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Abstract By employing the solvothermal in situ N -alkylation of organic bases with alcohol molecules, four new organically templated iodometallates as [L1][Ag 2 I 4 ] (L12+ = 1,1,4,4-tetramethyl-1λ4,4λ4-piperazinium) 1 , [L2] 1.5 [AgI 4 ] (L22+ = 1,4-dibenzyl-1λ4,4λ4-diazabicyclo[2.2.2]octanium) 2 , [L2] 1.5 [CuI 4 ] 3 and [L3][CuI 3 ] (L32+ = 4,4′-bis(3-methyl-1H-3λ4-imidazol-1-yl)-1,1′-biphenylium) 4 were obtained. In 1 , the in situ substitution and N-alkylation of 1,4-bis(pyridin-4-ylmethyl)piperazine (L1') with CH 3 OH has occurred, producing L12+. Templated by L12+, Ag+ and I- aggregate into a chained iodoargentate, which can be described as a linear arrangement of AgI 4 tedrahedra by sharing the edges. 2 and 3 are isostructural. In 2 and 3 , the in situ N -alkylation of 1,4-diazabicyclo[2,2,2]octane (L2') with phenylmethanol has occurred, generating L22+. Templated by L22+, Ag+ (or Cu+) and I- aggregate into a mononuclear iodometallate with a tetrahedral structure. In 4 , the in situ N -alkylation of 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L3') with CH 3 OH has occurred, creating L32+. Templating by L32+, Cu+ and I- aggregate into a mononuclear iodocuprate(I) with a planar trigonal structure. The photoluminescence analysis reveals that (i) at the room temperature, only 1 emits light (λ em = 550 nm); (ii) at the low temperature, 4 is found to possess the photoluminescence property (λ em = 546 nm at 77 K) with a ms-grade lifetime (τ = 4.915 ms). Graphical abstract By employing solvothermal in situ N -alkylation of organic bases with alcohol molecules, four new organically templated iodometallate(I) were obtained, and their photoluminescence properties were investigated. fx1 Highlights • Four new organically templated iodometallates(I) (M+ = Ag+, Cu+) are reported; • In situ N -alkylation of 1,4-diazabicyclo[2,2,2]octane with phenylmethanol is investigated for the first time; • In situ N -alkylation of 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl with alcohol molecules is investigated for the first time; • Their photoluminescence properties at different temperature are investigated. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this work is to develop a single-phase phosphor emitting white light under the excitation of near UV light, targeted at the possible application in white light emitting diodes. Our rationale is to employ a host containing noncentrosymmetric coordination sites for rare earth, therefore the f - f absorptions in the near UV range could be enhanced. Indeed, YGa 3 (BO 3) 4 is such a host where Y3+ is in a twisted triangular prism and could be substituted by various rare earth elements. The photoluminescence of Dy3+ and Tm3+ were investigated in Y 1- x Dy x Ga 3 (BO 3) 4 (0 ≤ x ≤ 0.10) and Y 1- y Tm y Ga 3 (BO 3) 4 (0.01 ≤ y ≤ 0.10), whose phase purity was confirmed by powder X-ray diffraction. Dy3+ emits yellowish white light and Tm3+ emits blue light under their respective f - f excitations (350 and 358 nm). The optimal concentrations in the singly-doped phosphors are 7 and 3 atom%, respectively. When co-doping Dy3+ and Tm3+ in YGa 3 (BO 3) 4 , there was no energy transfer between them. Eventually, a white light emission could be obtained with the CIE coordinates of (0.325, 0.329) in Y 0.91 Dy 0.07 Tm 0.02 Ga 3 (BO 3) 4 under the excitation of 364 nm. Graphical abstract Dy3+ and Tm3+ singly and co-doped YGa 3 (BO 3) 4 were synthesized by solid state reactions. Rietveld refinements confirmed that Dy3+ and Tm3+ replace Y3+ and locate in a triangular prism environment, which is beneficial for their f - f absorptions in near UV range. Since there is no energy transfer, tuning the content of Dy3+ and Tm3+ leads to the white emission with the CIE coordinate of (0.325, 0.329). fx1 Highlights • Structural refinements confirmed Dy3+/Tm3+ locates at the Y3+ site in YGa 3 (BO 3) 4. • Dy3+ and Tm3+ emit yellowish white and blue light in YGa 3 (BO 3) 4 , respectively. • The optimal concentration for Dy3+ is 7 atom% in Y 1- x Dy x Ga 3 (BO 3) 4. • The optimal concentration for Tm3+ is 3 atom% in Y 1- y Tm y Ga 3 (BO 3) 4. • Near UV excited white emission can be obtained in Y 0.91 Dy 0.07 Tm 0.02 Ga 3 (BO 3) 4. [ABSTRACT FROM AUTHOR]

