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Yangai Liu - One of the best experts on this subject based on the ideXlab platform.
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crystal structure and Luminescence Property of a novel single phase white light emission phosphor kcabi po4 2 dy3
Materials Research Bulletin, 2017Co-Authors: Jian Chen, Zhaohui Huang, Yangai Liu, Lefu Mei, Jiangyan Yuan, Yufei Xia, Minghao FangAbstract:Abstract A novel white light emitting phosphor KCaBi(PO 4 ) 2 :Dy 3+ for UV excitations has been synthesized by the solid state reaction technique. The powder X-ray diffraction patterns, Rietveld refinement and XPS were utilized to confirm the phase composite and crystal structure. The excitation and emission spectra, decay curves and chromaticity coordinates of the as-prepared phosphors were characterized to investigate the photoLuminescence properties for application in white light-emitting diodes. The results revealed that the KCaBi(PO 4 ) 2 :Dy 3+ phosphors can be effectively assimilated with near ultraviolet, and exhibit two emission bands peaked at 480 nm(blue light) and 580 nm(yellow light) originating from the 4 F 9/2- 6 H 15/2 , 4 F 9/2 - 6 H 13/2 transitions of Dy 3+ , respectively. The critical distance was calculated to be about 17.96 A and the concentration quenching mechanism was verified as dipole-dipole interaction. Additional, the optimal chromaticity coordinates were determined to be (0.3118, 0.3309) and a better thermal stability of the phosphors have been illustrated.
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phase transformation in ca3 po4 2 eu2 via the controlled quenching and increased eu2 content identification of new cyan emitting α ca3 po4 2 eu2 phosphor
Journal of the American Ceramic Society, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Mingyue Chen, Yangai LiuAbstract:A case of phosphor is reported where the cooling rate parameter significantly influences the Luminescence Property. By quenching the sample after the high-temperature solid-state reaction at 1250°C, we successfully prepared the Eu2+-doped α form Ca3(PO4)2 (α-TCP:Eu2+) as a new kind of bright cyan-emitting phosphor. The unusual emission color variation (from cyan to blue) depends on the cooling rate after sintering and Eu2+ doping level as it was observed in the TCP-based phosphors. By the Rietveld analysis, it is revealed that the cyan- and blue-emitting phosphors are two different TCP forms crystallizing in the monoclinic (space group P21/a, α-TCP) and the rhombohedral structure (space group R3c, β-TCP), respectively. Upon 365 nm UV light excitation, α-TCP:Eu2+ exhibits an asymmetric broad-band cyan emission peaking at 480 nm, while β-TCP:Eu2+ displays a relatively narrow-band blue emission peaking at 416 nm. The Eu2+-doping in Ca3(PO4)2 shifts the upper temperature limit of the stable structural range of β form from 1125°C to ≥1250°C. Moreover, the crystal structures of α/β-TCP:Eu2+ were compared in the aspects of compactness and cation site sets. The emission thermal stability of α/β-TCP:Eu2+ was comparatively characterized and the difference was related to the specific host structural features.
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discovery of new solid solution phosphors via cation substitution dependent phase transition in m3 po4 2 eu2 m ca sr ba quasi binary sets
Journal of Physical Chemistry C, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Yangai LiuAbstract:The cation substitution-dependent phase transition was used as a strategy to discover new solid solution phosphors and to efficiently tune the Luminescence Property of divalent europium (Eu2+) in the M3(PO4)2:Eu2+ (M = Ca/Sr/Ba) quasi-binary sets. Several new phosphors including the greenish-white SrCa2(PO4)2:Eu2+, the yellow Sr2Ca(PO4)2:Eu2+, and the cyan Ba2Ca(PO4)2:Eu2+ were reported, and the drastic red shift of the emission toward the phase transition point was discussed. Different behavior of Luminescence evolution in response to structural variation was verified among the three M3(PO4)2:Eu2+ joins. Sr3(PO4)2 and Ba3(PO4)2 form a continuous isostructural solid solution set in which Eu2+ exhibits a similar symmetric narrow-band blue emission centered at 416 nm, whereas Sr2+ substituting Ca2+ in Ca3(PO4)2 induces a composition-dependent phase transition and the peaking emission gets red shifted to 527 nm approaching the phase transition point. In the Ca3–xBax(PO4)2:Eu2+ set, the validity of crystalloc...
Zhaohui Huang - One of the best experts on this subject based on the ideXlab platform.
