Er3+单掺、Er3+/Yb3+共掺杂Ca12Al14O32F2的 制备及上转换发光性质

利用高温固相法成功制备了Er~(3+)单掺、Er~(3+)/Yb~(3+)共掺杂Ca_(12)Al_(14)O_(32)F_2上转换发光样品。在980 nm激光激发下,Er~(3+)单掺和Er~(3+)/Yb~(3+)共掺杂样品均呈现出较强的绿光(528,549 nm)和较弱的红光(655 nm)发射,分别归因于Er~(3+)离子的~2H_(11/2),~4S_(3/2)→~4I_(15/2)和~4F_(9/2)→~4I_(15/2)能级跃迁。随着Er离子浓度的增加,单掺杂样品上转换发光强度先增大后减小,最佳掺杂浓度为0.8%。共掺杂Yb~(3+)后,Er~(3+)的发光强度明显增大。还原气氛下合成的样品上转换发光强度增大约两倍,可能和笼中阴离子基团变化有关。发光强度和激发光功率的关系表明所得上转换发射为双光子吸收过程,借助Er~(3+)-Yb~(3+)体系能级结构详细讨论了上转换发射的跃迁机制。

Synthesis and Luminescence Properties of Er3+ Doped and Er3+-Yb3+ Co-doped Ca12Al14O32F2

Er³⁺ doped and Er³⁺-Yb³⁺ co-doped Ca₁₂Al₁₄O₃₂F₂ were synthesized by solid-state reaction method at 1 250℃ and the upconversion luminescence (UCL) properties of the phosphor were studied under 980 nm excitation. The phosphor exhibits green (549 nm) and red (655 nm) emission, which corresponding to ⁴S_3/2, ²H_11/2→⁴I_15/2 and ⁴F_9/2→⁴I_15/2 transitions of Er³⁺ respectively. The UCL intensity of the single doped sample increased firstly and then decreased with the increasing Er³⁺ concentration and the optimum concentration is 0.8%. The UCL intensity of Ca₁₂Al₁₄O₃₂F₂:Er³⁺, Yb³⁺ prepared in reducing atmosphere is enhanced by 2 times, which might be due to the encaged ions. The dependence of the UCL intensity on excitation powder proves that the observed emissions are obtained via two absorption processes. The transition mechanism of phosphor excitation under 980 nm is discussed in detail.