La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″(X′and X″stand for two identical or different halide ions F^-,Cl^-,and Br^-)is a new kind matrix of phosphors.X-ray analysis shows that these crystals belong to the apatite stru...La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″(X′and X″stand for two identical or different halide ions F^-,Cl^-,and Br^-)is a new kind matrix of phosphors.X-ray analysis shows that these crystals belong to the apatite structure of hexagonal system with a space group of p6_(3/m).Their lattice parameters have been obtained.Subsolidus phase relationship in the double halophosphate systems were determined by lattice parameter method.It has been proved that in the Br-Cl and F-Cl systems there exist complete and continuous solid solutions.In the F-Br sys- tem there appears a two phase region with the bromide composition 0.75<Br<1.25. The variation of emission intensity of Ce^(3+)with the change of halogen composition has been observed. Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in Ce^(3+)activated La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″crystals.The temperature dependence of the peak wavelength was determined.As temperature is raised,emission bands shift towards blue.展开更多
Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in cerium(3+)activated Sr_5(PO_4)_3Cl crystals.Luminescence properties of Ce^(3+) in Sr_5(PO_4)_3X(X=F,Cl, Br)have been studi...Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in cerium(3+)activated Sr_5(PO_4)_3Cl crystals.Luminescence properties of Ce^(3+) in Sr_5(PO_4)_3X(X=F,Cl, Br)have been studied.Meanwhile crystalline Sr_5(PO_4)_3Br and the subsolidus phase relationship of binary strontium halophosphate systems have been determined.展开更多
We have synthesized a series of single-composition emission Na_2Sr_2Al_2PO_4Cl_9:Ce^(3+) phosphor by traditional solid state reactions and novel combustion method. Formation of compound was confirmed by X-ray diffract...We have synthesized a series of single-composition emission Na_2Sr_2Al_2PO_4Cl_9:Ce^(3+) phosphor by traditional solid state reactions and novel combustion method. Formation of compound was confirmed by X-ray diffraction analysis. The photoluminescence(PL) emission spectra were observed at 376 nm when excited around 322 nm for the various concentrations in both cases. The PL emission spectra of phosphors showed strong Ce^(3+)emission due to the 5d → 4f transition of Ce^(3+)ions. The Ce^(3+)emission intensity in Na_2Sr_2Al_2PO_4Cl_9:Ce^(3+) prepared by combustion was higher than that of solid state reactions.展开更多
文摘La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″(X′and X″stand for two identical or different halide ions F^-,Cl^-,and Br^-)is a new kind matrix of phosphors.X-ray analysis shows that these crystals belong to the apatite structure of hexagonal system with a space group of p6_(3/m).Their lattice parameters have been obtained.Subsolidus phase relationship in the double halophosphate systems were determined by lattice parameter method.It has been proved that in the Br-Cl and F-Cl systems there exist complete and continuous solid solutions.In the F-Br sys- tem there appears a two phase region with the bromide composition 0.75<Br<1.25. The variation of emission intensity of Ce^(3+)with the change of halogen composition has been observed. Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in Ce^(3+)activated La_(1.5)Sr_(7.0)Na_(1.5)(PO_4)_6X′X″crystals.The temperature dependence of the peak wavelength was determined.As temperature is raised,emission bands shift towards blue.
基金Project supported by National Natural Science Foundation of China
文摘Fluorescence spectroscopic study unraveled that there exist two types of luminescent center in cerium(3+)activated Sr_5(PO_4)_3Cl crystals.Luminescence properties of Ce^(3+) in Sr_5(PO_4)_3X(X=F,Cl, Br)have been studied.Meanwhile crystalline Sr_5(PO_4)_3Br and the subsolidus phase relationship of binary strontium halophosphate systems have been determined.
文摘We have synthesized a series of single-composition emission Na_2Sr_2Al_2PO_4Cl_9:Ce^(3+) phosphor by traditional solid state reactions and novel combustion method. Formation of compound was confirmed by X-ray diffraction analysis. The photoluminescence(PL) emission spectra were observed at 376 nm when excited around 322 nm for the various concentrations in both cases. The PL emission spectra of phosphors showed strong Ce^(3+)emission due to the 5d → 4f transition of Ce^(3+)ions. The Ce^(3+)emission intensity in Na_2Sr_2Al_2PO_4Cl_9:Ce^(3+) prepared by combustion was higher than that of solid state reactions.