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crystal structure and Luminescence Property of a novel single phase white light emission phosphor kcabi po4 2 dy3
Materials Research Bulletin, 2017Co-Authors: Jian Chen, Zhaohui Huang, Yangai Liu, Lefu Mei, Jiangyan Yuan, Yufei Xia, Minghao FangAbstract:Abstract A novel white light emitting phosphor KCaBi(PO 4 ) 2 :Dy 3+ for UV excitations has been synthesized by the solid state reaction technique. The powder X-ray diffraction patterns, Rietveld refinement and XPS were utilized to confirm the phase composite and crystal structure. The excitation and emission spectra, decay curves and chromaticity coordinates of the as-prepared phosphors were characterized to investigate the photoLuminescence properties for application in white light-emitting diodes. The results revealed that the KCaBi(PO 4 ) 2 :Dy 3+ phosphors can be effectively assimilated with near ultraviolet, and exhibit two emission bands peaked at 480 nm(blue light) and 580 nm(yellow light) originating from the 4 F 9/2- 6 H 15/2 , 4 F 9/2 - 6 H 13/2 transitions of Dy 3+ , respectively. The critical distance was calculated to be about 17.96 A and the concentration quenching mechanism was verified as dipole-dipole interaction. Additional, the optimal chromaticity coordinates were determined to be (0.3118, 0.3309) and a better thermal stability of the phosphors have been illustrated.
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phase transformation in ca3 po4 2 eu2 via the controlled quenching and increased eu2 content identification of new cyan emitting α ca3 po4 2 eu2 phosphor
Journal of the American Ceramic Society, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Mingyue Chen, Yangai LiuAbstract:A case of phosphor is reported where the cooling rate parameter significantly influences the Luminescence Property. By quenching the sample after the high-temperature solid-state reaction at 1250°C, we successfully prepared the Eu2+-doped α form Ca3(PO4)2 (α-TCP:Eu2+) as a new kind of bright cyan-emitting phosphor. The unusual emission color variation (from cyan to blue) depends on the cooling rate after sintering and Eu2+ doping level as it was observed in the TCP-based phosphors. By the Rietveld analysis, it is revealed that the cyan- and blue-emitting phosphors are two different TCP forms crystallizing in the monoclinic (space group P21/a, α-TCP) and the rhombohedral structure (space group R3c, β-TCP), respectively. Upon 365 nm UV light excitation, α-TCP:Eu2+ exhibits an asymmetric broad-band cyan emission peaking at 480 nm, while β-TCP:Eu2+ displays a relatively narrow-band blue emission peaking at 416 nm. The Eu2+-doping in Ca3(PO4)2 shifts the upper temperature limit of the stable structural range of β form from 1125°C to ≥1250°C. Moreover, the crystal structures of α/β-TCP:Eu2+ were compared in the aspects of compactness and cation site sets. The emission thermal stability of α/β-TCP:Eu2+ was comparatively characterized and the difference was related to the specific host structural features.
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discovery of new solid solution phosphors via cation substitution dependent phase transition in m3 po4 2 eu2 m ca sr ba quasi binary sets
Journal of Physical Chemistry C, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Yangai LiuAbstract:The cation substitution-dependent phase transition was used as a strategy to discover new solid solution phosphors and to efficiently tune the Luminescence Property of divalent europium (Eu2+) in the M3(PO4)2:Eu2+ (M = Ca/Sr/Ba) quasi-binary sets. Several new phosphors including the greenish-white SrCa2(PO4)2:Eu2+, the yellow Sr2Ca(PO4)2:Eu2+, and the cyan Ba2Ca(PO4)2:Eu2+ were reported, and the drastic red shift of the emission toward the phase transition point was discussed. Different behavior of Luminescence evolution in response to structural variation was verified among the three M3(PO4)2:Eu2+ joins. Sr3(PO4)2 and Ba3(PO4)2 form a continuous isostructural solid solution set in which Eu2+ exhibits a similar symmetric narrow-band blue emission centered at 416 nm, whereas Sr2+ substituting Ca2+ in Ca3(PO4)2 induces a composition-dependent phase transition and the peaking emission gets red shifted to 527 nm approaching the phase transition point. In the Ca3–xBax(PO4)2:Eu2+ set, the validity of crystalloc...
Minghao Fang - One of the best experts on this subject based on the ideXlab platform.
