Praseodymium ion doped phosphate crystal material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of inorganic functional crystals, and particularly relates to a praseodymium ion doped phosphate crystal material and a preparation method and application thereof. The invention provides a praseodymium ion doped phosphate crystal material. The chemical formula of the praseodymium ion doped phosphate crystal material is as shown in a formula 1: Ba3Y1-x (PO4) 3: xPr, in the formula 1, 0 lt; and x is less than or equal to 0.3. In the praseodymium ion doped phosphate crystal material provided by the invention, yttrium and barium are mixed in the crystal and occupy the same crystallographic lattice, and the crystal lattice is distorted to a certain extent due to disordered occupation, so that the absorption and emission peaks of praseodymium ions are enhanced and widened, and when the crystal is directly pumped by a blue-ray LD (laser diode), the absorption and emission peaks of the praseodymium ions are improved. Efficient visible laser output can be realized; under irradiation or excitation of high-energy rays or particles, the crystal can realize strong ultraviolet and visible light emission, and can be used as a bifunctional crystal in the field of visible laser and radiation detection.

Description

Technical Field

[0001] The invention belongs to the technical field of inorganic functional crystals, and in particular relates to a praseodymium ion-doped phosphate crystal material and a preparation method and application thereof. Background Art

[0002] Lasers in the visible band of 400 to 760 nm are the basic light sources in the fields of storage, display, processing and communication. As a typical representative of rare earth ions, praseodymium ions doped laser crystals can achieve absorption in the blue light region and multi-wavelength emission from green to red light bands, and are important blue-light pumped all-solid-state visible band laser materials. At present, praseodymium ion-doped laser crystals are mainly concentrated in halide crystals represented by fluorides, but the crystals have shortcomings such as difficulty in growth and poor thermal mechanical properties of the crystals themselves, which restricts its application development.

[0003] With the substantial increase in the output power of blue light InGaN semiconductor lasers (LDs), a method of directly outputting visible-band lasers by pumping praseodymium ion-doped oxide laser crystals with blue light LDs has attracted the attention of researchers. At present, blue light LD pumping has been successfully used in Pr:YAlO3, Pr:Y3Al5O 12 、Pr:SrAl 12 O 19 Laser output has been achieved in oxide crystals, but the output power remains at the milliwatt level and needs to be further improved.

[0004] In addition, scintillation crystals are luminescent materials that can produce efficient fluorescent emission under the stimulation of high-energy radiation particles. They have very wide applications in nuclear medicine imaging, industrial non-destructive testing, port safety inspections, environmental monitoring, geological exploration, oil well drilling, high-energy physics, and astronomical space physics.

[0005] Therefore, there is an urgent need to develop dual-functional crystal materials with visible light laser output, high output power and scintillation performance to meet market demand. Summary of the invention

[0006] The purpose of the present invention is to provide a praseodymium ion-doped phosphate crystal material and a preparation method and application thereof. The praseodymium ion-doped phosphate crystal material provided by the present invention can achieve efficient visible laser output with high output power when directly pumped by a blue light LD; at the same time, it has a scintillation performance. Under the irradiation or excitation of high-energy rays or particles, the crystal can achieve strong ultraviolet and visible light emission, and can be used as a dual-function crystal in the field of visible laser and radiation detection.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a praseodymium ion-doped phosphate crystal material, the chemical formula of the praseodymium ion-doped phosphate crystal material is shown in Formula 1:

[0009] Y3 1-x (PO4)3:xPr formula 1;

[0010] In formula 1: 0 <x≤0.3。

[0011] Preferably, the praseodymium ion-doped phosphate crystal material belongs to the cubic system, and the space group is

[0012] Preferably, in Formula 1: 0.01≤x≤0.3.

[0013] Preferably, x in Formula 1 is 0.01, 0.03, 0.04, 0.08, 0.12, 0.16, 0.2 or 0.3.

