Summary of the invention
The present invention aims to provide a kind of bismuth doping phosphoric acid barium yellow fluorescent material, this yellow fluorescent material has UV spectrum district and absorbs, the peak position under ultraviolet excitation with covering 400nm-800nm interval is positioned at 578nm yellow fluorescence, chromaticity coordinates is (0.424,0.460), its fluorescence lifetime is about 20 microseconds.
Another object of the present invention is to provide the preparation method of bismuth doping phosphoric acid barium yellow fluorescent material, and the method adopts cheap bismuth as activator, utilizes traditional high temperature solid state reaction, under normal pressure, prepares.
Realizing the technical scheme that object of the present invention adopts comprises:
A kind of bismuth doping phosphoric acid barium yellow fluorescent material is bismuth doping Ba
3(PO
4)
2crystal, belongs to trigonal system; In bismuth doping phosphoric acid barium yellow fluorescent material, the mol ratio of barium, phosphorus and bismuth element is x (1-y): 2: xy, wherein 3.0≤x≤3.5,0.0001≤y≤0.10.
A preparation method for bismuth doping phosphoric acid barium yellow fluorescent material, comprises the steps:
(1) take the raw materials of compound of baric, phosphorus and bismuth, its mol ratio is pressed barium: phosphorus: bismuth=x (1-y): 2: xy, wherein 3.0≤x≤3.5,0.0001≤y≤0.10; The raw materials of compound of baric is barium carbonate, hydrated barta, barium oxide, nitrate of baryta, barium oxalate or barium acetate; Phosphorous raw materials of compound is primary ammonium phosphate, ammonium hydrogen phosphate, phosphoric acid or Vanadium Pentoxide in FLAKES; The raw materials of compound of bismuth-containing is bismuthous oxide bismuth trioxide, bismuth meal, Bismuth Subcarbonate or bismuth chloride;
(2) by the raw material weighing up, after being ground, carry out pre-burning, controlling calcined temperature is 400~800 ° of C;
(3) product after pre-burning is taken out, after being ground, under high temperature air, fire for the first time, controlling the high temperature air temperature of firing is for the first time 1000~1500 ° of C;
(4) product after firing is for the first time taken out, after being ground, under air or weak reducing atmosphere, fire for the second time, controlling the temperature of firing is for the second time 1000~1500 ° of C; Make bismuth doping phosphoric acid barium yellow fluorescent material.
Further, described step 2 to the temperature rise rate of 400~800 ° of C of calcined temperature is 0.4~4 ° of C/min; .
Described weak reducing atmosphere is carbon monoxide, hydrogen or the nitrogen of Graphite Powder 99 incomplete combustion generation and the mixed gas of hydrogen.
Compared with prior art, the present invention has following advantage and beneficial effect: the feature of fluorescent material prepared by the inventive method is:
(1) have the absorption that covers 220~300nm interval, peak position is positioned at 260nm;
(2) UV-light (220~300nm) excites down the broadband yellow fluorescent with covering 400nm~800nm interval, comprises sodium D
2yellow band;
(3) yellow fluorescence peak position is positioned at 578nm, halfwidth >200nm, and chromaticity coordinates is (0.424,0.460);
(4) under room temperature, fluorescence lifetime is about 20 microseconds.The present invention is expected to obtain application in fields such as illumination, medical treatment, new type light sources.
Embodiment
Below in conjunction with specific embodiment, the present invention is more specifically described in detail, but embodiments of the present invention are not limited to this, for not dated especially processing parameter, can carry out with reference to routine techniques.
Embodiment 1
Choose barium carbonate, primary ammonium phosphate and bismuthous oxide bismuth trioxide are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.15, y=0.01, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 0.83 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 500 ° of C pre-burnings 5 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under high temperature air, fire for the first time, control 1300 ° of C of temperature, fire 5 hours, the sample after firing is taken out, after being ground, under high temperature air, fire for the second time, control 1300 ° of C of temperature, fire 5 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.
