A green long persistent luminescence（LPL） phosphor Ca3Ga4O9：Tb3＋/Zn2＋ was prepared. Ca3 Ga4 O9 matrix exhibits blue self-activated LPL due to the creation of intrinsic traps. When Tb3＋ is doped, the photolumines...A green long persistent luminescence（LPL） phosphor Ca3Ga4O9：Tb3＋/Zn2＋ was prepared. Ca3 Ga4 O9 matrix exhibits blue self-activated LPL due to the creation of intrinsic traps. When Tb3＋ is doped, the photoluminescence（PL） and LPL colors change from blue to green with their intensities significantly enhanced. The doping of Zn^（2＋） evidently improves the PL and LPL performances of the Ca3Ga4O9 matrix and Ca3Ga4O9：Tb^（3＋）. The thermoluminescence（TL） spectra show that a successive trap distribution is formed by multiple intrinsic traps with different depths in the Ca3 Ga4 O9 matrix, and the incorporation of Tb^（3＋） and Zn^（2＋） effectively increases the densities of these intrinsic traps. The existence of a successive trap distribution makes the Ca3 Ga4 O9：Tb^（3＋）/Zn^（2＋） phosphor exhibit thermally stable PL and LPL, It is indicated that this phosphor shows great promise for the application such as high-temperature LPL phosphor.展开更多
Ternary complexes of europium and terbium with benzoic acid and 1, 10 phenanthroline [RE(BA) 3phen] (BA=benzoate phen=1,10 phenanthroline) were introduced into a silica matrix by sol gel method. The thermal stabil...Ternary complexes of europium and terbium with benzoic acid and 1, 10 phenanthroline [RE(BA) 3phen] (BA=benzoate phen=1,10 phenanthroline) were introduced into a silica matrix by sol gel method. The thermal stability and luminescence behavior of the complexes in silica gels were studied in comparison with the corresponding solid state complexes by thermal decomposition, excitation and emission spectra. The thermal stability of the complexes is enhanced in silica gel matrix and the luminescence remaines unchanged.展开更多
A series of Tb^3＋ mono-doped and Ce^3＋-Tb^3＋ co-doped Sr3Gd2（Si3O9）2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2（Si3O9...A series of Tb^3＋ mono-doped and Ce^3＋-Tb^3＋ co-doped Sr3Gd2（Si3O9）2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2（Si3O9）2：Tb^3＋ samples showed broad excitation spectrum from 250 to 400 nm and presented characteristic emission transitions ^5D4→^7FJ（J=6, 5, 4, 3） of Tb^3＋ under 313 nm excitation, which were located at about 488, 541, 584 and 620 nm. The emission intensities of Tb^3＋ rose steadily in Sr3Gd2（Si3O9）2 host with the increase of Tb^3＋ concentration even though Gd^3＋ ions were completely replaced by Tb^3＋ ions. The Ce^3＋ ion as a sensitizer could efficiently improve the performance of Tb^3＋ ion. First, with Ce^3＋ co-doping, the excitation spectrum of Tb^3＋ monitored at 541 nm showed a similar band that responds to the violet emission of Ce^3＋ monitored at 416 nm. Second, the quantum yields of Sr3Gd2（Si3O9）2：Tb^3＋ phosphors could be enhanced from 26.6% to 80.2% by co-doping Ce^3＋. Finally, the co-doping of Ce^3＋ was also effective to improve the thermal stability of Sr3Gd2（Si3O9）2：Tb^3＋. As the temperature rose to 150 oC, the emission intensity of Tb^3＋ remained at about 83.6% of that measured at room temperature, which was better than the commercial YAG：Ce phosphor in terms of their thermal quenching properties. These results indicated that the as-prepared Sr3Gd2（Si3O9）2：Tb^3＋,Ce^3＋ samples could be used as green emission phosphors for possible applications in near ultraviolet based WLEDs.展开更多
A novel mixed-ligand coordination polymer [Zn(BTA)(ip)0.5]n(1, HBTA = benzotriazole, H2 ip = isophthalic acid) has been synthesized under hydrothermal conditions, which was further characterized by X-ray diffraction, ...A novel mixed-ligand coordination polymer [Zn(BTA)(ip)0.5]n(1, HBTA = benzotriazole, H2 ip = isophthalic acid) has been synthesized under hydrothermal conditions, which was further characterized by X-ray diffraction, IR spectrum, elemental analysis and TG-DTA experiments. Complex 1 crystallizes in monoclinic system, space group Pnma with a = 8.9731(5), b = 22.0477(12), c = 10.0217(5) ?, V = 1982.66(18) ?3, Z = 8, C10 H6 ZnN3 O2, Mr = 265.55, Dc = 1.779 g/cm3, μ = 2.462 mm-1, F(000) = 1064, the final R = 0.0225 and wR = 0.0652 with I > 2σ(I). This complex is a 3 D framework with the(42,62,82)(4,62,83) topology. Furthermore, the thermal stability of complex 1 is observed to be dependent on the polymeric structure nature. Strong solid-state luminescence emissions suggest that complex 1 is a good candidate for light emission materials.展开更多
