The Composite Structure and Two-Peak Emission Behavior of a Ca1.5Ba0.5Si5O3N6:Eu2+ Phosphor

• Published in: Inorganic chemistry 2016-03, Vol.55 (5), p.2534-2543
• Main Authors: Park, Woon Bae, Kim, Hyunmin, Park, Hwangseo, Yoon, Chulsoo, Sohn, Kee-Sun
• Format: Article
• Language: English
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/acs.inorgchem.5b02884

A Ca1.5Ba0.5Si5O3N6:Eu2+ phosphor with a monoclinic lattice in the Cm space group exhibiting a composite structure consisting of CaSi2O2N2-like and BaSi6N8O-like structures was examined in terms of structure and luminescence. The luminescent properties of the Ca1.5Ba0.5Si5O3N6:Eu2+ phosphor could be suitable for light-emitting diode applications since it exhibited a promising yellow (or amber) emission peaking at ∼570–590 nm at excitations of 450–460 nm. The present investigation was focused on verifying the composite structure by employing quantum mechanical calculations such as the Hartree–Fock ab initio calculation and a density functional theory calculation along with precise structural and compositional analyses. The two-peak emission behavior ascribed to the composite structure was also examined in terms of continuous wave and time-resolved photoluminescence. In addition, the energy transfer between two activator sites ascribed to the composite structure was examined in detail.