CN115323477A - Bismuth tungstate monocrystal and preparation method thereof - Google Patents
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Abstract
The invention discloses a bismuth tungstate monocrystal and a preparation method thereof, wherein the preparation method is a fluxing agent method and comprises the following steps: mixing tungsten oxide powder and bismuth oxide powder, and carrying out high-temperature solid-phase reaction to generate bismuth tungstate polycrystal; adding a fluxing agent into the bismuth tungstate polycrystal, heating and melting, keeping the temperature constant for a period of time, carrying out programmed cooling to a preset temperature, and naturally cooling to room temperature to obtain the bismuth tungstate monocrystal. According to the invention, a flux method is adopted, the flux is mixed with the prepared bismuth tungstate polycrystal, the bismuth tungstate polycrystal is heated and melted for a certain time, and the growth of the bismuth tungstate monocrystal is controlled by cooling, so that the bismuth tungstate monocrystal can be used as a scintillation crystal to be applied to the field of nuclear radiation detection, and the problem that the bismuth tungstate polycrystal powder cannot be used as the scintillation crystal to be applied to the field of nuclear radiation detection due to the configuration defect of the bismuth tungstate polycrystal powder is solved. The preparation method has the advantages of simple process, easily obtained raw materials, lower cost and easy realization, and can provide beneficial reference for preparing large-size bismuth tungstate single crystals.
Description
Technical Field
The invention relates to the field of scintillation materials, in particular to a bismuth tungstate monocrystal and a preparation method thereof.
Background
In recent years, with the rapid development of nuclear physics, nuclear medicine and high-energy physics, the demand for high-quality and high-performance inorganic scintillation crystals is more and more urgent. Tungstate series scintillation crystals are important inorganic scintillation materials, and lead tungstate and sodium bismuth tungstate which are newly researched from early chromium tungstate and zinc tungstate to scintillation crystals with excellent performance. The tungstate crystal has the advantages of high density, high luminous efficiency, strong irradiation resistance, no deliquescence, low price and the like, and is widely applied to the fields of medical treatment, security inspection, high-energy physics and the like.
Bismuth tungstate (Bi) 2 WO 6 ) Is represented by the structural formula Bi 2 A n-1 B n O 3n+3 (A = Ca, sr, ba, pb, bi, na, K and B = Ti, nb, ta, mo, W, fe) is one of the simplest oxides in the Auvillius family, with the crystal structure being octahedral WO 4 2- And Bi 2 O 2 2 + The ion layers are mutually alternated to form a lamellar structure. Bismuth tungstate has physical and chemical properties such as piezoelectricity, ferroelectricity, pyroelectricity and catalysis, so that the bismuth tungstate has wide application in the fields of ferromagnetic materials, photocatalysis and the like, but the application of the bismuth tungstate as a scintillation crystal is not reported yet. At present, the preparation method of bismuth tungstate crystal materials mainly comprises a solid-phase sintering method, a precipitation method, a solvothermal method, a sol-gel method, an ultrasonic chemical method, a hydrothermal method, a microemulsion method and the like, and bismuth tungstate powder with different shapes and different luminescence properties can be prepared by controlling synthesis conditions and an element doping method. However, the bismuth tungstate polycrystalline powder has small particles and is easy to agglomerate, and the bismuth tungstate polycrystalline powder cannot be used as a scintillation crystal to be applied to the field of nuclear radiation detection like a single crystal due to the configuration defect of the bismuth tungstate polycrystalline powder, and the preparation method of the bismuth tungstate crystal material is yet to be further researched.
Accordingly, the prior art is yet to be improved and developed.
Disclosure of Invention
In view of the defects of the prior art, the invention aims to provide a bismuth tungstate monocrystal and a preparation method thereof, and aims to solve the problem that bismuth tungstate polycrystalline powder obtained by the existing preparation method cannot be used as a scintillation crystal for the field of nuclear radiation detection due to configuration defects.
The technical scheme of the invention is as follows:
in a first aspect of the present invention, there is provided a bismuth tungstate (Bi) 2 WO 6 ) A method for producing a single crystal, wherein the production method is a flux method, comprising the steps of:
mixing tungsten oxide powder and bismuth oxide powder, and carrying out high-temperature solid-phase reaction to generate bismuth tungstate polycrystal;
adding a fluxing agent into the bismuth tungstate polycrystal, heating and melting, keeping the temperature constant for a period of time, carrying out programmed cooling to a preset temperature, and naturally cooling to room temperature to obtain the bismuth tungstate monocrystal.