A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were invest...A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were investigated. According to the phase composition analyzed by X-ray powder diffraction, there is no crystalline phase except Ba2Ca(BO3)2 in the sample. Ba2Ca(BO3)2:Dy3+ can produce white emission under 348 nm excitation. The emission intensities of Ba2Ca(BO3)2:Dy3+ are affected by Dy3+ concentration. The concentration quenching effect was analyzed, and the concentration quenching mechanism was verified as dipole-dipole interaction. The critical distance(R c) obtained based on the crystal structure data is 2.911 nm. At 150℃, the emission intensity of Ba2Ca(BO3)2:Dy3+ is 68.0% of the initial value at room temperature. The activation energy for the thermal quenching calculated is 0.202 e V. Moreover, the CIE chromaticity coordinates of Ba2Ca(BO3)2:Dy3+ locate in the white region of(0.319, 0.356).展开更多
A new Sr（Ⅱ） complex, [Sr（Hsip）（H2O）] （1, NaH2sip = 5-sulfoisophthalic acid monosodium）, has been synthesized by solvothermal reaction of SrCO3 and NaH2sip at 120 ℃, and characterized by single-crystal X-ray ...A new Sr（Ⅱ） complex, [Sr（Hsip）（H2O）] （1, NaH2sip = 5-sulfoisophthalic acid monosodium）, has been synthesized by solvothermal reaction of SrCO3 and NaH2sip at 120 ℃, and characterized by single-crystal X-ray diffraction studies, elemental analysis and FT-IR. Single- crystal X-ray diffraction reveals that compound 1 has a 3D architecture, and there is only one crystallographically independent Sr（Ⅱ） ion in 1. The coordination geometry of Sr（Ⅱ） is a distorted tetragonai anti-prism. The whole Hsip2- ligand performs aμ6-coordination model. In the solid state, complex 1 shows luminescence with the maximum emission intensity at 417 nm upon excitation at 320 nm. Thermal stability of complex 1 was also investigated.展开更多
基金The National Natural Science Foundation of China(No.50902042)the Natural Science Foundation of Hebei Province,China(Nos.A2014201035,E2014201037)the Education Office Research Foundation of Hebei Province,China(Nos.ZD2014036,QN2014085)
基金supported by the National Natural Science Foundation of China(11774138)the Society Development Foundation of Yunnan Province(2016FA021)the Kunming University of Science and Technology(KKSY201632046)
文摘A green long persistent luminescence（LPL） phosphor Ca3Ga4O9：Tb3＋/Zn2＋ was prepared. Ca3 Ga4 O9 matrix exhibits blue self-activated LPL due to the creation of intrinsic traps. When Tb3＋ is doped, the photoluminescence（PL） and LPL colors change from blue to green with their intensities significantly enhanced. The doping of Zn^（2＋） evidently improves the PL and LPL performances of the Ca3Ga4O9 matrix and Ca3Ga4O9：Tb^（3＋）. The thermoluminescence（TL） spectra show that a successive trap distribution is formed by multiple intrinsic traps with different depths in the Ca3 Ga4 O9 matrix, and the incorporation of Tb^（3＋） and Zn^（2＋） effectively increases the densities of these intrinsic traps. The existence of a successive trap distribution makes the Ca3 Ga4 O9：Tb^（3＋）/Zn^（2＋） phosphor exhibit thermally stable PL and LPL, It is indicated that this phosphor shows great promise for the application such as high-temperature LPL phosphor.
文摘Ternary complexes of europium and terbium with benzoic acid and 1, 10 phenanthroline [RE(BA) 3phen] (BA=benzoate phen=1,10 phenanthroline) were introduced into a silica matrix by sol gel method. The thermal stability and luminescence behavior of the complexes in silica gels were studied in comparison with the corresponding solid state complexes by thermal decomposition, excitation and emission spectra. The thermal stability of the complexes is enhanced in silica gel matrix and the luminescence remaines unchanged.