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crystal structure and Luminescence Property of a novel single phase white light emission phosphor kcabi po4 2 dy3
Materials Research Bulletin, 2017Co-Authors: Jian Chen, Zhaohui Huang, Yangai Liu, Lefu Mei, Jiangyan Yuan, Yufei Xia, Minghao FangAbstract:Abstract A novel white light emitting phosphor KCaBi(PO 4 ) 2 :Dy 3+ for UV excitations has been synthesized by the solid state reaction technique. The powder X-ray diffraction patterns, Rietveld refinement and XPS were utilized to confirm the phase composite and crystal structure. The excitation and emission spectra, decay curves and chromaticity coordinates of the as-prepared phosphors were characterized to investigate the photoLuminescence properties for application in white light-emitting diodes. The results revealed that the KCaBi(PO 4 ) 2 :Dy 3+ phosphors can be effectively assimilated with near ultraviolet, and exhibit two emission bands peaked at 480 nm(blue light) and 580 nm(yellow light) originating from the 4 F 9/2- 6 H 15/2 , 4 F 9/2 - 6 H 13/2 transitions of Dy 3+ , respectively. The critical distance was calculated to be about 17.96 A and the concentration quenching mechanism was verified as dipole-dipole interaction. Additional, the optimal chromaticity coordinates were determined to be (0.3118, 0.3309) and a better thermal stability of the phosphors have been illustrated.
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phase transformation in ca3 po4 2 eu2 via the controlled quenching and increased eu2 content identification of new cyan emitting α ca3 po4 2 eu2 phosphor
Journal of the American Ceramic Society, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Mingyue Chen, Yangai LiuAbstract:A case of phosphor is reported where the cooling rate parameter significantly influences the Luminescence Property. By quenching the sample after the high-temperature solid-state reaction at 1250°C, we successfully prepared the Eu2+-doped α form Ca3(PO4)2 (α-TCP:Eu2+) as a new kind of bright cyan-emitting phosphor. The unusual emission color variation (from cyan to blue) depends on the cooling rate after sintering and Eu2+ doping level as it was observed in the TCP-based phosphors. By the Rietveld analysis, it is revealed that the cyan- and blue-emitting phosphors are two different TCP forms crystallizing in the monoclinic (space group P21/a, α-TCP) and the rhombohedral structure (space group R3c, β-TCP), respectively. Upon 365 nm UV light excitation, α-TCP:Eu2+ exhibits an asymmetric broad-band cyan emission peaking at 480 nm, while β-TCP:Eu2+ displays a relatively narrow-band blue emission peaking at 416 nm. The Eu2+-doping in Ca3(PO4)2 shifts the upper temperature limit of the stable structural range of β form from 1125°C to ≥1250°C. Moreover, the crystal structures of α/β-TCP:Eu2+ were compared in the aspects of compactness and cation site sets. The emission thermal stability of α/β-TCP:Eu2+ was comparatively characterized and the difference was related to the specific host structural features.
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discovery of new solid solution phosphors via cation substitution dependent phase transition in m3 po4 2 eu2 m ca sr ba quasi binary sets
Journal of Physical Chemistry C, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Yangai LiuAbstract:The cation substitution-dependent phase transition was used as a strategy to discover new solid solution phosphors and to efficiently tune the Luminescence Property of divalent europium (Eu2+) in the M3(PO4)2:Eu2+ (M = Ca/Sr/Ba) quasi-binary sets. Several new phosphors including the greenish-white SrCa2(PO4)2:Eu2+, the yellow Sr2Ca(PO4)2:Eu2+, and the cyan Ba2Ca(PO4)2:Eu2+ were reported, and the drastic red shift of the emission toward the phase transition point was discussed. Different behavior of Luminescence evolution in response to structural variation was verified among the three M3(PO4)2:Eu2+ joins. Sr3(PO4)2 and Ba3(PO4)2 form a continuous isostructural solid solution set in which Eu2+ exhibits a similar symmetric narrow-band blue emission centered at 416 nm, whereas Sr2+ substituting Ca2+ in Ca3(PO4)2 induces a composition-dependent phase transition and the peaking emission gets red shifted to 527 nm approaching the phase transition point. In the Ca3–xBax(PO4)2:Eu2+ set, the validity of crystalloc...
Zhiguo Xia - One of the best experts on this subject based on the ideXlab platform.
