The Effect of Nd³⁺ Concentration on Upconversion Luminescence in Yb³⁺/Tm³⁺/Nd³⁺ Tripledoped β-NaGdF₄ Nanocrystals

Abstract

Nd³⁺-doped NaGdF₄: Yb, Tm nanocrystals were synthesized by an improved high-temperature thermal decomposition method, and the effects of doping concentrations on the crystal structure, phase composition, and upconverted fluorescence intensity were also investigated. The results reveal that the introduction of Nd³⁺ ions does not cause the transformation of the crystal phase, but induce the change of the unit cell parameters. Meanwhile, the fluorescence intensity of the synthesized nanocrystals when co-doped with 3 mol% Nd³⁺ is the strongest under the excitation of 980 nm laser, which is 3.9 times that of the Nd³⁺-free doped nanoparticles, and the average size is 62.9 nm. And it is located in the blue area of the CIE coordinate diagram, and the corresponding color purity is 91.81% under the same experimental conditions. The resulting nanocrystals show the potential as excellent fluorescence labeling and in vivo imaging probes.

Keywords

upconversion / Nd³⁺ doped / fluorescence intensity / β-NaGdF₄

References

[1] Xu F, Zhao Y, Hu M, et al. Lanthanide-doped Core-Shell Nanoparticles as a Multimodality Platform for Imaging and Photodynamic Therapy [J]. Chem. Commun. (Camb), 2018, 54(68): 9525-9528.

[2] Wen S, Zhou J, Zheng K, et al. Advances in Highly Doped Upconversion Nanoparticles[J]. Nat. Commun., 2018, 9(1): 2415

[3] Chen B, Wang F. Emerging Frontiers of Upconversion Nanoparticles [J]. Trends in Chemistry, 2020, 2(5): 427-439.

[4] Demina P A, Sholina N V, Akasov R A, et al. A Versatile Platform for Bioimaging Based on Colonic Acid-Decorated Upconversion Nanoparticles[J]. Biomater. Sci., 2020, 8(16): 4570-4580.

[5] Du P, Huang X, Yu J S. Yb³⁺-Concentration Dependent Upconversion Luminescence and Temperature Sensing Behavior in Yb³⁺/Er³⁺ Co-doped Gd₂MoO₆ Nanocrystals Prepared by a Facile Citric-Assisted Sol-Gel Method[J]. Inorganic Chemistry Frontiers, 2017, 4(12): 1987-1995.

[6] Wang J, Wei T, Li X, et al. Near-Infrared-Light-Mediated Imaging of Latent Fingerprints Based on Molecular Recognition[J]. Angew Chem. Int. Ed. Engl., 2014, 53(6): 1616-1620.

[7] Ye J, Jiang J, Zhou Z, et al. Near-Infrared Light and Upconversion Nanoparticle Defined Nitric Oxide-Based Osteoporosis Targeting Therapy[J]. ACS Nano, 2021: 13692–13702

[8] He M, Pang X, Liu X, et al. Monodisperse Dual-Functional Upconversion Nanoparticles Enabled Near-Infrared Organolead Halide Perovskite Solar Cells[J]. Angew Chem. Int. Ed. Engl., 2016, 55(13): 4280-4284.

[9] Zhang C, Li X, Liu M, et al. Dual-Wavelength Stimuli and Green Emission Response in Lanthanide Doped Nanoparticles for Anti-Counterfeiting[J]. Journal of Alloys and Compounds, 2020, 836: 155487.

[10] Ya-Wen Z, Rui S, Li-Ping Y, et al. Single-Crystalline and Monodisperse LaF₃ Triangular Nanoplates from a Single-Source Precursor[J]. Journal of the American Chemical Society, 2005, 127(10): 3260-3261.

[11] Bednarkiewicz A, Wawrzynczyk D, Nyk M, et al. Synthesis and Spectral Properties of Colloidal Nd³⁺ Doped NaYF₄ Nanocrystals[J]. Optical Materials, 2011, 33(10): 1481-1486.

