Effects of replacement of AlO+ for SiN+ on the structure and optical properties of Sr2Si5N8:Eu2+phosphors

• Published in: Journal of luminescence 2014-03, Vol.147, p.173-178
• Main Authors: Wang, Ting, Zheng, Peng, Liu, Xiaolang, Chen, Haifei, Bian, Liu, Liu, Q.L.
• Format: Article
• Language: English
• Subjects: Aluminum; Atomic structure; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystal structure; Emission; Energy transfer; Exact sciences and technology; Lattice dynamics; Luminescence; Materials science; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Phonon states and bands, normal modes, and phonon dispersion; Phonons and vibrations in crystal lattices; Phosphors; Photoluminescence; Physics; Sr2Si5N8; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Treatment of materials and its effects on microstructure and properties
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2013.11.016

The influence of the replacement of SiN+ by AlO+ on crystal structure and luminescence properties is reported in a series of Sr2Si5−xAlxN8−xOx:0.02Eu2+ phosphors. Changes of refined lattice parameters of the powder X-ray diffraction data suggest that preferential occupation occurred in the evolution of crystal structure: only NII atoms which are connected with two Si atoms can be substituted by O atoms. It is evidenced that Al and O have adverse influence on the emission bands, which just keep the emission peak position around 620nm. Time-resolved photoluminescence analysis has been employed to describe the energy transfer in Sr2Si5−xAlxN8−xOx:Eu2+ samples. The energy transfer effect depends partly on lattice vibration, i.e. phonon energy. Furthermore, the improved photoluminescence intensity and thermal quenching behavior after substituting of AlO+ for SiN+ allowed Sr2Si5−xAlxN8−xOx:0.02Eu2+ a promising candidate as a red phosphor in the white LED applications when x≤0.4. •Sr2Si5−xAlxN8−xOx:Eu2+ phosphors have been synthesized by alloy-nitridation method.•Preferential occupation of O atoms is confirmed.•Al and O have an adverse influence on the emission bands.•The energy transfer involves in phonon-assisted processes.•Thermal quenching behaviors were improved after substituting of AlO+ for SiN+.