Optionally, the temperature of the solid phase reaction is 600-700 ℃, and the time of the solid phase reaction is 10-12 h.
Optionally, the heating and melting temperature is 1000 ℃, and the constant temperature time is 5-6 h.
Optionally, the programmed temperature reduction is performed by firstly reducing the temperature from 1000 ℃ to 940 ℃ at a rate of 10 ℃/h, and then reducing the temperature from 940 ℃ to 840 ℃ at a rate of 2 ℃/h.
Optionally, the tungsten oxide powder has a particle size <25 μm and the bismuth oxide powder has a particle size <25 μm.
Optionally, the molar ratio of the tungsten oxide powder to the bismuth oxide powder is (1-1.05): (1-1.05).
Optionally, the flux is selected from one or more of sodium chloride, lithium metaborate, lithium borate, and sodium borate.
Optionally, the molar ratio of the fluxing agent to the bismuth tungstate polycrystal is 1:1-3:7.
In a second aspect of the invention, a bismuth tungstate monocrystal is provided, wherein the bismuth tungstate monocrystal is prepared by the preparation method.
Optionally, the chemical formula of the bismuth tungstate single crystal is Bi 2 WO 6 Belonging to the orthorhombic system, the space group is Pca2 1 The unit cell parameter is
Has the beneficial effects that: in the invention, tungsten oxide powder and bismuth oxide powder are mixed and then react with high Wen Gu to generate bismuth tungstate polycrystal, then fluxing agent is added into the bismuth tungstate polycrystal to dissolve bismuth tungstate into the low-melting-point fluxing agent to form molten saturated solution, and then the molten saturated solution is in a supersaturated state by a programmed cooling method to further separate out bismuth tungstate monocrystal. The prepared bismuth tungstate single crystal can be used as a scintillation crystal to be applied to the field of nuclear radiation detection, and the problem that the bismuth tungstate polycrystalline powder obtained by the existing preparation method cannot be used as the scintillation crystal to be applied to the field of nuclear radiation detection due to the configuration defect of the bismuth tungstate polycrystalline powder is solved. The preparation method has the advantages of simple process, easily obtained raw materials, lower cost and easy realization, and can provide beneficial reference for preparing large-size bismuth tungstate single crystals.
Drawings
FIG. 1a shows bismuth tungstate (Bi) in example 1 of the present invention 2 WO 6 ) The morphology of the single crystal, and FIG. 1b is a structural diagram of the bismuth tungstate single crystal in example 1 of the present invention.
FIG. 2 is an XRD pattern of a bismuth tungstate single crystal in examples 1 and 2 of the present invention.
FIG. 3 is a fluorescence emission spectrum of a bismuth tungstate single crystal in example 1 of the present invention.
Detailed Description
The invention provides a bismuth tungstate monocrystal and a preparation method thereof, and the invention is further explained in detail below in order to make the purpose, technical scheme and effect of the invention clearer and more clear. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
The embodiment of the invention provides a preparation method of a bismuth tungstate monocrystal, wherein the preparation method is a fluxing agent method and comprises the following steps:
s1, mixing tungsten oxide (WO) 3 ) Powder and bismuth oxide (Bi) 2 O 3 ) After the powders are mixed, carrying out high-temperature solid-phase reaction to generate bismuth tungstate polycrystal;
s2, adding a fluxing agent into the bismuth tungstate polycrystal, heating and melting, keeping the temperature constant for a period of time, carrying out programmed cooling, and naturally cooling to room temperature to obtain the bismuth tungstate (Bi) 2 WO 6 ) And (3) single crystal.
The flux method is also called flux method or molten salt method, and is a method for growing crystals from a molten salt flux at high temperature. In this example, bismuth tungstate (Bi) was grown by flux method 2 WO 6 ) Specifically, tungsten oxide powder and bismuth oxide powder are subjected to high-temperature solid-phase reaction to synthesize bismuth tungstate polycrystal, then fluxing agent is added to dissolve the bismuth tungstate polycrystal into the low-melting-point fluxing agent to form molten saturated solution, and then the molten saturated solution is in a supersaturated state through slow temperature reduction, so that the bismuth tungstate monocrystal is precipitated and grown. The bismuth tungstate monocrystal can be used as a scintillation crystal to be applied to the field of nuclear radiation detection, and the problem that bismuth tungstate polycrystalline powder obtained by the existing preparation method cannot be used as the scintillation crystal to be applied to the field of nuclear radiation detection due to the configuration defect of the bismuth tungstate polycrystalline powder is solved. The preparation method provided by the embodiment has the advantages of simple process, easily obtained raw materials, lower cost and easy realization, and can provide beneficial reference for preparing large-size bismuth tungstate single crystals.
