The structure, anion order, and Ce3+ luminescence of Y4Al2O9–Y4Si2O7N2 solid solutions

Abstract

Oxonitridoalumosilicates Y₄Al_2−2xSi_2xO_9−2xN_2x (0.00 ≤ x ≤ 1.00) were prepared and the substitution effect of [Al³⁺O²⁻] pairs by [Si⁴⁺N³⁻] pairs in Y₄Al₂O₉–Y₄Si₂O₇N₂ solid solutions on the structure and its corresponding influence on the Ce³⁺ activated luminescence properties are investigated. Y₄Al_2−2xSi_2xO_9−2xN_2x (0.00 ≤ x ≤ 1.00) shows two solid solution regions, x = 0.00–0.40 for solid solution I, x = 0.50–1.00 for solid solution II from X-ray and neutron diffraction analysis. In the solid solution I, the Ce³⁺ emission is mainly in the UV range with the maximum wavelength at 350 nm, and the intensity decreases rapidly with the increase of the N content. In the solid solution II, the Ce³⁺ doped samples show blue-green luminescence with the maximum wavelength at ∼450 nm and the wide excitation bands extend from UV to 450 nm. The phosphors in the solid solution II are promising candidates for white-LED applications.