蓝光激发的Y3Al2Ga3O12:Ce3+,Ge4+绿色长余辉材料发光性能研究

The Luminescent Properties of Blue-Light Activated Y3Al2Ga3O12：Ce3+，Ge4+ Green Persistent Phosphor

摘要:

采用高温固相法合成了新型Y₃Al₂Ga₃O₁₂:Ce³⁺,Ge⁴⁺绿色长余辉材料，并对其光致发光性能、余辉性能和光色热稳定性能进行了研究。结果表明：Y₃Al₂Ga₃O₁₂:Ce³⁺,Ge⁴⁺绿色长余辉材料在320—490 nm范围的宽带吸收与蓝光LED芯片相匹配，其发射光谱为位于450—650 nm范围的宽发射带，对应于Ce³⁺的5d-4f跃迁；Y₃Al₂Ga₃O₁₂:Ce³⁺,Ge⁴⁺的内量子效率可以达到83.28%，τ₈₀值约为12 s，远大于交流LED对于内量子效率>60%和τ₈₀>0.4 ms的要求；在423 K前，Y₃Al₂Ga₃O₁₂:Ce³⁺,Ge⁴⁺具有良好的光色稳定性。以上结果表明，Y₃Al₂Ga₃O₁₂:Ce³⁺,Ge⁴⁺是一种潜在的能被蓝光激发的交流LED用绿色长余辉材料。

Abstract:

A novel green persistent phosphor Y₃Al₂Ga₃O₁₂：Ce³⁺，Ge⁴⁺wassynthesized by high-temperature solid-state reaction. The prepared phosphor has broad absorption band in the range of 320—490 nm which matches well with the emission of blue LED chip. The broad emission band in 450—650 nm of the phosphor is assigned to the 5d-4f transitions of Ce³⁺. The internal quantum efficiency （IQE） and τ₈₀ of Y₃Al₂Ga₃O₁₂：Ce³⁺，Ge⁴⁺phosphor is 83.28% and 12 s， which are much larger than the requirement of alternating current LED （AC-LED） for IQE and τ₈₀ （IQE>60% and τ₈₀>0.4 ms）. Moreover， Y₃Al₂Ga₃O₁₂：Ce³⁺，Ge⁴⁺ phosphor has good light and color stability before 150 ℃. All the above results prove that green persistent phosphor Y₃Al₂Ga₃O₁₂：Ce³⁺，Ge⁴⁺ might be a promising candidate applicable in AC-LED.