A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimen...A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimental results indicate broadband cyan emission of Bi^(3+)and characteristic orange-red emission of Sm^(3+)can be effectively tuned by changing the ratios of PO^(3−)_(4)/VO^(3−)_(4) in Gd(P_(x)V_(1−x))O_(4):1 at%Sm^(3+),1 at%Bi^(3+),and the energy transfer process among VO^(3−)_(4),Sm^(3+),Bi^(3+) also can be adjusted.Based on this,warm white light emitting can be realized by further optimizing the doping concentration of Sm^(3+) in the phosphors.At 423 K,the PL intensity of Gd(P_(0.7)V_(0.3))O_(4):2 at%Sm^(3+),1 at%Bi^(3+) remains~84.3%of the initial value at 293 K,while the measured quantum efficiency is 67.8%.EL spectrum analysis results of the fabricated white light emitting diode(wLED)based on a 310 nm UV-chip and Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)phosphors imply low correlated color temperature(3132 K)and appropriate color-rending index(R_(a)=82.7).These results demonstrate that Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)is a good candidate for manufacturing UV-activated warm white light emitting diodes.展开更多
Fluorescence enhancement of red and blue concurrently emitting Ba3MgSi2O8:Eu2+,Mn2+ phosphors for plant cultivation has been investigated by Dy3+ addition.The Ba3MgSi2O8:Eu2+,Mn2+,Dy3+(BMS-EMD) phosphors have two-colo...Fluorescence enhancement of red and blue concurrently emitting Ba3MgSi2O8:Eu2+,Mn2+ phosphors for plant cultivation has been investigated by Dy3+ addition.The Ba3MgSi2O8:Eu2+,Mn2+,Dy3+(BMS-EMD) phosphors have two-color emissions at the wavelength peak values of 437 nm and 620 nm at the excitation of 350 nm.The two emission bands are coincident with the absorption spectrum for photosynthesis of plants.An obvious enhancement effect has been observed upon addition of Dy3+ with amount of 0.03 mol%,in which the ...展开更多
A two colour phosphor Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ was synthesized using solid-state reaction method. Luminescence of Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ showed 416 and 618 nm emission bands attributed to Ce^3＋ ...A two colour phosphor Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ was synthesized using solid-state reaction method. Luminescence of Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ showed 416 and 618 nm emission bands attributed to Ce^3＋ and Eu^2＋ emission, respectively. Energy transfer occurred from Ce^3＋ to Eu^2＋ through a significant overlap of Eu^2＋ excitation spectrum with Ce^3＋ emission spectum in Ba2Mg（BO3）2. They also showed that under the excitation of UV radiation, bluish or yellowish white light was generated by coupling a broad blue emission band and a red emission band. By combining with green phosphor, Ba2Mg（BO3）：Ce^3＋,Eu^2＋,Na^＋ phosphor showed potential application for white light-emitting diodes （LEDs）.展开更多
A series of tunable phosphors NaAlSiO_4：Ce^（3＋）,Sm^（3＋） were synthesized using a conventional high-temperature, solid-state method. Crystal structure, photoluminescence excitation, and emission spectra with flu...A series of tunable phosphors NaAlSiO_4：Ce^（3＋）,Sm^（3＋） were synthesized using a conventional high-temperature, solid-state method. Crystal structure, photoluminescence excitation, and emission spectra with fluorescence decay curves were investigated. Under UV excitation（325 nm）, NaAlSiO_4：Ce^（3＋）,Sm^（3＋） showed strong blue emission located at 444 nm and orange-reddish emission centered at 563, 601, 648 and 712 nm, stemming from the characteristic emission for 4f-5d transition of Ce^（3＋） and ~4G_（5/2）→~6H_J（J=5/2, 7/2, 9/2, 11/2） transition of Sm^（3＋）, respectively. In addition, we studied the detailed energy transfer process between Ce^（3＋） and Sm^（3＋） and found that it belonged to dipole-dipole resonance energy transfer. Furthermore, we noted that the white light emitting from the Ce^（3＋）, Sm^（3＋） co-doped phosphors with the color coordinate（x=0.313, y=0.283） could be observed under 325 nm excitation, which was close to the ideal white light（x=0.33, y=0.33）. The results indicated that this phosphor has a potential application as a single-phased alumino-silicate phosphor for ultraviolet white light-emitting diodes（UV-WLEDs）.展开更多
