用于白光LED的高亮度蓝白色荧光粉Ca2SiO3Cl2：Eu2+的发光性质

采用固相法在较低温度下合成了Eu²⁺激活的Ca₂SiO₃Cl₂高亮度蓝白色发光材料,并对其发光性质进行了研究。其发射光谱由两个谱带组成,峰值分别位于420,498nm处,归结为Ca₂SiO₃Cl₂晶体中占据两种不同Ca²⁺格位的Eu²⁺离子的5d→4f跃迁发射。改变Eu²⁺浓度,可以使样品的发光在蓝白色和绿白色之间变化。当Eu²⁺浓度为0.005mol^-1时,样品呈现很亮的蓝白色发光。两个发射峰的激发光谱均分布在250~410nm的波长范围内,峰值分别位于333,369nm处。Ca₂SiO₃Cl₂:Eu²⁺可被InGaN管芯产生的近紫外辐射有效激发,是一种性能良好的白光LED用单一基质蓝白色荧光粉。

Luminescence Properties of Bright Ca2SiO3Cl2：Eu2+ for White LEDs

The intense blue-white emitting phosphors Ca₂SiO₃Cl₂:Eu²⁺ were synthesized by traditional high temperature solid state reaction method,and their luminescence properties were studied.The results indicate that the emission band consists of two peaks located at 420 and 498 nm,respectively.The two peaks are(originated) from the transition 5d→4f of Eu²⁺ ions that occupy the two Ca²⁺ sites in the crystal of Ca₂SiO₃Cl₂.The emitting of Ca₂SiO₃Cl₂:Eu²⁺ can be changed from blue-white to green-white color by adjusting the Eu²⁺ concentration.When the Eu²⁺ concentration is 0.005 mol^-1,the sample presents intense blue-white emitting.The excitation spectra of the two emissions both extend from 250 nm to 410 nm,and their peaks positioned(around) 333 nm and 369 nm,respectively.Ca₂SiO₃Cl₂:Eu²⁺ is a superior single-phase blue-white phosphor with low-cost and high brightness for white LEDs,Ca₂SiO₃Cl₂:Eu²⁺ phosphor can be excitated by InGaN chip UV emission effectively.