[0014] The present invention provides a method for preparing the praseodymium ion-doped phosphate crystal material described in the above technical solution, comprising the following steps:

[0015] According to the chemical composition of the praseodymium ion-doped phosphate crystal material, the prepared raw material is sintered twice to obtain Ba3Y 1-x (PO4)3:xPr polycrystalline raw material; the preparation raw materials include praseodymium oxide, yttrium oxide, inorganic barium salt and inorganic phosphate; the two sinterings include a first sintering and a second sintering;

[0016] In a protective gas atmosphere, the Ba3Y 1-x The (PO4)3:xPr polycrystalline raw material is pulled and grown to obtain the praseodymium ion-doped phosphate crystal material.

[0017] Preferably, the first sintering comprises sequentially performing a first grinding, a first tableting and a first calcining;

[0018] The temperature of the first calcination is 1000-1500° C., the time is 15-25 hours, and the heating rate from room temperature to the temperature of the first calcination is 150-250° C. / h.

[0019] Preferably, the second sintering comprises sequentially performing a second grinding, a second tableting and a second calcining;

[0020] The temperature of the second calcination is 1100-1600° C., the time is 20-40 hours, and the heating rate from room temperature to the temperature of the second calcination is 150-250° C. / h.

[0021] Preferably, the temperature for pulling growth is 1750 - 1950 °C, the pulling rate is 0.5 - 3 mm / h, and the rotation speed is 5 - 15 r / min.

[0022] Preferably, after the pulling growth, an initial crystal is obtained, and the method further includes: cooling the initial crystal from the temperature of the pulling growth to room temperature to obtain the praseodymium ion-doped phosphate crystal material; the cooling rate is 5 - 20 °C / h.

[0023] The present invention provides an application of the praseodymium ion-doped phosphate crystal material described in the above technical solution or the praseodymium ion-doped phosphate crystal material prepared by the preparation method described in the above technical solution in visible laser output and radiation detection.

[0024] The present invention provides a praseodymium ion-doped phosphate crystal material, and the chemical formula of the praseodymium ion-doped phosphate crystal material is shown in Formula 1: Ba3Y 1-x (PO4)3:xPr Formula 1; in Formula 1: 0 < x ≤ 0.3. In the praseodymium ion-doped phosphate crystal material (Pr:BYP) provided by the present invention, yttrium element and barium element in the crystal mix and occupy the same crystallographic lattice site. The mixing and disordered occupancy of barium and yttrium cause the crystal lattice to be distorted to a certain extent, thereby enhancing and broadening the absorption and emission peaks of praseodymium ions. When the crystal is directly pumped by a blue light LD, efficient visible laser output can be achieved; moreover, the crystal field of the praseodymium ion-doped phosphate crystal material provided by the present invention does not affect the 4f 1 5d 1 →4f 2 allowed transition, so that the crystal can generate a 5d 1 →4f 2 transition located at 300 nm and f-f emission in the blue to red light band under the excitation of high-energy rays and particles. Therefore, under the irradiation or excitation of high-energy rays or particles, the crystal can achieve strong ultraviolet and visible light emission, showing excellent scintillation characteristics. At the same time, the praseodymium ion-doped phosphate crystal material provided by the present invention has good physical and chemical stability, good thermal properties and low phonon energy. In summary, the praseodymium ion-doped phosphate crystal material provided by the present invention has both good laser and scintillation properties and can be used as a dual-functional crystal in the fields of visible laser and radiation detection.