The hydro(solvo)thermal reactions of CuI with diverse bisimidazole molecules were investigated, affording five new copper(I) iodides [Cu 4 I 4 (L1) 2 ] (L1=1,3-bis(2-methylimidazol-1-ylmethyl)benzene) 1 , [CuI(L2)] (L2=4,4′-bis(imidazolyl)biphenyl) 2 , [Cu 4 I 4 (L3)] (L3=1,3-bis(2-methylimidazol-1-yl)propane) 3 , [Cu 4 I 4 (L4) 2 ] (L4=1,4-bis(2-ethylimidazol-1-yl)butane) 4, and [Cu 4 I 4 (L5)] (L5=1,4-bis(1-imidazoly)benzene) 5 . X-ray single-crystal diffraction analysis reveals that (i) in 1 , a tetranuclear Cu-I cluster (stepped cubane) is observed, and the L1 molecule only acts as an ancillary ligand; (ii) in 2 , the L2 molecules extend the castellated Cu-I chains into a 2-D layer network with a certain thickness; (iii) in 2-D single-layer network of 3 , a 1-D Cu-I column is found, which can be viewed as a longitudinal packing of stepped Cu 4 I 4 cubanes; (vi) in 4 , the L4 molecules propagate the cubic Cu 4 I 4 cubanes into a 3-D 4-fold interpenetrated network with a cds topology; and (v) in 5 , the L5 molecules link the 1-D Cu-I ribbons into a 2-D single-layer network. The photoluminescence analysis indicates that 1 , 2 and 4 emit light (red light for 1 ; yellow light for 2 and 4 ), while 3 and 5 are not emissive. Their photoluminescence behaviors are confirmed to be related to the Cu···Cu interactions in the molecules. [ABSTRACT FROM AUTHOR]

Abstract: A series of full-color single-phased phosphors for white LEDs (W-LEDs), in the system (Y, Ln)2GeO5 (Ln=Tm, Tb, Eu), were prepared and their photoluminescence properties were characterized. The simultaneous incorporation of Eu3+, Tb3+ and Tm3+ ions in Y2GeO5 lattice can result in an integration of red, green, and blue emissions when being excited by ultraviolet light. Under excitation at 352nm, the color tones of the (Y0.95−x Tm0.01Tb x Eu0.04)2GeO5 phosphors change from cool white to warm white by increasing the concentration of Tb3+, while the intensities of Eu3+ emissions increase. Indeed, in the case of co-doped systems, a very efficient energy that transfers from Tb3+ to Eu3+ occurs. The present phosphors can potentially be used for the high CRI and high luminous efficient white LEDs. [Copyright &y& Elsevier]

The discovery of phosphor with efficient red emission is a crucial step in the development of the white light-emitting diodes (wLEDs). Herein, based on the regulation of the W/Zn ratio, the Eu3+-activated ZnWO 4 -WO 3 ∙0.5H 2 O-WO 3 multiphase phosphor was designed successfully via the one-step hydrothermal treatment route. The effects of the W/Zn ratio on the phase structure, composition, morphology, luminescence property and lifetime of the obtained samples were systematically and comparatively investigated. The obtained product not only maintains the multi-wavelength excitation feature of ZnWO 4 :Eu3+ phosphor, but also sharply improves the characteristic emission intensity of Eu3+ ions. It is found that the WO 3 ∙0.5H 2 O crystal has a special 3D interconnected channel structure, which is a relatively much access to the chemical behavior and permits the ready insertion of part of Eu3+ ions, and this coordination environment can obtain strong pure red light emission. Further, the ZnWO 4 -WO 3 :Eu3+ phosphor obtained after dehydration treatment can be excited more efficiently in the deep-ultraviolet (DUV), near-ultraviolet (NUV) and blue light regions, and its quantum efficiencies reach 18%, 22% and 21.2%, respectively. Besides, it also exhibits better CIE chromaticity coordinate, higher color purity than commercial Y 2 O 2 S:Eu3+ phosphor. Therefore, the ZnWO 4 -WO 3 :Eu3+ is promising for the application in red phosphor with different wavelengths for wLEDs. • The ZnWO 4 -WO 3 :Eu3+ multiphase phosphor was obtained by tailoring the W/Zn ratio. • The WO 3 ·0.5H 2 O with 3D interconnected channel structure allows the insertion of Eu3+. • The ZnWO 4 -WO 3 :Eu3+ phosphor can be efficiently excited by multi-wavelength bands. • Meritorious CIE, QE and high color purity was obtained. [ABSTRACT FROM AUTHOR]