The establishment of an approach to design tunable yellow emission through singly doped single-phased phosphors to obtain white LED-based InGaN chip was reported. BaY2–xS4：xHo3＋ phosphors were prepared by the high ...The establishment of an approach to design tunable yellow emission through singly doped single-phased phosphors to obtain white LED-based InGaN chip was reported. BaY2–xS4：xHo3＋ phosphors were prepared by the high temperature solid state reaction and characterized by X-ray diffraction and photoluminescence spectra. Under the excitation of 465 nm,the emission spectra of these phosphors exhibited three sharp emission lines peaked at about 492,543 and 661 nm of Ho3＋ corresponding to 5F3,5F4 （5S2） and 5F5→5I8 transitions,respectively,with comparable intensities,resulting in a yellow light emission. The luminescence mechanism for Ho3＋ in BaY2S4 was explained.展开更多
In order to obtain a single-host white-light phosphor, a series of KCaPO4 powder samples tri-doped with Eu2＋, Tb3＋ and Mn2＋ were synthesized via high-temperature solid-state reaction method. Their structural and lu...In order to obtain a single-host white-light phosphor, a series of KCaPO4 powder samples tri-doped with Eu2＋, Tb3＋ and Mn2＋ were synthesized via high-temperature solid-state reaction method. Their structural and luminescence properties were investigated. Under proper ultraviolet excitation （255-405 urn）, white light was obtained, consisting of blue, green and red emissions stemming from Eu2＋, Th3＋, Mn2＋ ions respectively. The temperature stability of our sample was analyzed by studying the variation tendeney of CIE chromaticity coordinates at different temperatures. The results indicated that this phosphor could yield good color stability when utilized in WLED.展开更多
基金Project supported by the National Natural Science Foundation of China(51972181,61705231)Major Basic Research Projects of Shandong Natural Science Foundation(ZR2018ZB0650)+2 种基金China Postdoctoral Science Foundation(2015M580573)High Quality Course Construction Project of Graduate Education in Shandong Province(SDYKC18051)Postgraduate Tutor Ability Improvement Project of Shandong Province(SDYY17179)。
文摘A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimental results indicate broadband cyan emission of Bi^(3+)and characteristic orange-red emission of Sm^(3+)can be effectively tuned by changing the ratios of PO^(3−)_(4)/VO^(3−)_(4) in Gd(P_(x)V_(1−x))O_(4):1 at%Sm^(3+),1 at%Bi^(3+),and the energy transfer process among VO^(3−)_(4),Sm^(3+),Bi^(3+) also can be adjusted.Based on this,warm white light emitting can be realized by further optimizing the doping concentration of Sm^(3+) in the phosphors.At 423 K,the PL intensity of Gd(P_(0.7)V_(0.3))O_(4):2 at%Sm^(3+),1 at%Bi^(3+) remains~84.3%of the initial value at 293 K,while the measured quantum efficiency is 67.8%.EL spectrum analysis results of the fabricated white light emitting diode(wLED)based on a 310 nm UV-chip and Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)phosphors imply low correlated color temperature(3132 K)and appropriate color-rending index(R_(a)=82.7).These results demonstrate that Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)is a good candidate for manufacturing UV-activated warm white light emitting diodes.
基金supported by National Natural Science Foundation of China (Grant No 50872091)the Natural Science Foundation of Tianjin,China(06YFJMJC02300,06TXTJJC14602)
文摘Fluorescence enhancement of red and blue concurrently emitting Ba3MgSi2O8:Eu2+,Mn2+ phosphors for plant cultivation has been investigated by Dy3+ addition.The Ba3MgSi2O8:Eu2+,Mn2+,Dy3+(BMS-EMD) phosphors have two-color emissions at the wavelength peak values of 437 nm and 620 nm at the excitation of 350 nm.The two emission bands are coincident with the absorption spectrum for photosynthesis of plants.An obvious enhancement effect has been observed upon addition of Dy3+ with amount of 0.03 mol%,in which the ...