基金Project supported by National Natural Science Foundation of China(21571162)the Guangdong Province Enterprise-University-Academy Collaborative Project(2012B091100474)
文摘A series of Tb^3＋ mono-doped and Ce^3＋-Tb^3＋ co-doped Sr3Gd2（Si3O9）2 phosphors with high thermal stability and quantum yields were successfully prepared via the solid state reaction. The as-prepared Sr3Gd2（Si3O9）2：Tb^3＋ samples showed broad excitation spectrum from 250 to 400 nm and presented characteristic emission transitions ^5D4→^7FJ（J=6, 5, 4, 3） of Tb^3＋ under 313 nm excitation, which were located at about 488, 541, 584 and 620 nm. The emission intensities of Tb^3＋ rose steadily in Sr3Gd2（Si3O9）2 host with the increase of Tb^3＋ concentration even though Gd^3＋ ions were completely replaced by Tb^3＋ ions. The Ce^3＋ ion as a sensitizer could efficiently improve the performance of Tb^3＋ ion. First, with Ce^3＋ co-doping, the excitation spectrum of Tb^3＋ monitored at 541 nm showed a similar band that responds to the violet emission of Ce^3＋ monitored at 416 nm. Second, the quantum yields of Sr3Gd2（Si3O9）2：Tb^3＋ phosphors could be enhanced from 26.6% to 80.2% by co-doping Ce^3＋. Finally, the co-doping of Ce^3＋ was also effective to improve the thermal stability of Sr3Gd2（Si3O9）2：Tb^3＋. As the temperature rose to 150 oC, the emission intensity of Tb^3＋ remained at about 83.6% of that measured at room temperature, which was better than the commercial YAG：Ce phosphor in terms of their thermal quenching properties. These results indicated that the as-prepared Sr3Gd2（Si3O9）2：Tb^3＋,Ce^3＋ samples could be used as green emission phosphors for possible applications in near ultraviolet based WLEDs.
基金supported by the Tianjin Training Programs of Innovation and Entrepreneurship for Undergraduates(No.201810065047)
文摘A novel mixed-ligand coordination polymer [Zn(BTA)(ip)0.5]n(1, HBTA = benzotriazole, H2 ip = isophthalic acid) has been synthesized under hydrothermal conditions, which was further characterized by X-ray diffraction, IR spectrum, elemental analysis and TG-DTA experiments. Complex 1 crystallizes in monoclinic system, space group Pnma with a = 8.9731(5), b = 22.0477(12), c = 10.0217(5) ?, V = 1982.66(18) ?3, Z = 8, C10 H6 ZnN3 O2, Mr = 265.55, Dc = 1.779 g/cm3, μ = 2.462 mm-1, F(000) = 1064, the final R = 0.0225 and wR = 0.0652 with I > 2σ(I). This complex is a 3 D framework with the(42,62,82)(4,62,83) topology. Furthermore, the thermal stability of complex 1 is observed to be dependent on the polymeric structure nature. Strong solid-state luminescence emissions suggest that complex 1 is a good candidate for light emission materials.
文摘A white emitting phosphor Ba2Ca(BO3)2:Dy3+ was synthesized via a high temperature solid state reaction at 1000℃ for 5 h. The luminescence, mole fraction quenching and thermal stability of Ba2Ca(BO3)2:Dy3+ were investigated. According to the phase composition analyzed by X-ray powder diffraction, there is no crystalline phase except Ba2Ca(BO3)2 in the sample. Ba2Ca(BO3)2:Dy3+ can produce white emission under 348 nm excitation. The emission intensities of Ba2Ca(BO3)2:Dy3+ are affected by Dy3+ concentration. The concentration quenching effect was analyzed, and the concentration quenching mechanism was verified as dipole-dipole interaction. The critical distance(R c) obtained based on the crystal structure data is 2.911 nm. At 150℃, the emission intensity of Ba2Ca(BO3)2:Dy3+ is 68.0% of the initial value at room temperature. The activation energy for the thermal quenching calculated is 0.202 e V. Moreover, the CIE chromaticity coordinates of Ba2Ca(BO3)2:Dy3+ locate in the white region of(0.319, 0.356).
基金supported by the National Natural Science Foundation of China(41472047)Science Research Starting Project of Chuzhou University(2014qd035)Student Creative Project of Chuzhou University
文摘A new Sr（Ⅱ） complex, [Sr（Hsip）（H2O）] （1, NaH2sip = 5-sulfoisophthalic acid monosodium）, has been synthesized by solvothermal reaction of SrCO3 and NaH2sip at 120 ℃, and characterized by single-crystal X-ray diffraction studies, elemental analysis and FT-IR. Single- crystal X-ray diffraction reveals that compound 1 has a 3D architecture, and there is only one crystallographically independent Sr（Ⅱ） ion in 1. The coordination geometry of Sr（Ⅱ） is a distorted tetragonai anti-prism. The whole Hsip2- ligand performs aμ6-coordination model. In the solid state, complex 1 shows luminescence with the maximum emission intensity at 417 nm upon excitation at 320 nm. Thermal stability of complex 1 was also investigated.