In step S1, in one embodiment, the tungsten oxide powder and the bismuth oxide powder are mixed and then sufficiently ground, so that the solid-phase synthesis reaction of bismuth tungstate is more complete. The particle size of the tungsten oxide powder after grinding is <25 μm, and the particle size of the bismuth oxide powder is <25 μm.
In one embodiment, the step of mixing the tungsten oxide powder and the bismuth oxide powder and then performing a high-temperature solid-phase reaction to produce the bismuth tungstate polycrystal specifically comprises:
according to Bi 2 WO 6 Of tungsten oxide (WO) 3 ) Powder and bismuth oxide (Bi) 2 O 3 ) And uniformly mixing and grinding the powder, placing the powder in a first crucible, and then placing the crucible in a box-type furnace to perform high-temperature solid-phase reaction to generate bismuth tungstate polycrystal.
In one embodiment, the molar ratio of the tungsten oxide powder to the bismuth oxide powder is (1 to 1.05): (1-1.05).
In a further embodiment, the molar ratio of the tungsten oxide powder to the bismuth oxide powder is 1:1.
in one embodiment, the first crucible is selected from one of a ceramic crucible, a corundum crucible, and a platinum crucible, but is not limited thereto. The material of the crucible can be selected according to actual needs. In a further embodiment, the first crucible is selected from platinum crucibles, which have a low impact on the reaction product, which enable a pure reaction product to be obtained, with a low content of impurities.
In one embodiment, the first crucible has a volume size of one of 30mL, 50mL, 75mL, and 100mL, but is not limited thereto. It is understood that the size of the crucible can be selected according to actual needs, and is not limited to the volume size in the present embodiment.
In one embodiment, the temperature of the solid phase reaction is 600 to 700 ℃, and the time of the solid phase reaction is 10 to 12 hours. Under the temperature and the time, tungsten oxide and bismuth oxide powder are synthesized into bismuth tungstate (Bi) through Wen Gu phase 2 WO 6 ) And (4) polycrystallization.
In some embodiments, the temperature of the solid phase reaction may be 600 ℃, 620 ℃, 650 ℃, 680 ℃, 700 ℃, and the like.
In some embodiments, the time for the solid phase reaction may be 10h, 11h, 12h, and the like.
In the step S2, adding a fluxing agent into the bismuth tungstate polycrystal, heating for melting, keeping the temperature constant for a period of time to completely melt the melt, then slowly cooling the melt by a program, and naturally cooling the melt to room temperature to obtain the bismuth tungstate (Bi) 2 WO 6 ) And (3) single crystal.
In one embodiment, the molar ratio of the fluxing agent to the bismuth tungstate polycrystal is 1:1-3:7. The proportion can fully play the role of the fluxing agent and prepare high-quality bismuth tungstate single crystals.
In a further embodiment, the molar ratio of the flux to the polycrystalline bismuth tungstate is 1:1 or 3:7.
In one embodiment, a fluxing agent is added into the bismuth tungstate polycrystal, the bismuth tungstate polycrystal is ground uniformly, the bismuth tungstate polycrystal is placed in a second crucible, heated and melted, kept at a constant temperature for a period of time, so that the melt is completely melted, then slowly cooled in a program mode, and naturally cooled to the room temperature, and the bismuth tungstate monocrystal is obtained.
In one embodiment, the second crucible is selected from a platinum crucible. In the growth stage of the bismuth tungstate single crystal, a platinum crucible is selected, so that the pollution of the crucible to the crystal can be avoided.
In one embodiment, the volume of the platinum crucible is one of 30mL, 50mL, 75mL, and 100mL, but is not limited thereto.
In one embodiment, the flux is selected from one or more of sodium chloride, lithium metaborate, lithium borate, and sodium borate, but is not limited thereto. By way of example, the fluxing agent may be selected from lithium metaborate, the fluxing agent may be selected from lithium borate, the co-solvent may be selected from sodium chloride and lithium metaborate, and the fluxing agent may be selected from sodium chloride, lithium metaborate and sodium borate. The addition of the fluxing agent can reduce the melting point of the system, and the fluxing agent (one or more of sodium chloride, lithium metaborate, lithium borate and sodium borate) is a non-toxic environment-friendly material and is easy to obtain.
