The hyperfine red phosphors,NaEu(MoO4)2,were synthesized by hydrothermal and subsequent heat-treatment processes.The NaEu(MoO4)2 phosphors show regular elliptical morphologies,and the particle sizes of 0.25～0.3 μm.The excitation spectra located at short-wavelength UV region belong to the interweave broad charge transfer bands of Mo6+-O2-and Eu3+-O2-,and the three sharp lines around 395 nm,465 nm and 535 nm are ascribed to the Eu3+ 4f excitation transitions.All of the samples can be excited with near-UV 395 nm light and exhibit the characteristic red emission of Eu3+ 5D0→7F2transition.The relative red emission intensities of the optimum phosphors reach two-fold as compared with that of the commercial phosphors.The submicro-phosphors may be applied as red phosphors for white light emitting diodes.
The hydrothermal reaction of pyridine-3,4-dicarboxylic acid(pydcH2),4,4'-bipyridine and GdCl3.6H2O yield a novel gadolinium coordination polymer {[Gd2(pydc)2(μ3-OH)2(H2O)2].H2O}n(1).The compound was chara-cterized by elemental analysis,thermal analysis,IR spectra and single-crystal X-ray structure analysis.The crystal of the Gd(Ⅲ) complex belongs to triclinic system,space group P1 with:a=0.796 25(16) nm,b=0.944 46(19) nm,c=1.262 1(3) nm,α=76.50(3)°,β=84.95(3)°,γ=83.04(3)°,Z=2,V=0.914 4(3) nm3,Dc=2.669 g.cm-1,μ=7.269 mm-1,F(000)=692,and R1=0.033 3,wR2=0.062 3.The crystal structure revealed that compound 1 has a 2D layer structure incorporating 1D Gd-O-Gd double chain,and hydrogen bonding interactions result in the former of 3D supramolecular network structure.CCDC:669079.
