Preparation of Red-Emitting Eu²⁺-Doped Barium Calcium Silicon Oxynitride by Solid-State Reaction and its Luminescence Properties

Abstract

The luminescence properties of Eu2+-doped barium calcium silicon oxynitrides (general formula: Ba4-xCaxSi6ON10: Eu2+ (x= 1.8 ~ 2.2)) were examined, together with the preparation conditions for the solid state reaction. Firstly, the stoichiometric amounts of Ba, Ca3N2, SiO2 and Si3N4 were mixed with Eu2O3 (activator; the molar ratios of Eu to (Ca + Ba + Eu) (= m; 0.05 to 1.0)) for the preparation of Ba1.8Ca2.2Si6ON10: Eu2+, Ba2.0Ca2.0Si6ON10: Eu2+ and Ba2.2Ca1.8Si6ON10: Eu2+, and then the mixtures were heated at a temperature between 1300 and 1550°C for 10 h in N2 atmosphere. The single phase compounds, which were prepared by the heating at and above 1350°C, emitted the red color light whose wavelength could be changed from 638 to 653 nm with increasing m value from 0.05 to 1.00, due to the excitation at the wavelength of 528 nm.