摘要
利用高温固相法制备了BaGa_(2)O_(4)∶Cr^(3+),Sm^(3+)(BGO∶Cr,Sm)近红外长余辉发光(PersL)材料,考察了Sm^(3+)掺杂浓度和煅烧温度对BGO∶Cr,Sm晶体结构和发光性能的影响,初步探讨了近红外余辉发光机理。结果表明:当长余辉发光材料组成为BGO∶Cr0.06,Sm0.004且煅烧温度为1100℃时,可以获得高纯度的BGO∶Cr,Sm长余辉发光材料,其发射波长为734 nm。Cr^(3+)与Sm^(3+)共掺杂为应用于生物成像的BGO提供了优化策略,同时为开发长余辉发光材料提供了良好范例。
Objective Cr^(3+)-doped near-infrared(NIR)emitting persistent luminescence(PersL)materials with an emission range of 650-1000 nm are renewable by red light instead of ultraviolet(UV)light,which is highly promising for renewable tissue imaging in vivo and broad application prospects in biomedical diagnosis and treatment.We have recently reported a BaGa_(2)O_(4)∶Cr^(3+)(BGO∶Cr)NIR emitting PersL material with Cr^(3+)as the luminescent center and BaGa_(2)O_(4) as the matrix.The BGO∶Cr PersL material exhibited UV excitation,light-emitting diode(LED)light restimulation,ultra-long PersL for more than 6 days,and excellent capability for information storage.This study aims to develop BaGa_(2)O_(4)∶Cr^(3+),Sm^(3+)NIR emitting PersL materials with stronger luminescence intensity and longer emission wavelengths than BGO∶Cr PersL materials by co-doping BGO∶Cr PersL materials with Sm^(3+)ions for the development of medical multimodal imaging,medical detection probes,integrated diagnosis,and treatment probes.Methods In this study,BGO∶Cr,Sm PersL materials were synthesized using a high-temperature solid-state synthesis method.The effects of Sm^(3+)doping concentration and calcination temperature on the luminescent properties and crystal structure of BGO∶Cr,Sm PersL materials were investigated,and the NIR luminescence mechanism was discussed.The surface shape,element distribution mappings,and thermal stability of BGO∶Cr,Sm PersL materials were observed and analyzed.Results and Discussions In PersL material characterization,all X-ray diffraction peaks of the BGO∶Cr,Sm PersL materials were consistent with those of the BGO plane crystals(PDF 46-0415),the energy dispersive X-ray spectrometry spectra and element distribution mappings of BGO∶Cr,Sm PersL materials indicated the presence of Ba,Ga,O,Cr,and Sm elements,and transmission electron microscopy images show that the average particle length of the PersL materials is 1.61μm and the average width is 0.76μm(Fig.1).The BGO∶Cr,Sm PersL materials exhibit strong NIR luminescence at 734 nm,with the BGO∶Cr0.06,Sm0.004 sample exhibiting the highest luminous intensity.Furthermore,the PersL intensity of BGO∶Cr PersL materials was enhanced after co-doped with Sm^(3+)ion[Figs.2(a),(b)],and the afterglow time of the BGO∶Cr0.06,Sm0.004 PersL material is 131.61 s.According to the thermoluminescence measurements,the electron trap energy-level depth is estimated to be approximately 0.553 eV by the half-width method,showing that BGO∶Cr,Sm PersL materials are suitable for providing PersL for a long time at room temperature[Figs.2(d),(e)].A schematic energy diagram of the PersL mechanism shows that the NIR luminescence of BGO∶Cr,Sm is produced by the spin-forbidden ^(2)E(^(2)G)→^(4)A_(2)(^(4)F)transition of Cr^(3+)and that PersL is produced by the recombination of holes and charge carriers released from the trap after stopping UV irradiation[Fig.2(f)].Meanwhile,our studies have shown that BGO∶Cr,Sm PersL materials exhibit good thermal stability,and the maximum luminous intensity at 150℃shows their potential as raw materials for red LEDs(Fig.4).Finally,we found that BGO∶Cr,Sm PersL materials exhibit good crystallinity and NIR luminescence only when the calcination temperature reaches 1100°C(Fig.5).Conclusions In summary,BGO∶Cr,Sm PersL materials with an emission wavelength of 734 nm were prepared using a high-temperature solid-state synthesis method.The luminescence intensity reached the maximum when the composition of the PersL materials was BGO∶Cr0.06,Sm0.004,and the PersL intensity of BGO∶Cr was enhanced by Sm^(3+)doping.The calcination temperature has a significant effect on the luminescence properties and crystal structure of BGO∶Cr,Sm PersL materials.BGO∶Cr,Sm PersL materials with high purity can be obtained when the annealing temperature is 1100℃.The electron trap energy-level depth of BGO∶Cr,Sm PersL materials is approximately 0.553 eV when estimated using the half-width method.BGO∶Cr,Sm PersL materials exhibit strong and persistent luminescence by co-doping and have potential applications in night vision surveillance and medical imaging.
作者
杨倩婷
热萨莱提·伊敏
孙艳美
热娜古丽·阿不都热合曼
孙雪峰
杨通胜
Yang Qianting;Risalat Emin;Sun Yanmei;Renagul Abdurahman;Sun Xuefeng;Yang Tongsheng(Laboratory of Xinjiang Native Medicinal and Edible Plant Resources Chemistry,College of Chemistry and Environmental Science,Kashi University,Kashi 844006,Xinjiang,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2023年第6期38-46,共9页
Chinese Journal of Lasers
基金
国家自然科学基金(21867014)
喀什大学高层次人才科研启动经费项目(GCC18ZK-003)
喀什大学博士专项项目[(16)2579]。
