Chemical Engineering Journal, Vol.317, 854-861, 2017
Tuning excitation and emission of Mn4+ emitting center in Y3Al5O12 by cation substitution
Recently, Me4+ doped oxide red phosphors have been attracted great attention for promising application in white light-emitting diode to improve optoelectronic properties. Unfortunately, most of Mn4+ doped oxide phosphors suffer from low absorption excitation in blue light region and deep red emission. In this work, taking Y(3)AI(5)O(12) as the Me4+ doped host, we demonstrate the tunability of excitation and emission of Me4+ activator via cation substitution. X-ray diffraction patterns confirm that y(3+) and Al3+ in the host can be completely replaced by Gd3+/Lu3+ and Ga3+, respectively. Impressively, the substitution of AI(3+) ions by Ga3+ ones is beneficial to significantly enhance Mn(4+4)A(2) () T-4(2) blue excitation band and shift E-2 (4)A(2) red emission band toward low-energy region; the replacement of Y3+ by Gd3+ induces red-shifting of both Mn4+ excitation and emission bands while Lu3+ doping leads to the opposite result. These phenomena may be attributed to the doping-induced alteration of Mn4+ local environments, i.e., the covalency of Me4+ ligand field. Finally, inorganic Ce3+: Y(3)AI(5)O(12) and Me4+: Y(3)AI(5)O(12) dual-phase embedded glass ceramic is prepared by a low-temperature co-sintering route to replace phosphors in organic silicone as color converter, and by combining the synthesized glass ceramic with InGaN blue chip, warm white light emitting diode with superior optical performance is successfully realized. (C) 2017 Elsevier B.V. All rights reserved.