Fig. 1 is the powder x-ray diffraction spectrum of bismuth doping phosphoric acid barium of the present invention; Spectral line adopts Japanese RigakuD/max-IIIA X-ray diffractometer to measure, test voltage 40kV, and 1.2 °/min of sweep velocity, test current 40mA, selects Cu-Ka1 X ray, and wavelength is
as shown in Figure 1, X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi phase, belongs to
trigonal system.Doping 1% bismuth, does not affect the formation of crystal, adds excessive barium in proportioning, be beneficial to crystal formation, as shown in Figure 1.
Fig. 2 is the typical fluorescence spectrum that 260nm of the present invention excites lower bismuth doping phosphoric acid barium; Adopt Edinburgh, Britain FLS 920 stable states and transient state fluorescence spectrophotometer to measure, xenon lamp power is 450 watts, detector is Japanese Hamamatsu refrigeration mode R928P photomultiplier (operating voltage-1250 volt), and data gathering integral time is 0.2 second, and scanning step is 1nm.As shown in Figure 2, this fluorescent material excites the lower yellow fluorescence that can produce peak position and be positioned at 578nm at 260nm.This fluorescence covers the broad spectral region of 400-800nm, fluorescence halfwidth 209nm, and chromaticity coordinates is (0.424,0.460).
Fig. 3 is the ultraviolet region excitation spectrum of bismuth doping phosphoric acid barium of the present invention, corresponding emission wavelength 578nm; Adopt Edinburgh, Britain FLS 920 stable states and transient state fluorescence spectrophotometer to measure, xenon lamp power is 450 watts, detector is Japanese Hamamatsu refrigeration mode R928P photomultiplier (operating voltage-1250 volt), and data gathering integral time is 0.2 second, and scanning step is 1nm.As shown in Figure 3, the excitation spectrum of corresponding 578nm fluorescence covers the absorption in 220~300nm interval, and peak position is positioned at 260nm.
Fig. 4 is the fluorescence decay curve of bismuth doping phosphoric acid barium of the present invention, and corresponding excitation wavelength is 260nm, and emission wavelength is 578nm; Adopt Edinburgh, Britain FLS 920 stable states and transient state fluorescence spectrophotometer to measure, microsecond pulse xenon lamp mean power is 60 watts, repetition rate is made as 100Hz, and detector is Japanese Hamamatsu refrigeration mode R928P photomultiplier (operating voltage-1250 volt).As shown in Figure 4, the present embodiment gained bismuth doping phosphoric acid barium yellow fluorescent material, the fluorescence decay under wavelength 260nm excites, 578nm fluorescence lifetime is 21.8 μ s.
Rare earth ion Dy
3+, Sm
3+also can realize Huang or orange light emission, but be discrete narrow line, Eu
2+nitrogen (oxygen) compound of doping also can realize yellow emission, but the synthetic High Temperature High Pressure that needs.The present embodiment, using bismuth as active ions, is doped into barium phosphate crystal under normal pressure, has made bismuth doping phosphoric acid barium yellow fluorescent material, under ultraviolet excitation, can realize " rare earth ion Dy
3+, Sm
3+can not realize " the transmitting of broad yellow fluorescence, this material can be used for conventional fluorescent, also can with the compound special source of preparing of ultraviolet LED chip.
Embodiment 2
Choose hydrated barta, ammonium hydrogen phosphate and bismuth meal are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.00, y=0.0001, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 3 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 400 ° of C pre-burnings 10 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1000 ° of C of temperature, fire 10 hours, the sample after firing is taken out, after being ground, under atmosphere of hydrogen, fire for the second time, control 1500 ° of C of temperature, fire 0.5 hour; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, diffraction peak intensity and slightly difference of embodiment 1.After testing, the spectral quality of the present embodiment gained fluorescent material is with similar in embodiment 1.
Embodiment 3
Choose barium oxide, phosphoric acid and bismuth chloride are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.50, y=0.10, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 0.4 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 800 ° of C pre-burnings 2 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1500 ° of C of temperature, fire 2 hours, the sample after firing is taken out, after being ground, under carbon monoxide, fire for the second time, control 1500 ° of C of temperature, fire 2 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, only diffraction peak intensity and slightly difference of embodiment 1.The spectral quality of fluorescent material is with similar in embodiment 1.
