Tb^(3+)-doped Ca_ x Sr_(1- x )WO_4 was prepared by solid state reaction and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belongs to tetragonal system, which is consistent...Tb^(3+)-doped Ca_ x Sr_(1- x )WO_4 was prepared by solid state reaction and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belongs to tetragonal system, which is consistent with space group I4_1/a. Lattice parameters in the systems Ca_ x Sr_(1- x )WO_4 were found to vary linearly with compositions. The emission and excitation spectra were measured. The miscibility, luminescence properties of Tb^(3+)-doped Ca_ x Sr_(1- x )WO_4 and energy transfer mechanism were discussed.展开更多
The energy transfer phenomenon of Ce→Gd→Tb via Gd sublattice and its depandence has been investigated in GdxY-1-xP5O14:Ce,Tb.The fluorescent and excitation spectra of Gdp5O14,Gdp5O14:Ce,Gdp5O14:Tb and GdxY-1xP5O14:C...The energy transfer phenomenon of Ce→Gd→Tb via Gd sublattice and its depandence has been investigated in GdxY-1-xP5O14:Ce,Tb.The fluorescent and excitation spectra of Gdp5O14,Gdp5O14:Ce,Gdp5O14:Tb and GdxY-1xP5O14:Ce,Tb and absorption spectrum of Gdp5O14 have been studied.The results show that as x is larger than 0.7.the energy transfer from Ce3+ via Gd3+to Tb3+ is obvious.The main reason for the energy transfer of Ce→Gd→Tb being efficient in the region x>0.7 is that the spectral overlap between Ce3+ emission spectrum and Gd3+ absorption spectrum increases and the structure changes from monoclinic Ⅱ(C2/c) layer structure(x<0.7) to monoclinic I(P21/c) ribbon structure.展开更多
Preparation, structure and spectral properties of rare earth pentaphosphates Gd_xY_(1-x)P_5O_(14): Ce, Tb have been investigated. When x>0. 7, the pentaphosphates belong to monoclinic crystal system Ⅰ with space g...Preparation, structure and spectral properties of rare earth pentaphosphates Gd_xY_(1-x)P_5O_(14): Ce, Tb have been investigated. When x>0. 7, the pentaphosphates belong to monoclinic crystal system Ⅰ with space group P2_1/c (C). When x≤0. 7. they belong to monoclinic crystal system Ⅱ with C2/c (C). The fluorescent and excitation spectra of Gdp_5O_(14), GdP_5O_(14): Ce. GdP_5O_(14) : Tb and Gd_xY_(1-x)P_5O_(14) : Ce, Tb have been studied and the energy transfer phenomenon from Ce(3+)→Gd(3+)→Tb(3+) by the medium of Gd(3+) sublattice has been determined.展开更多
文摘Tb^(3+)-doped Ca_ x Sr_(1- x )WO_4 was prepared by solid state reaction and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belongs to tetragonal system, which is consistent with space group I4_1/a. Lattice parameters in the systems Ca_ x Sr_(1- x )WO_4 were found to vary linearly with compositions. The emission and excitation spectra were measured. The miscibility, luminescence properties of Tb^(3+)-doped Ca_ x Sr_(1- x )WO_4 and energy transfer mechanism were discussed.
文摘The energy transfer phenomenon of Ce→Gd→Tb via Gd sublattice and its depandence has been investigated in GdxY-1-xP5O14:Ce,Tb.The fluorescent and excitation spectra of Gdp5O14,Gdp5O14:Ce,Gdp5O14:Tb and GdxY-1xP5O14:Ce,Tb and absorption spectrum of Gdp5O14 have been studied.The results show that as x is larger than 0.7.the energy transfer from Ce3+ via Gd3+to Tb3+ is obvious.The main reason for the energy transfer of Ce→Gd→Tb being efficient in the region x>0.7 is that the spectral overlap between Ce3+ emission spectrum and Gd3+ absorption spectrum increases and the structure changes from monoclinic Ⅱ(C2/c) layer structure(x<0.7) to monoclinic I(P21/c) ribbon structure.
文摘Preparation, structure and spectral properties of rare earth pentaphosphates Gd_xY_(1-x)P_5O_(14): Ce, Tb have been investigated. When x>0. 7, the pentaphosphates belong to monoclinic crystal system Ⅰ with space group P2_1/c (C). When x≤0. 7. they belong to monoclinic crystal system Ⅱ with C2/c (C). The fluorescent and excitation spectra of Gdp_5O_(14), GdP_5O_(14): Ce. GdP_5O_(14) : Tb and Gd_xY_(1-x)P_5O_(14) : Ce, Tb have been studied and the energy transfer phenomenon from Ce(3+)→Gd(3+)→Tb(3+) by the medium of Gd(3+) sublattice has been determined.