基金supported by National Natural Science Foundation of China (10804099,11274299)the Natural Science Foundation of Zhejiang Province(Y4110536)the Key Science and Technology Innovation Team of Zhejiang Province (2009R50002)
文摘A two colour phosphor Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ was synthesized using solid-state reaction method. Luminescence of Ba2Mg（BO3）2：Ce^3＋,Eu^2＋,Na^＋ showed 416 and 618 nm emission bands attributed to Ce^3＋ and Eu^2＋ emission, respectively. Energy transfer occurred from Ce^3＋ to Eu^2＋ through a significant overlap of Eu^2＋ excitation spectrum with Ce^3＋ emission spectum in Ba2Mg（BO3）2. They also showed that under the excitation of UV radiation, bluish or yellowish white light was generated by coupling a broad blue emission band and a red emission band. By combining with green phosphor, Ba2Mg（BO3）：Ce^3＋,Eu^2＋,Na^＋ phosphor showed potential application for white light-emitting diodes （LEDs）.
基金supported by the National Natural Science Foundation of China(11464045)Autonomous Region Postgraduate Research Innovation Fund Project(XJGRI2016093)+1 种基金the subject of Xinjiang Normal University Key Laboratory(KWFG1605)the Introduction Program of High-Level Talents of Xinjiang Province
文摘A series of tunable phosphors NaAlSiO_4：Ce^（3＋）,Sm^（3＋） were synthesized using a conventional high-temperature, solid-state method. Crystal structure, photoluminescence excitation, and emission spectra with fluorescence decay curves were investigated. Under UV excitation（325 nm）, NaAlSiO_4：Ce^（3＋）,Sm^（3＋） showed strong blue emission located at 444 nm and orange-reddish emission centered at 563, 601, 648 and 712 nm, stemming from the characteristic emission for 4f-5d transition of Ce^（3＋） and ~4G_（5/2）→~6H_J（J=5/2, 7/2, 9/2, 11/2） transition of Sm^（3＋）, respectively. In addition, we studied the detailed energy transfer process between Ce^（3＋） and Sm^（3＋） and found that it belonged to dipole-dipole resonance energy transfer. Furthermore, we noted that the white light emitting from the Ce^（3＋）, Sm^（3＋） co-doped phosphors with the color coordinate（x=0.313, y=0.283） could be observed under 325 nm excitation, which was close to the ideal white light（x=0.33, y=0.33）. The results indicated that this phosphor has a potential application as a single-phased alumino-silicate phosphor for ultraviolet white light-emitting diodes（UV-WLEDs）.
基金Project supported by the National Natural Science Foundation of China (20971042 and 50772035)the Science and Technology Office of Educa-tion Department of Hunan Province (10A070)the Science and Technology Bureau of Changsha City Government (K0902014-11)
文摘The establishment of an approach to design tunable yellow emission through singly doped single-phased phosphors to obtain white LED-based InGaN chip was reported. BaY2–xS4：xHo3＋ phosphors were prepared by the high temperature solid state reaction and characterized by X-ray diffraction and photoluminescence spectra. Under the excitation of 465 nm,the emission spectra of these phosphors exhibited three sharp emission lines peaked at about 492,543 and 661 nm of Ho3＋ corresponding to 5F3,5F4 （5S2） and 5F5→5I8 transitions,respectively,with comparable intensities,resulting in a yellow light emission. The luminescence mechanism for Ho3＋ in BaY2S4 was explained.
基金Supported by Natural Science Foundation of Liaoning Province(20170540074)Start-up Funding for Doctoral Researchers of Dalian Polytechnic University(61020726)~~
基金supported by National Key Basic Research Program of China(2013CB921800)the National Natural Science Foundation of China(11374291,11204292,11274299,11311120047)+1 种基金the Fundamental Research Funds for the Central Universities(WK2030020021)Anhui Provincial Natural Science Foundation(1308085QE75)
文摘In order to obtain a single-host white-light phosphor, a series of KCaPO4 powder samples tri-doped with Eu2＋, Tb3＋ and Mn2＋ were synthesized via high-temperature solid-state reaction method. Their structural and luminescence properties were investigated. Under proper ultraviolet excitation （255-405 urn）, white light was obtained, consisting of blue, green and red emissions stemming from Eu2＋, Th3＋, Mn2＋ ions respectively. The temperature stability of our sample was analyzed by studying the variation tendeney of CIE chromaticity coordinates at different temperatures. The results indicated that this phosphor could yield good color stability when utilized in WLED.