Embodiment 4
Choose nitrate of baryta, Vanadium Pentoxide in FLAKES and Bismuth Subcarbonate are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.20, y=0.01, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 1 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 600 ° of C pre-burnings 5 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1000 ° of C of temperature, fire 10 hours, the sample after firing is taken out, after being ground, under nitrogen and hydrogen mixture, fire for the second time, control 1000 ° of C of temperature, fire 2 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, only diffraction peak intensity and slightly difference of embodiment 1.The spectral quality of fluorescent material is with similar in embodiment 1.
Embodiment 5
Choose barium oxalate, primary ammonium phosphate and bismuthous oxide bismuth trioxide are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.10, y=0.01, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 1 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 500 ° of C pre-burnings 10 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1300 ° of C of temperature, fire 5 hours, the sample after firing is taken out, after being ground, under air, fire for the second time, control 1300 ° of C of temperature, fire 5 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, only diffraction peak intensity and slightly difference of embodiment 1.The spectral quality of fluorescent material is with similar in embodiment 1.
Embodiment 6
Choose barium acetate, primary ammonium phosphate and bismuthous oxide bismuth trioxide are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, and wherein x=3.10, y=0.01, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 1 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 500 ° of C pre-burnings 10 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1300 ° of C of temperature, fire 5 hours, the sample after firing is taken out, after being ground, under air, fire for the second time, control 1300 ° of C of temperature, fire 5 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, only diffraction peak intensity and slightly difference of embodiment 1.The spectral quality of fluorescent material is with similar in embodiment 1.
Embodiment 7
Choose barium carbonate, primary ammonium phosphate and bismuthous oxide bismuth trioxide are made starting raw material, in molar ratio barium: phosphorus: bismuth=x (1-y): 2: xy, wherein x=3.10,3.15,3.20,3.30, y=0.01, takes respectively three kinds of raw materials, and controlling mixture total weight is 20 grams.20 grams of mixtures, after mixing, are put into corundum crucible, then crucible are put into high-temperature electric resistance furnace.Controlling temperature rise rate is 1 ° of C/ minute, controls phosphorus compound decomposition rate, prevents that mixture from overflowing from crucible, and sample was 500 ° of C pre-burnings 10 hours.Sample after pre-burning is taken out, after being again ground, put into crucible, under air, fire for the first time, control 1300 ° of C of temperature, fire 5 hours, the sample after firing is taken out, after being ground, under air, fire for the second time, control 1300 ° of C of temperature, fire 5 hours; Then be chilled to room temperature with stove and obtain required yellow fluorescent material.X-ray diffraction analysis shows that it is Ba
3(PO
4)
2: Bi crystalline phase, diffraction peak position is in the same manner as in Example 1, only diffraction peak intensity and slightly difference of embodiment 1.The spectral quality of fluorescent material is with similar in embodiment 1.
Fig. 5 is that the present embodiment gained bismuth doping phosphoric acid barium yellow fluorescent material 260nm excites lower sample barium: the fluorescence spectrum of phosphorus: bismuth=x (1-y): 2: xy (wherein x=3.10,3.15,3.20,3.30, y=0.01). curve 1:x=3.10; Curve 2:x=3.15; Curve 3:x=3.20; Curve 4:x=3.30.Adopt Edinburgh, Britain FLS 920 stable states and transient state fluorescence spectrophotometer to measure, xenon lamp power is 450 watts, detector is Japanese Hamamatsu refrigeration mode R928P photomultiplier (operating voltage-1250 volt), and data gathering integral time is 0.2 second, and scanning step is 1nm.As shown in Figure 5, with the increase of x, the luminous intensity of sample first increases, and reaches maximum to x=3.15, continues to increase luminous intensity and reduces, and fluorescence lifetime is between 21.18~21.81 microseconds.
Above-described embodiment is preferably embodiment of the present invention; but embodiments of the present invention are not restricted to the described embodiments; other any do not deviate from change, the modification done under spirit of the present invention and principle, substitutes, combination, simplify; all should be equivalent substitute mode, within being included in protection scope of the present invention.