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phase transformation in ca3 po4 2 eu2 via the controlled quenching and increased eu2 content identification of new cyan emitting α ca3 po4 2 eu2 phosphor
Journal of the American Ceramic Society, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Mingyue Chen, Yangai LiuAbstract:A case of phosphor is reported where the cooling rate parameter significantly influences the Luminescence Property. By quenching the sample after the high-temperature solid-state reaction at 1250°C, we successfully prepared the Eu2+-doped α form Ca3(PO4)2 (α-TCP:Eu2+) as a new kind of bright cyan-emitting phosphor. The unusual emission color variation (from cyan to blue) depends on the cooling rate after sintering and Eu2+ doping level as it was observed in the TCP-based phosphors. By the Rietveld analysis, it is revealed that the cyan- and blue-emitting phosphors are two different TCP forms crystallizing in the monoclinic (space group P21/a, α-TCP) and the rhombohedral structure (space group R3c, β-TCP), respectively. Upon 365 nm UV light excitation, α-TCP:Eu2+ exhibits an asymmetric broad-band cyan emission peaking at 480 nm, while β-TCP:Eu2+ displays a relatively narrow-band blue emission peaking at 416 nm. The Eu2+-doping in Ca3(PO4)2 shifts the upper temperature limit of the stable structural range of β form from 1125°C to ≥1250°C. Moreover, the crystal structures of α/β-TCP:Eu2+ were compared in the aspects of compactness and cation site sets. The emission thermal stability of α/β-TCP:Eu2+ was comparatively characterized and the difference was related to the specific host structural features.
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discovery of new solid solution phosphors via cation substitution dependent phase transition in m3 po4 2 eu2 m ca sr ba quasi binary sets
Journal of Physical Chemistry C, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Yangai LiuAbstract:The cation substitution-dependent phase transition was used as a strategy to discover new solid solution phosphors and to efficiently tune the Luminescence Property of divalent europium (Eu2+) in the M3(PO4)2:Eu2+ (M = Ca/Sr/Ba) quasi-binary sets. Several new phosphors including the greenish-white SrCa2(PO4)2:Eu2+, the yellow Sr2Ca(PO4)2:Eu2+, and the cyan Ba2Ca(PO4)2:Eu2+ were reported, and the drastic red shift of the emission toward the phase transition point was discussed. Different behavior of Luminescence evolution in response to structural variation was verified among the three M3(PO4)2:Eu2+ joins. Sr3(PO4)2 and Ba3(PO4)2 form a continuous isostructural solid solution set in which Eu2+ exhibits a similar symmetric narrow-band blue emission centered at 416 nm, whereas Sr2+ substituting Ca2+ in Ca3(PO4)2 induces a composition-dependent phase transition and the peaking emission gets red shifted to 527 nm approaching the phase transition point. In the Ca3–xBax(PO4)2:Eu2+ set, the validity of crystalloc...
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structure Luminescence Property and energy transfer behavior of color adjustable la5si2bo13 ce3 mn2 phosphors
RSC Advances, 2014Co-Authors: Haikun Liu, Libing Liao, Zhiguo XiaAbstract:A series of color-adjustable phosphors La5Si2BO13(LSBO):Ce3+,Mn2+ were synthesized through a high temperature solid-state method. The crystal structures of Ce3+ and Mn2+ doped La5Si2BO13 phosphors were refined by the Rietveld method, which were proved to be the apatite-type hexagonal phase (space group of P63/m). It was found that two different La3+ sites in the La5Si2BO13 phase were occupied evenly by Ce3+ and Mn2+ ions, and then the formed vacancy contributed to the charge compensation. La5Si2BO13:Ce3+,Mn2+ phosphors exhibited a broad excitation band ranging from 250 to 375 nm and two broad emission bands centred at 418 nm and 585 nm upon 345 nm excitation. It is found that the emission colors could be tuned from blue-violet (0.1629, 0.0523) to pink (0.3227, 0.1830) by changing the ratio of Ce3+/Mn2+. Moreover, the energy transfer mechanism was verified to be the dipole–dipole interaction, and the critical distance was calculated to be 10.02 A by using the concentration quenching method.
Maxim S. Molokeev - One of the best experts on this subject based on the ideXlab platform.
