Nanoscale
·
2017
·Vol. 9
·期 17
·5718-5724
·
IF 7.367
Lei Lei,Shengjun Zhang,Han Xia,Ying Tian,Junjie Zhang,Shiqing Xu
Developing multicolor-emitting materials has significant value in many research fields such as displays, bioimaging, and information storage. The widely adopted strategies to realize multicolor emission are tuning the material composition, phase, and size. Herein, the emission color was continuously controlled from yellow to pink by simply changing the excitation wavelength from 254 nm to 365 nm for Tb3+/Eu3+ co-doped Gd2O2S NCs. The Gd2O2S NCs with different morphologies, including nanoplate with various sizes and flower-like, were successfully prepared by seed-mediated, Na+/Y3+ co-doped, and S concentration-tuned methods. The results indicated that Na+ ions greatly promote the growth of Gd2O2S NCs and Y3+ ions have an impact on their shape. Moreover, the PL intensity of the 2%Eu-doped flower-like Na/Y:Gd2O2S (F-NYG) NCs decreased by about 24.7%, 6.8%, and 5.1% under 254 nm, 316 nm, and 348 nm excitation, respectively; this is due to less non-radiative relaxation paths above the excited state of Eu3+:5D0 at longer excitation wavelength, which result in a decreased degree of the PL intensity reduction.
研究领域:
材料科学
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纳米技术
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光学材料
·
生物成像
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2020
·Vol. 10
·期 9
·1639
·
IF 4.324
Zhigang Sun,Bin Lu,Guiping Ren,Hongbing Chen
A translucent Gd2O2S:Pr ceramic scintillator with an in-line transmittance of ~31% at 512 nm was successfully fabricated by argon-controlled sintering. The starting precipitation precursor was obtained by a chemical precipitation route at 80 °C using ammonia solution as the precipitate, followed by reduction at 1000 °C under flowing hydrogen to produce a sphere-like Gd2O2S:Pr powder with an average particle size of ~95 nm. The Gd2O2S:Pr phosphor particle exhibits the characteristic green emission from3P0,1→3H4transitions of Pr3+at 512 nm upon UV excitation into a broad excitation band at 285–335 nm arising from 4f2→4f5dtransition of Pr3+. Increasing Pr3+concentrations induce two redshifts for the two band centers of 4f2→4f5dtransition and lattice absorption on photoluminescence excitation spectra. The optimum concentration of Pr3+is 0.5 at.%, and the luminescence quenching type is dominated by exchange interaction. The X-ray excited luminescence spectrum of the Gd2O2S:Pr ceramic is similar to the photoluminescence behavior of its particle. The phosphor powder and the ceramic scintillator have similar lifetimes of 2.93–2.99 μs, while the bulk material has rather higher external quantum efficiency (~37.8%) than the powder form (~27.2%).Keywords:Gd2O2S;Pr3+doping;ceramic scintillator;phosphor powder
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Aggregate
·
2023
·Vol. 4
·期 6
·e387
·
IF 18.8
Dengfeng Yang,Wei Zheng,Ping Huang,Meiran Zhang,Wei Zhang,Zhiqing Shao,Wen Zhang,Xiaodong Yi,Xueyuan Chen
Lanthanide (Ln 3+ ) oxysulfide nanocrystals (NCs) have great prospect in many advanced technologies; however, they suffer from a low photoluminescence efficiency due to the volatility of sulfur and deleterious surface quenching effect. Herein, we report a novel sandwiched luminescent heterostructure based on Ln 3+ -doped Gd 2 O 2 S@NaYF 4 core/shell NCs with tunable sulfur content in the sandwich layer. By means of Eu 3+ as the sensitive structural probes, we unravel the ligand-mediated structure control of the NCs from Gd 2 O 3 : Ln 3+ @NaYF 4 to Gd 2 O 2 S: Ln 3+ @NaYF 4 with tailored S 2– deficiency. Such a sandwich-type core/shell heterostructure enables us to achieve efficient and multicolor downshifting and upconversion luminescence (UCL), with up to 208.8 folds of enhancement in UCL intensity as compared to that of their core-only counterparts. These findings provide a general approach for the controlled synthesis of lanthanide oxysulfide@fluoride heterostructure, which offers a new way for the materials design towards diverse emerging applications.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 106
·86885-86890
·
IF 3.84
Hechun Lin,Qianqian Luo,Wen-Yi Tong,Chunli Jiang,Rong Huang,Hui Peng,Lai-Chang Zhang,Jadranka Travas-Sejdic,Chun-Gang Duan
EuS and Gd2O2S nanocrystals with narrow size distribution are synthesized in high yields by the thermal decomposition of Eu(oleate)3 or Gd(oleate)3 in oleylamine using CS2 as the sulfur source. The dimensionalities of these nanocrystals can be facilely tuned by the addition of 1-dodecanethiol. The morphologies and crystal structures of EuS and Gd2O2S nanocrystals are characterized by TEM and XRD. The magnetic properties of the obtained nanocrystals are also investigated. The experimental results illustrate that CS2 is an effective sulfur source for the preparation of metal sulfide and lanthanide oxysulfide semiconductor nanocrystals.
研究领域:
材料科学
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纳米科技
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无机化学
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半导体物理
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磁性材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）