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1. Sensitization of Ln III (Ln = Eu, Tb, Tm) Ion Luminescence by Functionalized Polycarbonate-Based Materials and White Light Generation: Sensitization of Ln III (Ln = Eu, Tb, Tm) Ion Luminescence by Functionalized Polycarbonate-Based Materials and White Light Generation

   https://doi.org/10.1002/ejic.201700655  

   Tigaa, Rodney A. ; Aerken, Xuekelaiti ; Fuchs, Alan ; de Bettencourt-Dias, Ana ( December 2017 , European Journal of Inorganic Chemistry)
2. High-Resolution X-ray Photoelectron Spectroscopy of Organometallic (C 5 H 4 SiMe 3 ) 3 Ln III and [(C 5 H 4 SiMe 3 ) 3 Ln II ] 1– Complexes (Ln = Sm, Eu, Gd, Tb)

   https://doi.org/10.1021/jacs.1c06980  

   Huh, Daniel N. ; Bruce, Jared P. ; Ganesh Balasubramani, Sree ; Ciccone, Sierra R. ; Furche, Filipp ; Hemminger, John C. ; Evans, William J. ( October 2021 , Journal of the American Chemical Society)
3. Luminescent Carbazole-Based Eu III and Yb III Complexes with a High Two-Photon Absorption Cross-Section Enable Viscosity Sensing in the Visible and Near IR with One- and Two-Photon Excitation

   https://doi.org/10.1021/acs.inorgchem.9b03561  

   Monteiro, Jorge H. ; Fetto, Natalie R. ; Tucker, Matthew J. ; de Bettencourt-Dias, Ana ( March 2020 , Inorganic Chemistry)
4. Effect of the aromatic substituent on the para -position of pyridine-bis(oxazoline) sensitizers on the emission efficiency of their Eu III and Tb III complexes

   https://doi.org/10.1039/d0dt03135f  

   de Bettencourt-Dias, Ana ; Rossini, Jeffrey S. ; Sobrinho, Josiane A. ( December 2020 , Dalton Transactions)

   null (Ed.)

   Two efficient lanthanide ion sensitizers 2,6-bis(oxazoline)-4-phenyl-pyridine (PyboxPh, 1 ) and 2,6-bis(oxazoline)-4-thiophen-2-yl-pyridine (Pybox2Th, 2 ) were synthesized. 1 crystallizes in the monoclinic space group P 21/ c with cell parameters a = 16.3794(4) Å, b = 7.2856(2) Å, c = 11.7073(3) Å, β = 97.229(1)° and V = 1385.97(6) Å 3 . 2 crystallizes in the monoclinic space group P 21/ n with cell parameters a = 5.9472(2), b = 16.0747(6), c = 14.3716(5) Å, β = 93.503(1)° and V = 1371.35(8) Å 3 . Photophysical characterization of 1 shows that its triplet state energy is located at 22 250 cm −1 and efficient energy transfer is observed for Eu III and Tb III . Solutions of [Ln(PyboxPh) 3 ] 3+ in dichloromethane display an emission efficiency of 37.2% for LnEu and 24.0% for LnTb. The excited state lifetimes for Eu III and Tb III are 2.227 ms and 723 μs, respectively. The triplet state energy of 2 is located at 19 280 cm −1 and is therefore too low to efficiently sensitize Tb III emission. However, the sensitization of Eu III is effective, with an emission quantum yield of 14.5% and an excited state lifetime of 714 μs. This shows that the derivatization of the chelator is strongly influenced by the aromatic substituents on the para -position of the pyridine ring. New isostructural 1 : 1 complexes of PyboxPh with Eu III ( 3 ) and Tb III ( 4 ) were also isolated and crystallize in the triclinic space group P 1̄ with cell parameters a = 9.1845(2) Å, b = 10.3327(2) Å, c = 11.9654(2) Å, α = 98.419(1)°, β = 108.109(1)°, γ = 91.791(1)°, V = 1064.08(4) Å 3 and a = 7.8052(1) Å, b = 11.8910(1) Å, c = 14.2668(2) Å, α = 72.557(1)°, β = 86.355(1)°, γ = 77.223(1)°, V = 1231.95(3) Å 3 , respectively. 

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5. Optical properties of undoped, Eu 3+ doped and Li + co-doped Y 2 Hf 2 O 7 nanoparticles and polymer nanocomposite films

   https://doi.org/10.1039/c9qi01181a  

   Gupta, Santosh K. ; Zuniga, Jose P. ; Abdou, Maya ; Ghosh, P. S. ; Mao, Yuanbing ( January 2020 , Inorganic Chemistry Frontiers)

   Desirable phosphors for lighting, scintillation and composite films must have good light absorption properties, high concentration quenching, high quantum efficiency, a narrow color emission, and so forth. In this work, we first show that undoped yttrium hafnate Y 2 Hf 2 O 7 (YHO) nanoparticles (NPs) display dual blue and red bands after excitation using 330 nm light. Based on density functional theory (DFT) calculations, these two emission bands are correlated with the defect states arising in the band-gap region of YHO owing to the presence of neutral and charged oxygen defects. Once doped with Eu 3+ ions (YHOE), the YHO NPs show a bright red emission, a long excited state lifetime and stable color coordinates upon near-UV and X-ray excitation. Concentration quenching is active when Eu 3+ doping reaches 10 mol% with a critical distance of ∼4.43 Å. This phenomenon indicates a high Eu 3+ solubility within the YHO host and the absence of Eu 3+ clusters. More importantly, the optical performance of the YHOE NPs has been further improved by lithium co-doping. The origin of the emission, structural stability, and role of Li + -co-doping are explored both experimentally and theoretically. DFT calculation results demonstrate that Li + -co-doping increases the covalent character of the Eu 3+ –O 2− bonding in the EuO 8 polyhedra. Furthermore, the YHOE NPs have been dispersed into polyvinyl alcohol (PVA) to make transparent nanocomposite films, which show strong red emission under excitation at 270 and 393 nm. Overall, we demonstrate that the YHO NPs with Eu 3+ and (Eu 3+ /Li + ) doping have a high emission intensity and quantum efficiency under UV and X-ray excitation, which makes them suitable for use as phosphors, scintillators and transparent films for lighting, imaging and detection applications. 

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