Solid-solution transformation and photoluminescence control in Ce3+-doped Ln4Si2-xMxO7+xN2-x (Ln = Y, Lu; M = B, Al, P) oxonitridosilicate phosphors

Abstract

By designing diverse composition substitutions in phosphor materials to construct solid solution phase transformation are effective strategies to adjust the luminescence properties of phosphor materials. In this study, the Ce3+-doped Y4Si2O7N2 is selected as template material to design a series of composition substitutions including [Y3+-Lu3+] cation substitution, and [SiN+-AlO+] cation-anion cosubstitution, [B3+/P5+-Si4+] substitutions for tuning photoluminescence property and thermal stability of the as-prepared solid solution phosphors. According to XRD and Rietveld refinement results, the Ln4Si2-xAlxO7+xN2-x:Ce3+ (Ln = Y, Lu) could form perfect solid solution phases at 0 ≤ x ≤ 1 in terms of the same monoclinic structure of Ln4Si2O7N2-Ln4Al2O9 with space group P21/a (14). While B- and P-doping only remain the solid solution phase at a low substitution ratio. Continuous spectral blue shift in the blue-green region and improved thermal stability are observed in Ln4Si2-xAlxO7+xN2-x:Ce3+ (Ln = Y, Lu) and B/P-doped Y4Si2O7N2:Ce3+ systems, which are possibly attributed to the enlarged crystal lattice environment around Ce3+ ions with the [SiN-MO] (M = B, Al, O) cosubstitutions. In addition, the red-shift emission of Y4Si2O7N2:Ce3+ with the increase of Ce3+ concentrations are also discussed. In summary, this study systematically discussed the effect of the diverse composition substitutions on the luminescence properties, which could serve as a guide in developing novel oxonitridosilicate luminescent materials with controllable optical properties.