[0025] The present invention provides a preparation method of the praseodymium ion-doped phosphate crystal material described in the above technical solution, including the following steps: sintering the preparation raw materials twice according to the chemical composition of the praseodymium ion-doped phosphate crystal material to obtain a Ba3Y 1-x (PO4)3:xPr polycrystalline raw material; the preparation raw materials include praseodymium oxide, yttrium oxide, inorganic barium salt and inorganic phosphate; in a protective gas atmosphere, the Ba3Y1-x The (PO4)3:xPr polycrystalline raw material is pulled and grown to obtain the praseodymium ion-doped phosphate crystal material. The present invention adopts the pulling method to grow a large-sized, high-quality single crystal, the crystal growth method is stable, the crystal has stable physical and chemical properties and good optical properties, the raw material is easy to obtain, blue light LD pumping can be used directly, and it can be excited by high-energy rays and particles to achieve scintillation light output and many other advantages, and can be used as a multifunctional crystal material for visible light band laser crystals and scintillation crystals. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 : is the fluorescence spectrum of the polycrystalline powder prepared in Example 1 of the present invention;

[0027] Figure 2 The X-ray powder diffraction pattern of the crystal prepared in Example 2 of the present invention, and the inner figure is a crystal photograph;

[0028] Figure 3 The fluorescence excitation emission spectrum of the crystal prepared in Example 2 of the present invention;

[0029] Figure 4 is the fluorescence decay curve of the crystal prepared in Example 2 of the present invention;

[0030] Figure 5 This is an X-ray excited emission spectrum of the crystal prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0031] The present invention provides a praseodymium ion-doped phosphate crystal material, the chemical formula of the praseodymium ion-doped phosphate crystal material is shown in Formula 1:

[0032] Y3 1-x (PO4)3:xPr formula 1;

[0033] In formula 1: 0 <x≤0.3。

[0034] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0035] In the present invention, x in Formula 1 is preferably 0.01≤x≤0.3, more preferably 0.03≤x≤0.3. In a specific embodiment of the present invention, x in Formula 1 is preferably 0.01, 0.03, 0.04, 0.08, 0.12, 0.16, 0.2 or 0.3, and most preferably 0.12.

[0036] In the present invention, the praseodymium ion-doped phosphate crystal material is a single crystal material, belonging to the cubic system, and the space group is

[0037] In the present invention, the praseodymium ion-doped phosphate crystal material can achieve a variety of laser outputs from cyan to deep red light under the excitation of 450nm blue light. At the same time, the praseodymium ion-doped phosphate crystal material can achieve scintillation light output under the excitation of high-energy rays (such as x-rays, gamma rays and high-energy particles, etc.).

[0038] The present invention provides a method for preparing the praseodymium ion-doped phosphate crystal material described in the above technical solution, comprising the following steps:

[0039] According to the chemical composition of the praseodymium ion-doped phosphate crystal material, the prepared raw material is sintered twice to obtain Ba3Y 1-x (PO4)3:xPr polycrystalline raw material; the preparation raw materials include praseodymium oxide, yttrium oxide, inorganic barium salt and inorganic phosphate;

[0040] In a protective gas atmosphere, the Ba3Y 1-x The (PO4)3:xPr polycrystalline raw material is pulled and grown to obtain the praseodymium ion-doped phosphate crystal material.

[0041] The present invention sintered the raw materials twice according to the chemical composition of the praseodymium ion-doped phosphate crystal material to obtain Ba3Y 1-x (PO4)3:xPr polycrystalline raw material; the raw materials include praseodymium oxide, yttrium oxide, inorganic barium salt and inorganic phosphate. In the present invention, the praseodymium oxide is preferably Pr6O 11 . The yttrium oxide is preferably Y2O3. The inorganic barium salt is preferably barium carbonate (BaCO3). The inorganic phosphate is preferably dihydrogen phosphate, and is preferably ammonium dihydrogen phosphate (NH4H2PO4). In a specific embodiment of the present invention, the above-mentioned preparation raw materials are preferably prepared according to the molar ratio of each element in the chemical formula of the praseodymium ion-doped phosphate crystal material.

