Eu3+ activated CaWO4 was prepared by high temperature solid state reaction technique. Red afterglow was observed for in the CaWO4∶Eu after exciting with 254 nm light due to Eu3+ transition from 5D0 to 7FJ (J=0, 1, 2,...Eu3+ activated CaWO4 was prepared by high temperature solid state reaction technique. Red afterglow was observed for in the CaWO4∶Eu after exciting with 254 nm light due to Eu3+ transition from 5D0 to 7FJ (J=0, 1, 2, 3,4). By the cal culation of the thermoluminescence spectrum of CaWO4∶Eu, we conclude that there were two types of trap centers: VCa″ was formed by substitution of Ca2+ by Eu3 + and complex traps were produced because of substitution of W6+ by Eu3+.展开更多
A novel chelate Eu(TTA) 2(PMTBBP)Phen, which contained ligand 1 pheny 3 methyl 4 (4 t butylbenzoyl) 5 pyrazolone(HPMTBBP), 4,4,4 trifluro 1 (2 thienyl) 1,3 butandione(HTTA) and phenanthroline(Phen), was synthesized....A novel chelate Eu(TTA) 2(PMTBBP)Phen, which contained ligand 1 pheny 3 methyl 4 (4 t butylbenzoyl) 5 pyrazolone(HPMTBBP), 4,4,4 trifluro 1 (2 thienyl) 1,3 butandione(HTTA) and phenanthroline(Phen), was synthesized. Its chemical structure was elucidated by IR, UV, 1H NMR, MS, DSC and elementary analysis. The influence of acylpyrazolone on fluorescent intensity of the new chelate was studied. The results showed that Eu(TTA) 2(PMTBBP)Phen had more excellent PL properties and better film formation than that of Eu(TTA) 3Phen. [WT5HZ]展开更多
The new Eu 3+ doped lanthanum oxysulfide phosphors,which have the orange-red long afterg low emission,were synthesized by solid-state reaction method.The synthesized phosphors were characterized by X-ray diffraction.T...The new Eu 3+ doped lanthanum oxysulfide phosphors,which have the orange-red long afterg low emission,were synthesized by solid-state reaction method.The synthesized phosphors were characterized by X-ray diffraction.The excitation and emission spectra,afterglow spectra and afterglow decay curves were examined.XRD confirm ed the phosphor as pure phase La 2 O 2 S.The phosphors showed typical transitions 5 D J (J=0,1) → 7 F J (J=0,1,2,3,4)of Eu 3+ .The photoluminescence spectra and afterglow spectra presented the regular alteration with various Eu 3+ concentration,due to cross relaxation between energy levels of Eu 3+ .In addition,we studied the effects of activator concentration and dopants species on the afterglow property.The data showed afterglow result was the bes t with2%Eu 3+ and doped with Mg 2+ and Zr 4+ .A prominent phosphorescence can be seen in this phosphor after illuminated with UV light.展开更多
文摘Eu3+ activated CaWO4 was prepared by high temperature solid state reaction technique. Red afterglow was observed for in the CaWO4∶Eu after exciting with 254 nm light due to Eu3+ transition from 5D0 to 7FJ (J=0, 1, 2, 3,4). By the cal culation of the thermoluminescence spectrum of CaWO4∶Eu, we conclude that there were two types of trap centers: VCa″ was formed by substitution of Ca2+ by Eu3 + and complex traps were produced because of substitution of W6+ by Eu3+.
文摘A novel chelate Eu(TTA) 2(PMTBBP)Phen, which contained ligand 1 pheny 3 methyl 4 (4 t butylbenzoyl) 5 pyrazolone(HPMTBBP), 4,4,4 trifluro 1 (2 thienyl) 1,3 butandione(HTTA) and phenanthroline(Phen), was synthesized. Its chemical structure was elucidated by IR, UV, 1H NMR, MS, DSC and elementary analysis. The influence of acylpyrazolone on fluorescent intensity of the new chelate was studied. The results showed that Eu(TTA) 2(PMTBBP)Phen had more excellent PL properties and better film formation than that of Eu(TTA) 3Phen. [WT5HZ]
文摘The new Eu 3+ doped lanthanum oxysulfide phosphors,which have the orange-red long afterg low emission,were synthesized by solid-state reaction method.The synthesized phosphors were characterized by X-ray diffraction.The excitation and emission spectra,afterglow spectra and afterglow decay curves were examined.XRD confirm ed the phosphor as pure phase La 2 O 2 S.The phosphors showed typical transitions 5 D J (J=0,1) → 7 F J (J=0,1,2,3,4)of Eu 3+ .The photoluminescence spectra and afterglow spectra presented the regular alteration with various Eu 3+ concentration,due to cross relaxation between energy levels of Eu 3+ .In addition,we studied the effects of activator concentration and dopants species on the afterglow property.The data showed afterglow result was the bes t with2%Eu 3+ and doped with Mg 2+ and Zr 4+ .A prominent phosphorescence can be seen in this phosphor after illuminated with UV light.
