Aluminum-silicate based orange-red phosphors with mixed divalent and trivalent cations
View Patent ↗Novel aluminum-silicate based orange-red phosphors, with mixed di- and trivalent cations are disclosed. The phosphors have the formula (Sr 1−x−y M x T y ) 3−m Eu m (Si 1−z Al z )O 5 , where M is at least one of Ba, Mg, Ca, and Zn in an amount ranging from 0≦x≦0.4. T is a trivalent metal in an amount ranging from 0≦y≦0. This phosphor is configured to emit visible light having a peak emission wavelength greater than about 580 nm. The phosphors may contain a halogen anion such as F, Cl, and Br, at least some of which is substitutionally positioned on oxygen lattice sites. The present aluminum-silicate phosphors have applications in white and orange-red illumination systems, as well as plasma display panels.
1. An aluminum-silicate phosphor having the formula (Sr 1−x−y M x T y ) 3−m Eu m (Si 1−z Al z )O 5 , wherein:
M is at least one of a divalent metal selected from the group consisting of Ba, Mg, and Ca;
T is a trivalent metal;
0≦x≦0.4;
0≦y≦0.4;
0≦z≦0.2; and
0.001≦m≦0.5.
2. The aluminum-silicate phosphor of claim 1 , wherein the trivalent metal T is selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, Pa, and U.
3. The aluminum-silicate phosphor of claim 1 , wherein the phosphor further includes a halogen selected from the group consisting of F, Cl, and Br.
4. The aluminum-silicate phosphor of claim 3 , wherein the phosphor is configured such that the halogen resides on oxygen lattice sites within the silicate crystal.