In a further embodimentWherein the sodium borate is sodium tetraborate (Na) 2 B 4 O 7 ) The lithium borate is lithium tetraborate (Li) 2 B 4 O 7 )。
In one embodiment, the heating and melting temperature is 1000 ℃, and the constant temperature time is 5-6 h. The bismuth tungstate polycrystal and the fluxing agent are heated for 5 to 6 hours at the temperature of 1000 ℃, and uniform molten liquid can be obtained.
In one embodiment, the programmed cooling procedure is to cool from 1000 ℃ to 940 ℃ at a rate of 10 ℃/h, then from 940 ℃ to 840 ℃ at a rate of 2 ℃/h, and finally cool naturally to room temperature. In the embodiment, programmed cooling is adopted, the temperature is reduced from 1000 ℃ to 940 ℃ at the rate of 10 ℃/h, and 940 ℃ is the phase transition temperature of the bismuth tungstate, the crystal growth temperature is set to be lower than the phase transition temperature, and the quality and the size of the bismuth tungstate single crystal are improved by adopting a slow cooling means (the cooling rate is 2 ℃/h).
In one embodiment, adding a flux to the bismuth tungstate polycrystal, and growing the bismuth tungstate crystal by the flux method further includes: separating the prepared bismuth tungstate monocrystal from a platinum crucible by using concentrated nitric acid, washing by using deionized water and drying to obtain bismuth tungstate (Bi) 2 WO 6 ) And (3) single crystal.
In one embodiment, the concentration of the concentrated nitric acid is 5 to 6mol/L. By way of example, the concentrated nitric acid has a concentration of 5mol/L, 5.5mol/L, 6mol/L, and the like.
The embodiment of the invention also provides a bismuth tungstate monocrystal, wherein the bismuth tungstate monocrystal is prepared by the preparation method provided by the embodiment of the invention.
In one embodiment, the chemical formula of the bismuth tungstate single crystal is Bi 2 WO 6 Belonging to the orthorhombic system, the space group is Pca2 1 Unit cell parameter of
The bismuth tungstate monocrystal is a scintillation crystal, the fluorescence emission spectrum of the bismuth tungstate monocrystal is 420-474 nm, the luminescence peak position of the bismuth tungstate monocrystal is 450nm, and the bismuth tungstate monocrystal can be applied to the field of nuclear radiation detection.
The following is a detailed description of specific examples.
Example 1
1.623g (0.007 mol) of WO are weighed out 3 And 2.362g (0.007 mol) of Bi 2 O 3 Fully and uniformly grinding in an agate mortar, then putting into a 30mL platinum crucible, putting into a box furnace, and carrying out solid phase high temperature reaction at 650 ℃ for 10h to obtain the bismuth tungstate polycrystal.
0.507g (0.003 mol) of Li are weighed out 2 B 4 O 7 Uniformly mixing the bismuth tungstate crystal and the prepared bismuth tungstate polycrystal, then placing the bismuth tungstate crystal into a 30mL platinum crucible, placing the platinum crucible into a box furnace, keeping the temperature of the platinum crucible at 1000 ℃ for 5 hours, then reducing the temperature to 940 ℃ at the speed of 10 ℃/h, reducing the temperature from 940 ℃ to 840 ℃ at the speed of 2 ℃/h, and finally naturally cooling the bismuth tungstate crystal to the room temperature to obtain the bismuth tungstate crystal.
Separating the prepared bismuth tungstate monocrystal from a platinum crucible by using 5mol/L nitric acid, and washing and drying by using deionized water to obtain the bismuth tungstate monocrystal.
The morphology and structure of the bismuth tungstate monocrystal are respectively shown in figures 1a and 1 b. FIG. 2 is an XRD spectrum, and the prepared bismuth tungstate is in an orthorhombic system and has a molecular formula of Bi 2 WO 6 The space group is Pca2 1 Unit cell parameter of
Photoluminescence test was performed on the bismuth tungstate single crystal obtained in example 1 by using a photoluminescence spectrometer, and a photoluminescence spectrum of the bismuth tungstate single crystal is shown in fig. 3, wherein a fluorescence emission spectrum range is 420 to 474nm, and an emission peak position is 450nm.
Example 2
3.246g (0.014 mol) WO is weighed 3 And 4.724g (0.014 mol) Bi 2 O 3 Fully and uniformly grinding in an agate mortar, then putting into a 50mL platinum crucible, putting into a box furnace, and carrying out solid phase high temperature reaction at 650 ℃ for 10h to obtain the bismuth tungstate polycrystal.