[0042] In the present invention, the first sintering preferably includes first grinding, first tableting and first calcining in sequence. The present invention has no special requirements for the specific implementation of the first grinding and first tableting. The first calcination is preferably carried out in a muffle furnace, and the temperature of the first calcination is preferably 1000-1500°C, more preferably 1100-1300°C, and most preferably 1200°C; the time of the first calcination is preferably 15-25h, more preferably 18-22h, and most preferably 20h; the heating rate from room temperature to the temperature of the first calcination is preferably 150-250°C / h, more preferably 200°C / h.

[0043] In the present invention, after the first calcination is completed, the product obtained by the first calcination is preferably cooled to room temperature before the second sintering is performed.

[0044] In the present invention, the second sintering preferably includes second grinding, second tableting and second calcining in sequence. The present invention has no special requirements for the specific implementation of the second grinding and second tableting. The second calcination is preferably carried out in a muffle furnace, and the temperature of the second calcination is preferably 1100-1600°C, more preferably 1200-1500°C; the time of the second calcination is preferably 20-40h, more preferably 25-35h; the heating rate from room temperature to the temperature of the second calcination is preferably 150-250°C / h, more preferably 200°C / h.

[0045] In the present invention, after the second calcination, the product obtained by the second calcination is preferably cooled to room temperature to obtain Ba3Y 1-x (PO4)3:xPr polycrystalline raw material. The Ba3Y1(PO4)3 crystal is used as a seed crystal for subsequent pulling growth.

[0046] Get Ba3Y 1-x After the (PO4)3:xPr polycrystalline raw material is obtained, the Ba3Y 1-x (PO4)3:xPr polycrystalline raw material is pulled and grown to obtain the praseodymium ion-doped phosphate crystal material. 1-x The (PO4)3:xPr polycrystalline raw material is placed in an iridium crucible and placed in a pulling furnace for the pulling growth. The specific size of the iridium crucible is Φ55×50mm 3 . The protective gas is preferably a non-reactive gas, specifically nitrogen or an inert gas, and the inert gas is specifically preferably argon. The temperature of the pulling growth is preferably 1750-1950°C, more preferably 1800-1900°C, and most preferably 1850°C; the pulling speed is preferably 0.5-3mm / h, more preferably 0.8-1.5mm / h, and specifically preferably 1mm / h; the rotation speed is preferably 5-15r / min, more preferably 8-12r / min, and most preferably 10r / min. The rotation speed is the rotation speed of the crystal sample being pulled and grown. In the present invention, during the pulling growth, the heating element is an iridium crucible, and zirconium oxide is used as a heat insulation cover and a heat insulation material.

[0047] In the present invention, an initial crystal is obtained after the pulling growth is completed. The present invention preferably further comprises: cooling the initial crystal from the pulling growth temperature to room temperature after pulling the initial crystal away from the liquid surface to obtain the praseodymium ion-doped phosphate crystal material; the cooling rate is preferably 5 to 20°C / h.

[0048] The present invention provides the application of the praseodymium ion-doped phosphate crystal material described in the above technical solution or the praseodymium ion-doped phosphate crystal material prepared by the preparation method described in the above technical solution in visible laser output and radiation detection.

[0049] In the present invention, the praseodymium ion-doped phosphate crystal material can realize multiple wavelength emission from cyan to deep red light under the excitation of 450nm blue light. At the same time, the praseodymium ion-doped phosphate crystal material can realize scintillation light output under the excitation of high-energy rays (such as x-rays, gamma rays and high-energy particles, etc.).

[0050] In the present invention, the praseodymium ion-doped phosphate crystal material is preferably applied to the output of 470-500nm cyan laser, 590-620nm orange laser and 630-660nm red laser.

[0051] In the present invention, the praseodymium ion-doped phosphate crystal material is preferably used for scintillation luminescence under high-energy ray irradiation or excitation. The high-energy ray irradiation or excitation preferably includes excitation by x-rays, gamma rays and high-energy particles.

[0052] The beneficial effects that the present invention can produce include:

[0053] The praseodymium ion-doped phosphate crystal provided by the present invention has a disordered structure of the crystal due to the mixed occupancy of barium and yttrium, so that the absorption peak and emission peak of the praseodymium ion are broadened to a great extent, and is very suitable for blue light LD pumping to achieve laser output.