[12] Jiao M, Jing L, Liu C, et al. Differently Sized Magnetic/Upconversion Luminescent NaGdF₄:Yb,Er Nanocrystals: Flow Synthesis and Solvent Effects[J]. Chem. Commun. (Camb), 2016, 52(34): 5872-5875.

[13] Zhu Q, Sun T, Chung M N, et al. Yb⁽³⁺⁾-Sensitized Upconversion and Downshifting Luminescence in Nd⁽³⁺⁾ Ions through Energy Migration [J]. Dalton. Trans., 2018, 47(26): 8581-8584.

[14] Han S, Deng R, Xie X, et al. Enhancing Luminescence in Lanthanide-Doped Upconversion Nanoparticles[J]. Angew Chem. Int. Ed. Engl., 2014, 53(44): 11702-11715.

[15] Ren Y, He S, Huttad L, et al. An NIR-II/MR Dual Modal Nanoprobe for Liver Cancer Imaging[J]. Nanoscale, 2020, 12(21): 11510-11517.

[16] Okubo K, Takeda R, Murayama S, et al. Size-Controlled Bimodal in Vivo Nanoprobes as Near-Infrared Phosphors and Positive Contrast Agents for Magnetic Resonance Imaging[J]. Sci. Technol. Adv. Mater., 2021, 22(1): 160-172.

[17] Lyu L, Cheong H, Ai X, et al. Near-Infrared Light-Mediated Rare-Earth Nanocrystals: Recent Advances in Improving Photon Conversion and Alleviating the Thermal Effect[J]. Npg Asia Materials, 2018, 10: 685-702.

[18] Zhao C, Kong X, Liu X, et al. Li⁺ Ion Doping: an Approach for Improving the Crystallinity and Upconversion Emissions of NaYF₄:Yb³⁺, Tm³⁺ Nanoparticles[J]. Nanoscale, 2013, 5(17): 8084-8089.

[19] Zhao S, Xia D, Zhao R, et al. Tuning the Morphology, Luminescence and Magnetic Properties of Hexagonal-Phase NaGdF₄: Yb, Er Nanocrystals via Altering the Addition Sequence of the Precursors[J]. Nanotechnology, 2017, 28(1): 015601

[20] Li J, Jia Y, Xu Y, et al. In Situ Epitaxial Growth of GdF3 on NaGdF₄: Yb, Er Nanoparticles[J]. Inorganic Chemistry Frontiers, 2017, 4(12): 2119-2125.

[21] Su Q, Han S, Xie X, et al. The Effect of Surface Coating on Energy Migration-Mediated Upconversion[J]. J. Am. Chem. Soc., 2012, 134(51): 20849-20857.

[22] Zhang X, Zhao Z, Zhang X, et al. Magnetic and Optical Properties of NaGdF₄:Nd³⁺, Yb³⁺, Tm³⁺ Nanocrystals with Upconversion/Downconversion Luminescence from Visible to the Near-Infrared Second Window[J]. Nano Research, 2014, 8(2): 636-648.

[23] Chen G, Agren H, Ohulchanskyy T Y, et al. Light Upconverting Core-Shell Nanostructures: Nanophotonic Control for Emerging Applications[J]. Chem. Soc. Rev., 2015, 44(6): 1680-1713.

[24] Marconi Da Silva M D, Linhares H, Felipe Henriques Librantz A, Gomes L, et al. Energy Transfer Rates and Population Inversion Investigation of ¹ G ₄ And ¹ D ₂ Excited States of Tm³⁺ in Yb:Tm:Nd:KY₃F₁₀ Crystals[J]. Journal of Applied Physics, 2011, 109(8): 44

[25] Du P, Wang L, Yu J S. Luminescence Properties and Energy Eransfer Behavior of Single-Component NaY(WO₄)₂:Tm³⁺/Dy³⁺/Eu³⁺ Phosphors for Ultraviolet-Excited White Light-Emitting Diodes[J]. Journal of Alloys and Compounds, 2016, 673: 426-432.