1.014g (0.006 mol) of Li were weighed 2 B 4 O 7 Mixing the bismuth tungstate powder with the prepared bismuth tungstate polycrystal uniformly, and then filling the mixture into 50mLPutting the platinum crucible into a box furnace, keeping the temperature of 1000 ℃ for 5h, then reducing the temperature to 940 ℃ at the speed of 10 ℃/h, then reducing the temperature from 940 ℃ to 840 ℃ at the speed of 2 ℃/h, and finally naturally cooling to room temperature to obtain the bismuth tungstate monocrystal.
Separating the prepared bismuth tungstate monocrystal from a platinum crucible by using 5mol/L nitric acid, and washing and drying by using deionized water to obtain the bismuth tungstate monocrystal. The crystal structure is the same as that of the embodiment 1, and is orthorhombic bismuth tungstate; the fluorescence emission spectrum was substantially similar to that of example 1.
Example 3
1.623g (0.007 mol) of WO are weighed out 3 And 2.362g (0.007 mol) of Bi 2 O 3 Fully and uniformly grinding in an agate mortar, then putting into a 30mL platinum crucible, putting into a box furnace, and carrying out solid phase high temperature reaction at 650 ℃ for 10h to obtain the bismuth tungstate polycrystal.
0.604g (0.003 mol) anhydrous Na was weighed 2 B 4 O 7 Uniformly mixing the bismuth tungstate crystal and the prepared bismuth tungstate polycrystal, then placing the bismuth tungstate crystal into a 30mL platinum crucible, placing the platinum crucible into a box furnace, keeping the temperature of the platinum crucible at 1000 ℃ for 5 hours, then reducing the temperature to 940 ℃ at the speed of 10 ℃/h, reducing the temperature from 940 ℃ to 840 ℃ at the speed of 2 ℃/h, and finally naturally cooling the bismuth tungstate crystal to the room temperature to obtain the bismuth tungstate crystal.
Separating the prepared bismuth tungstate monocrystal from a platinum crucible by using 5mol/L nitric acid, and washing and drying by using deionized water to obtain the bismuth tungstate monocrystal. The crystal structure is the same as that of the embodiment 1, and the crystal structure is orthorhombic bismuth tungstate; the fluorescence emission spectrum was substantially similar to that of example 1.
Example 4
3.246g (0.014 mol) WO is weighed 3 And 4.724g (0.014 mol) Bi 2 O 3 Fully and uniformly grinding in an agate mortar, then putting into a 50mL platinum crucible, putting into a box furnace, and carrying out solid phase high temperature reaction at 650 ℃ for 10h to obtain the bismuth tungstate polycrystal.
1.207g (0.006 mol) of anhydrous Na was weighed 2 B 4 O 7 Uniformly mixing the bismuth tungstate powder and the prepared bismuth tungstate polycrystal, then placing the bismuth tungstate powder into a 50mL platinum crucible, placing the platinum crucible into a box furnace, keeping the temperature of the platinum crucible at 1000 ℃ for 5 hours, then reducing the temperature to 940 ℃ at the speed of 10 ℃/h, reducing the temperature from 940 ℃ to 840 ℃ at the speed of 2 ℃/h, and finally naturally coolingCooling to room temperature to obtain the bismuth tungstate monocrystal.
Separating the prepared bismuth tungstate monocrystal from a platinum crucible by using 5mol/L nitric acid, and washing and drying by using deionized water to obtain the bismuth tungstate monocrystal. The crystal structure is the same as that of the embodiment 1, and is orthorhombic bismuth tungstate; the fluorescence emission spectrum was substantially similar to that of example 1.
In conclusion, the invention provides a bismuth tungstate monocrystal and a preparation method thereof. The method adopts a fluxing agent method to grow the bismuth tungstate single crystal, firstly, tungsten oxide powder and bismuth oxide powder are mixed, high-temperature solid phase reaction is carried out to generate bismuth tungstate polycrystal, then the fluxing agent is added, the bismuth tungstate polycrystal is dissolved in the fluxing agent to form uniform molten saturated solution, the molten saturated solution is in a supersaturated state through a slow cooling method, and the precipitation growth of the bismuth tungstate single crystal is controlled. The bismuth tungstate monocrystal can be used as a scintillation crystal in the field of nuclear radiation detection, and the problem that bismuth tungstate polycrystalline powder cannot be used as the scintillation crystal in the field of nuclear radiation detection due to the configuration defect of the bismuth tungstate polycrystalline powder is solved. The preparation method has the advantages of simple process, easily obtained raw materials, lower cost and easy realization, and can provide beneficial reference for preparing large-size bismuth tungstate single crystals.
