Fluorescent material and light-emitting device
There is provided a fluorescent material having a composition represented by the following Formula (1). (Sr a ,Ba b ,Eu x ,M 1 1 ,M 2 e )SiO f ·cMgO . . . Formula (1) (In the formula, M 1 is at least one tertiary group element selected from Y and Tb; M 2 is an alkali metal selected from Li, Na, and K; and 0<a<2, 0<b<2, 0≦c<1, 0.001≦d≦0.06, 0≦e≦0.06, 0<x<0.1, and 3.7≦f≦4.1 are set.) Further, there is provided a light-emitting device including: the fluorescent material; and a light source irradiating the fluorescent material with excitation light to cause the fluorescent material to emit light.
1. A fluorescent material having a composition represented by the following Formula (1):
(Sr a ,Ba b ,Eu x ,M 1 d ,M 2 e )SiO f c MgO Formula (1)
in the formula, M 1 being at least one tertiary group element selected from Y and Tb;
M 2 being an alkali metal selected from Li, Na, and K; and
0<a<2, 0<b<2, 0≦c<1, 0.001≦d≦0.06, 0≦e≦0.06, 0.025≦x≦0.05, and 3.7≦f≦4.1 being set.
2. The fluorescent material according to claim 1 , wherein the fluorescent material has an external quantum efficiency of 66% or more when being excited by excitation light having a wavelength of 400 nm.
3. A light-emitting device comprising:
the fluorescent material according to claim 1 ; and
a light source irradiating the fluorescent material with excitation light to cause the fluorescent material to emit light.
4. The fluorescent material according to claim 1 , wherein a content of M 1 is 500 to 16000 ppm based on mass standard.
5. The fluorescent material according to claim 4 , wherein the fluorescent material has an external quantum efficiency of 66% or more when being excited by excitation light having a wavelength of 400 nm.
6. The fluorescent material according to claim 1 , wherein x is 0.025≦x≦0.03.
7. The fluorescent material according to claim 6 , wherein the fluorescent material has an external quantum efficiency of 66% or more when being excited by excitation light having a wavelength of 400 nm.