SUN Yue-sheng, QU Yun, XIAO Jian-mou, CHEN Da. Luminescent Properties of Small-sized Red Phosphor Y<sub>2</sub>O<sub>3</sub>:Eu<sup>3+</sup> Synthesized by Oxalic Acid Precipitation Method[J]. Chinese Journal of Luminescence, 2004,25(4): 359-364
SUN Yue-sheng, QU Yun, XIAO Jian-mou, CHEN Da. Luminescent Properties of Small-sized Red Phosphor Y<sub>2</sub>O<sub>3</sub>:Eu<sup>3+</sup> Synthesized by Oxalic Acid Precipitation Method[J]. Chinese Journal of Luminescence, 2004,25(4): 359-364DOI:
草酸沉淀法制备细颗粒红色荧光粉Y2O3:Eu3+的发光特性
摘要
对草酸作为沉淀剂制备的细颗粒红色荧光粉Y
2
O
3
:Eu
3+
进行结构和发光特性研究
结果表明:其一次粒径为20~30nm
团聚尺寸
D
50
=0.53μm。该荧光粉最大激发峰位于252.2nm
较微米级荧光粉233nm红移了19.2nm;最大的发射峰位于612nm
与微米级的相比几乎没有差别。Eu
3+
离子的掺入构成了发光中心
其最佳掺杂的质量分数为9%
荧光粉发光的猝灭浓度由微米级的6%提高到9%。由于纳米晶存在表面缺陷和悬挂键
其亮度约为微米晶的70%左右
随着团聚尺寸的增加、煅烧温度的提高和助熔剂的加入
荧光粉的发光强度增大。包膜能部分消除表面缺陷和悬挂键
提高发光亮度。荧光粉的色坐标为
x
=0.6479
y
=0.3442。
Abstract
Y
2
O
3
:Eu
3+
is a red phosphor with good property.It is usually synthesized by high temperature solid state method.The particle size of the phosphor prepared by this method is lager
so it must be milled when used.The oxalic acid precipitation method was developed to synthesize non-grinded and small-size red phosphor in our experiment.Firstly
the mixture of Y
2
O
3
and Eu
2
O
3
was dissolved in nitric acid in certain proportion.Secondly
the prepared oxalic acid solution was placed in a reactor and at the same time a little surfactant was added in it.When the reaction temperature was controlled to be certain value
the nitric acid solution of Y
Eu was added.Afterwards the precipitation formed and then washed
filtrated
dried and calcined to become white Y
2
O
3
:Eu
3+
power.The Luminescent properties of the phosphor were mainly studied .The result shows that the particle diameter is 20~30nm.The agglomerate size is D
50
=0.53μm.The particle is fine and the granularity distribution displays a narrow and normal distribution.The maximum excitation spectrum of the phosphor peaks at
λ
=252.2nm
red shift 19.2nm compared with micro-Y
2
O
3
:Eu
3+
.The maximum emission spectrum peaks at
λ
=612nm under 254nm excitation.Compared with the ordinary power of Y
2
O
3
:Eu
3+
the emission spectrum of the phosphor appears unchangeable.The luminescent intensity increases with growing of agglomerate size.The addition of Eu
3+
can constitute luminescent centers when Y
2
O
3
as basic particle and Eu
3+
as activator in Y
2
O
3
:Eu
3+
.The less the amount of the added Eu
3+
is
the lower the luminescent brightness of the phosphor is.The critical concentration of Eu
3+
increases from 6% for micro-Y
2
O
3
:Eu
3+
to 9% for nano-Y
2
O
3
:Eu
3+
.The phosphor shows a relative luminescent brightness about 70% of that of the micro-Y
2
O
3
:Eu
3+
because of the existence of hanging-bonds and defects on the surface of nano-Y
2
O
3
:Eu
3+
particles.The phosphor particle was increased and the defects on the surface of the phosphor was decreased at high temperature
so luminescent brightness of the phosphors was increased.Adding assist melting agent can decrease sintering temperature and increase D
50
of the phosphor
and the brightness of the phosphor increased
too.Coating-process on phosphor can dispel defact and increase brightness.The luminescent chromatic coordinate parameters of the phosphor are