It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.
Claims (10)
1. A preparation method of bismuth tungstate monocrystal is characterized in that the preparation method is a fluxing agent method and comprises the following steps:
mixing tungsten oxide powder and bismuth oxide powder, and carrying out high-temperature solid-phase reaction to generate bismuth tungstate polycrystal;
adding a fluxing agent into the bismuth tungstate polycrystal, heating and melting, keeping the temperature constant for a period of time, then carrying out programmed cooling to a preset temperature, and naturally cooling to room temperature to obtain the bismuth tungstate monocrystal.
2. The method for preparing bismuth tungstate monocrystal according to claim 1, wherein the temperature of the solid-phase reaction is 600-700 ℃, and the time of the solid-phase reaction is 10-12 h.
3. The method for preparing a bismuth tungstate monocrystal as claimed in claim 1, wherein the temperature of the heating and melting is 1000 ℃, and the time of the constant temperature is 5 to 6 hours.
4. The method of producing a bismuth tungstate monocrystal as claimed in claim 1, wherein the programmed temperature reduction is carried out by first reducing the temperature from 1000 ℃ to 940 ℃ at a rate of 10 ℃/h, and then reducing the temperature from 940 ℃ to 840 ℃ at a rate of 2 ℃/h.
5. The method of producing a bismuth tungstate monocrystal as claimed in claim 1, wherein the tungsten oxide powder has a particle size of <25 μm, and the bismuth oxide powder has a particle size of <25 μm.
6. The method for preparing a bismuth tungstate monocrystal as claimed in claim 1, wherein the molar ratio of the tungsten oxide powder to the bismuth oxide powder is (1 to 1.05): (1-1.05).
7. A method for preparing a bismuth tungstate monocrystal as claimed in claim 1, wherein the flux is one or more selected from sodium chloride, lithium metaborate, lithium borate and sodium borate.
8. The method for preparing the bismuth tungstate monocrystal as claimed in claim 1, wherein the molar ratio of the flux to the bismuth tungstate polycrystal is 1:1-3:7.
9. A bismuth tungstate monocrystal which is characterized by being prepared by the preparation method as claimed in any one of claims 1 to 8.
10. The bismuth tungstate monocrystal of claim 9, wherein the chemical formula of the bismuth tungstate monocrystal is Bi 2 WO 6 Belonging to the orthorhombic system, the space group is Pca2 1 Unit cell parameter of
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107012508A (en) * | 2017-04-26 | 2017-08-04 | 苏州聚康新材料科技有限公司 | A kind of bismuth tungstate porous monocrystalline and preparation method thereof |
| WO2021052257A1 (en) * | 2019-09-17 | 2021-03-25 | 江苏大学 | Black bismuth tungstate photocatalyst, preparation method, and application |
| WO2021169196A1 (en) * | 2020-02-27 | 2021-09-02 | 齐鲁工业大学 | Bismuth tungstate/bismuth sulfide/molybdenum disulfide ternary heterojunction composite material, preparation method therefor, and application thereof |
| CN114561704A (en) * | 2022-01-29 | 2022-05-31 | 临沂大学 | Flux growth method and application of large-size bismuth tungstate crystal |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107012508A (en) * | 2017-04-26 | 2017-08-04 | 苏州聚康新材料科技有限公司 | A kind of bismuth tungstate porous monocrystalline and preparation method thereof |
| WO2021052257A1 (en) * | 2019-09-17 | 2021-03-25 | 江苏大学 | Black bismuth tungstate photocatalyst, preparation method, and application |
| WO2021169196A1 (en) * | 2020-02-27 | 2021-09-02 | 齐鲁工业大学 | Bismuth tungstate/bismuth sulfide/molybdenum disulfide ternary heterojunction composite material, preparation method therefor, and application thereof |
| CN114561704A (en) * | 2022-01-29 | 2022-05-31 | 临沂大学 | Flux growth method and application of large-size bismuth tungstate crystal |
Non-Patent Citations (1)
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| 施洪龙等 编著: "《X-射线粉末衍射和电子衍射-常用实验技术与数据分析》", 中央民族大学出版社, pages: 229 * |
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