Mechanism of X-ray excited optical luminescence (XEOL) in europium doped BaAl₂O₄ phosphor

Abstract

This paper reports a luminescence mechanism in Eu-doped BaAl2O4 excited with monochromatic X-rays (also known as X-ray excited optical luminescence - XEOL) from synchrotron radiation. The material was prepared via a proteic sol-gel methodology. The X-ray absorption near edge structures (XANES) at the Ba LIII- and Eu LIII-edges exhibit typical absorption spectra. XEOL spectra recorded in energy ranges, either around the Ba LIII- or Eu LIII-edges, showed important differences concerning the intensity of the Eu(2+) or Eu(3+) emission bands. Nevertheless, the total area under the XEOL spectra increases as the energy of the X-ray photons increases in both ranges (Ba LIII- and Eu LIII-edges).

Impact of Lanthanide Nanomaterials on Photonic Devices and Smart Applications

“…Cebim et al explained the different stages of the XEOL scintillation process and proposed applications for XEOL materials . Besides, specific investigations on XEOL mechanisms in europium‐doped phosphors were reported by Rezende et al Lanthanide‐doped nanoprobes (NaYF 4 : Er/Yb) capable of X‐ray induced imaging have been reported by Naczynski et al These nanoprobes generate emission centered at 1532 nm and lying in the third infrared biological window (1500–1800 nm), where clear mapping of lymphatic drainage and individual lymph nodes were shown. A X‐ray induced nanoscintillator for both imaging and in vivo cancer treatment was achieved by Chen's group .…”

A comparative study of optical properties and X-ray induced luminescence of octahedral molybdenum and tungsten cluster complexes

“…A few types of nanomaterials have already been considered as contrast agents for XEOL based bioimaging and as photosensitisers including lanthanide doped inorganic nanoparticles, [8][9][10][11][12] gold nanoparticles 13 and MOFs. 14 The potential of octahedral molybdenum cluster complex (Bu 4 N) 2 [{Mo 6 I 8 }(OOC-1-adamantane) 6 ] for X-ray excited optical luminescence and X-ray induced PDT has also been recently revealed in ref.…”

Evaluating Biogenicity on the Geological Record With Synchrotron-Based Techniques

“…However, the excitation with X-rays allows the observation of all optical active channels due to their capability of exciting core levels, making the optical process dependent of the lattice relaxation. Defects may be probed and explored, as well as their characteristics such as oxidation state, origin (intrinsically or extrinsically formed) (Teixeira et al, 2014; Finch et al, 2016; Rezende et al, 2016), and the environment they were formed, for example, when a living organism has started its fossilization process or even why a precious gemstone presents determined color (Tao, 2016).…”