) show broad bands with maxima at 265 and 315 nm related to the ligand‐to‐metal charge‐transfer (LMCT) states. The emission spectra under excitation at the O→W (265 nm) and O→Eu3+ (315 nm) LMCT states present the blue‐green emission bands. The emission of tungstate groups mainly originate from the charge‐transfer state of excited 2p orbitals of O2− to the empty orbitals of the central W6+ ions. On the other hand, in the emission of the Eu3+ ions, both the charge transfer from O2− to Eu3+ and the energy transfer from W6+ ions to Eu3+ are involved. The emission spectra under excitation at the 7F0→5L6 transition of the Eu3+ ion (394 nm) of ZnY4W3O16 : Eu3+ diluted samples show narrow emission lines from the 5D3, 5D2, and 5D1 emitting states. The effect of the active‐ion (Eu3+) concentration on the colorimetric characteristic of the emissions of the compound under investigation are presented.