【摘要】 采用高温固态烧结方法制备了具有不同Mn⁴⁺离子掺杂浓度的Lu₂O₃∶x%Mn⁴⁺荧光粉。应用X射线衍射、荧光激发和发射光谱、X射线光电子能谱、扫描电子显微镜和发光动力学测量等手段研究了该荧光粉的微结构和发光特性与掺杂浓度的关系。实验结果表明,Mn⁴⁺离子可掺杂到Lu₂O₃基质晶格中,在252 nm激发下,可观察到位于695 nm和712 nm的近红外发射峰,其分别来源于Mn⁴⁺离子的2E→4A2和4T2→4A2的跃迁。当Mn⁴⁺掺杂浓度为0. 1%时,可获得最大的发光强度。通过优化热处理条件（在空气气氛、1400℃温度下热处理5 h）,可进一步提高Lu₂O₃∶0. 1%Mn⁴⁺荧光粉的近红外发光强度和余辉性能。实验发现,经热处理的Lu₂O₃∶0. 1%Mn⁴⁺样品中,Mn⁴⁺离子占据了Lu₂O₃基质中的S6和C2两种格位;具有较长寿命的近红外发光来自占据S6格位Mn⁴⁺离子的贡献,而具有较短寿命的近红外发光则来自占据C2格位Mn⁴⁺离子的贡献。实验表明,经高温热处理的近红外发射Lu₂O₃∶Mn⁴⁺材料余辉时间大于3 min,其在生物成像方面有潜在的应用前景。更多还原

【Abstract】 Novel near infrared（ NIR） emitting Lu₂O₃∶ x% Mn⁴⁺phosphors with different concentrations were prepared by a high temperature solid-state method. The dependences of the microstructural and luminescent properties of the phosphor on the Mn⁴⁺doping concentration were investigated by means of X-ray diffraction,excitation and emission spectra,X-ray photoelectron spectroscopy,scanning electron microscope and luminescence dynamics measurement. It is found that Mn⁴⁺can be doped into the Lu₂O₃ host and NIR emissions peaked at 695 nm and 712 nm,which originate from the2 E→4 A2 and4 T2→4 A2 transitions,respectively,can be observed upon 252 nm excitation. When the Mn⁴⁺doping concentration is 0. 1%,the strongest luminescent intensity can be reached. After the Lu₂O₃∶ 0. 1% Mn⁴⁺phosphor was annealed at 1400 ℃ in air for 5 h,its NIR emission intensity and afterglow performances were significantly improved. For the annealed Lu₂O₃∶ 0. 1% Mn⁴⁺phosphor,it is found that Mn⁴⁺occupy S6 and C2 sites in the Lu₂O₃ host. The NIR emission with longer lifetime comes from the contribution of Mn⁴⁺occupying S6 sites,while that with shorter lifetime comes from the contribution of Mn⁴⁺occupying C2 sites. The afterglow time of NIR emitting Lu₂O₃∶ Mn⁴⁺phosphor is more than 3 min,suggesting it has potential application in bioimaging.更多还原