Spectral broadening of a single Ce3+-doped garnet by chemical unit cosubstitution for near ultraviolet LED

Abstract

In this paper, the isostructural Mg3Al2Si3O12 was introduced into the Ce3+-doped yttrium aluminum garnet (Y3Al5O12) for synthesizing (Y1-xMgx)3Al2(Al1-xSix)3O12:Ce3+ (x = 0-0.6) solid solution phosphors. The co-substitution of the (Mg, Si)6+ pair for the (Y, Al)6+ pair leads to lattice shrinkage and then changes the spectral shape and width. The band peaking at ~450 nm shows a substantial broadening with the full width at half maximum increasing from 65 nm to 94 nm. The intensity of excitation spectrum (x = 0.5) at 400 nm is increased by 50% than that (x = 0). The near ultraviolet LED was fabricated with Y1.5Mg1.5Al3.5Si1.5O12:Ce3+ phosphors and a 400 nm chip and can emit strong white light. Therefore, by controlling the content of (Y, Al)6+ substituted by (Mg, Si)6+, the excitation spectrum of Ce3+-doped Y3Al5O12 can be tuned and applied for the near ultraviolet LEDs.