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Red shift properties, crystal field theory and nephelauxetic effect on Mn4+-doped SrMgAl10-yGayO17 red phosphor for plant growth LED light
Chemical Engineering Journal, 2020Co-Authors: Mao Xia, Cheng Zhou, Zihui Kong, Maxim S. Molokeev, Li Liu, Wai Yeung Wong, Zhi ZhouAbstract:Abstract The discovery of novel Mn4+-doped oxide red phosphor with suitable spectrum for plant growth is a hot issue in the recent years due to the characteristic red photoLuminescence of 2Eg → 4A2 transition in Mn4+ ions. Generally, the emission position of Mn4+ is hard to tune because of specific crystal field in most phosphors. In this work, tunable Luminescence Property with obvious red shift in the spectra is observed in the Mn4+-doped SrMgAl10-yGayO17 red phosphor via simple substitution of Ga3+ for Al3+, and crystal field theory and nephelauxetic effect are employed to explain this phenomenon. Meanwhile, the Ga3+ dopant changes the shape of the spectra because Ga3+ dopant guides the replacement site of Mn4+ and changes the Luminescence center. Improved emission intensity is obtained because appropriate Ga3+ doping leads to larger band gap and reduces non-radiative transitions. Phosphor-converted LED (pc-LED) devices fabricated with blue chip (470 nm) and the as-obtained SrMgAl10-yGayO17:1.0%Mn4+ phosphors emit bright blue and red light, which fit the absorption regions of plant pigments well, thus SrMgAl10-yGayO17:Mn4+ phosphor can be a candidate for plant growth LED light.
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phase transformation in ca3 po4 2 eu2 via the controlled quenching and increased eu2 content identification of new cyan emitting α ca3 po4 2 eu2 phosphor
Journal of the American Ceramic Society, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Mingyue Chen, Yangai LiuAbstract:A case of phosphor is reported where the cooling rate parameter significantly influences the Luminescence Property. By quenching the sample after the high-temperature solid-state reaction at 1250°C, we successfully prepared the Eu2+-doped α form Ca3(PO4)2 (α-TCP:Eu2+) as a new kind of bright cyan-emitting phosphor. The unusual emission color variation (from cyan to blue) depends on the cooling rate after sintering and Eu2+ doping level as it was observed in the TCP-based phosphors. By the Rietveld analysis, it is revealed that the cyan- and blue-emitting phosphors are two different TCP forms crystallizing in the monoclinic (space group P21/a, α-TCP) and the rhombohedral structure (space group R3c, β-TCP), respectively. Upon 365 nm UV light excitation, α-TCP:Eu2+ exhibits an asymmetric broad-band cyan emission peaking at 480 nm, while β-TCP:Eu2+ displays a relatively narrow-band blue emission peaking at 416 nm. The Eu2+-doping in Ca3(PO4)2 shifts the upper temperature limit of the stable structural range of β form from 1125°C to ≥1250°C. Moreover, the crystal structures of α/β-TCP:Eu2+ were compared in the aspects of compactness and cation site sets. The emission thermal stability of α/β-TCP:Eu2+ was comparatively characterized and the difference was related to the specific host structural features.
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discovery of new solid solution phosphors via cation substitution dependent phase transition in m3 po4 2 eu2 m ca sr ba quasi binary sets
Journal of Physical Chemistry C, 2015Co-Authors: Zhaohui Huang, Maxim S. Molokeev, Zhiguo Xia, V V Atuchin, Minghao Fang, Yangai LiuAbstract:The cation substitution-dependent phase transition was used as a strategy to discover new solid solution phosphors and to efficiently tune the Luminescence Property of divalent europium (Eu2+) in the M3(PO4)2:Eu2+ (M = Ca/Sr/Ba) quasi-binary sets. Several new phosphors including the greenish-white SrCa2(PO4)2:Eu2+, the yellow Sr2Ca(PO4)2:Eu2+, and the cyan Ba2Ca(PO4)2:Eu2+ were reported, and the drastic red shift of the emission toward the phase transition point was discussed. Different behavior of Luminescence evolution in response to structural variation was verified among the three M3(PO4)2:Eu2+ joins. Sr3(PO4)2 and Ba3(PO4)2 form a continuous isostructural solid solution set in which Eu2+ exhibits a similar symmetric narrow-band blue emission centered at 416 nm, whereas Sr2+ substituting Ca2+ in Ca3(PO4)2 induces a composition-dependent phase transition and the peaking emission gets red shifted to 527 nm approaching the phase transition point. In the Ca3–xBax(PO4)2:Eu2+ set, the validity of crystalloc...
