Preparation and characterization of YAG microspheres doped with Eu2+/Eu3+ for broad band emission
Marzieh Ghadamyari,
Róbert Klement,
Hossein Ebrahim Hosseini,
Milan Parchovianský,
Jozef Kraxner,
Dušan Galusek,
Sathya Narayanasamy,
Erwin Hack,
Gurdial Blugan,
Monika Michálková
Affiliations
Marzieh Ghadamyari
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia
Róbert Klement
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia; Corresponding author.
Hossein Ebrahim Hosseini
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia
Milan Parchovianský
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia
Jozef Kraxner
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia
Dušan Galusek
FunGlass – Centre for Functional and Surface Functionalized Glass, TnUAD, Trenčín, Slovakia; Vitrum Laugaricio – Joint Glass Centre of the IIC SAS, TnUAD, FChPT STU and RONA, a.s., Študentská 2, SK-911 50, Trenčín, Slovakia; Corresponding author.
Sathya Narayanasamy
CEA, DES, ISEC, DPME, University of Montpellier, Marcoule, F-30207, Bagnols sur Cèze, France
Erwin Hack
Transport at Nanoscale Interfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland
Gurdial Blugan
Laboratory for High Performance Ceramics, Empa – Swiss Federal Laboratories for Materials Science and Technology, CH-8600, Dübendorf, Switzerland
Monika Michálková
Vitrum Laugaricio – Joint Glass Centre of the IIC SAS, TnUAD, FChPT STU and RONA, a.s., Študentská 2, SK-911 50, Trenčín, Slovakia; Corresponding author.
Achieving full-spectrum lighting is a major challenge for phosphor-converted light-emitting diodes (pc-LEDs), which are crucial for solid-state lighting. This study presents the synthesis of polycrystalline Eu-doped Y3Al5O12 (YAG) phosphors through a sol-gel method and flame synthesis process, leading to XRD amorphous microspheres. The amorphous nature of the microspheres allows the reduction of Eu3+ to Eu2+ at a significantly lower temperature (800 °C) than the reduction of crystalline samples described in the literature (1400 °C). The presence of Eu2+ in the YAG lattice was confirmed by X-ray photoelectron spectroscopy (XPS). The X-ray diffraction (XRD) of samples annealed in reducing atmosphere confirmed partial crystallization of pure YAG in all examined samples. The Eu-doped YAG phosphor embedded in residual glass microspheres exhibited a broadband emission spectrum over the wavelength range 450–800 nm peaking at 565 nm, corresponding to the 4f65d1→ 4f7 electron transition within the Eu2+ ions.
