白光LED用单一基质Ca10(Si2O7)3Cl2:Eu2+,Mn2+ 白色发光材料特性研究

采用高温固相法制备了单一基质Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺白色发光材料, 研究发现材料适于近紫外光激发, 发射高亮度的白色光. Eu²⁺发射中心形成峰值为426和523 nm的特征宽谱, 通过Eu²⁺向Mn²⁺的能量传递, 形成了峰值为585 nm的宽谱发射; 红、绿、蓝三色发射带叠加后, 在同一基质中实现了白光发射. 利用Dexter电多极相互作用的能量传递公式, 得出Ca₁₀(Si₂O₇)₃Cl₂中Eu²⁺对Mn²⁺的能量传递属于电偶极-电偶极相互作用引起的共振能量传递. 利用InGaN管芯(370 nm)激发Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺材料, 获得了很好的白光发射, 测得的色坐标为(x = 0.323, y = 0.327), 色温为5664 K, 显色指数为85%.

Luminescence characteristics of the single host white emitting Ca10(Si2O7)3Cl2:Eu2+,Mn2+ phosphor for white LED

The single host white emitting Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺ phosphor was synthesized by high temperature solid state reaction method, and the luminescence characteristics were investigated. The results show that Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺ phosphor exhibits three emission at 426, 523 and 585 nm. The 426 and 523 nm emission originates from the transition 5d?4f of Eu²⁺ that occupies the two Ca²⁺ sites in Ca₁₀(Si₂O₇)₃Cl₂, while the 585 nm emission is attributed to the energy transfer from Eu²⁺ to Mn²⁺. The white light can be obtained by mixing the three emission of blue (426 nm), green (523 nm) and red (585 nm) in the single host. According to the Dexter’ energy transfer formula of multipolar interaction, the energy transfer between Eu²⁺ and Mn²⁺ is due to the electric dipole-dipole interaction of the resonance transfer. The relative emission spectrum of the InGaN-based Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺ LED was investigated, and the CIE chromaticity is (x=0.323, y=0.327). Therefore, Ca₁₀(Si₂O₇)₃Cl₂:Eu²⁺,Mn²⁺ phosphor is a promising single host white emission phosphor for white LED.