尺寸效应对Er3+掺杂纳米Y2O3的发光特性的影响

采用燃烧法制备了不同尺寸的Er³⁺掺杂Y₂O₃粉体材料，研究了尺寸效应对Er³⁺掺杂纳米Y₂O₃材料发光特性的影响.光声光谱显示，对于不同晶粒尺寸的样品，Er³⁺离子光声峰位置几乎保持不变.这表明小尺寸效应对稀土离子能级位置影响很小.对488nm激光激发下的发射谱的分析发现，随着样品颗粒尺寸的减小，4S_3/2能级和关键词： 3+离子')" href="#">Er³⁺离子 纳米 发光 能量传递

Size dependent luminescence properties of Er3+ doped nano-crystalline Y2O3

Er³⁺ doped Y₂O₃ nano-crystals with different size are prepared using combustion method. Size effect on luminescence properties of Er³⁺ doped Y₂O₃ nano crystals are investigated. No shift of the absorption peak in the photo-acoustic spectra is observed with the decrease of the Y₂O₃particle size, indicating that the size induced energy shifts of the rare-earth levels are negligible. However, the emission spectra under 488nm excitation indicate that the ratio of the intensity of ⁴S_3/2→⁴I_15/2 transition to that of ²H_11/2→⁴I_15/2 decreases with the decrease of the particle size. It is believed that the rate of hypersensitive transition of ²H_11/2→⁴I_15/2 increases with the decrease of the particle size more quickly than that of transition of ⁴S_3/2→⁴I_15/2. The time dependence of the 554nm luminescence decay excited by 518nm reveals that the rate of up-converted energy transfer occurring between two Er³⁺ ions in ⁴S_3/2 state increases with the decrease of the particle size.