[0054] The praseodymium ion doped phosphate crystal provided by the present invention has no effect on the praseodymium ion 4f 1 5d 1 →4f 2 Allowing transitions, the crystal can produce 5d at 300nm under the stimulation of high-energy rays and particles 1 →4f 2 Transition and ff emission in the cyan to red light band.

[0055] The praseodymium ion-doped phosphate laser crystal provided by the present invention can be grown into a single crystal with a larger size and good quality by a pulling method. The crystal growth process is stable, the crystal has stable physical and chemical properties and good optical properties, the raw materials are easily available, blue light LD pumping can be used directly, and it can be excited by high-energy rays and particles to achieve scintillation light output, etc., and can be used as a potential multifunctional crystal material for visible light band laser crystals and scintillation crystals.

[0056] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0057] Example 1

[0058] In this example, Ba3Y is synthesized by solid phase sintering. 1-x (PO4)3:xPr polycrystalline powder, the specific method comprises:

[0059] According to the chemical formula Ba3Y 1-x The molar ratio of each substance in (PO4)3:xPr (x = 0.01, 0.04, 0.08, 0.12, 0.16, 0.20) is accurately weighed Ba2CO3, Y2O3, Pr6O 11 Mix and grind evenly with NH4H2PO4, press into a corundum crucible, heat to 1200℃ at a rate of 200℃ / h in a muffle furnace, calcine at 1200℃ for 20h, take out and grind again, press into a tablet, heat to 1300℃ at a rate of 200℃ / h, calcine at 1300℃ for 20h, and obtain Ba3Y 1-x (PO4)3:xPr polycrystalline powder. Test the fluorescence spectrum of polycrystalline powder, see Figure 1 It can be seen that with the increase of praseodymium ion doping concentration, the emission intensity first increases and then decreases, and the emission intensity is strongest when the praseodymium ion concentration is 12at.% (x=0.12).

[0060] Example 2

[0061] In this embodiment, Ba3Y is grown by the Czochralski method. 0.88 The specific preparation process of (PO4)3:0.12Pr crystal is as follows:

[0062] According to the chemical formula Ba3Y 0.88 The molar ratio of each substance in (PO4)3:0.12Pr (12%Pr:BYP) is accurately weighed Pr6O 11 , Y2O3, BaCO3 and NH4H2PO4 were mixed and ground evenly, pressed into tablets, heated to 1200℃ at a rate of 200℃ / h in a muffle furnace, calcined at 1200℃ for 20h, taken out and ground again, pressed into tablets, heated to 1300℃ at a rate of 200℃ / h, and calcined at 1300℃ for 20h. The synthesized samples were loaded into a Φ55×50mm 3 The iridium crucible was placed in a pulling furnace. The heating element was an iridium crucible, and zirconium oxide was used as a heat insulation cover and insulation material. The pulling method was adopted in a N2 atmosphere. The growth temperature was 1850℃, the pulling speed was 1mm / h, and the crystal speed was 10rpm / min. After the growth was completed, the crystal was slowly pulled away from the liquid surface and cooled to room temperature at a rate of 10℃ / h. A crystal with a size of Φ15×25mm was grown. 3The single crystal of high-quality 12% Pr:BYP crystal was obtained. Some crystal samples were ground and sieved and then tested for X-ray diffraction spectrum. The results showed that the doping of praseodymium ions did not affect the crystal structure.

[0063] Take a 12% Pr:BYP crystal sample and process it into 3×3×2mm 3 The spectral performance of the slice was tested. Figure 2 , Figure 3 and Figure 4 As shown in the figure, 12% Pr:BYP crystals exhibit strong emission peaks at 482nm, 610nm, and 642nm, and the half-peak widths are 12.6nm, 15.5nm, and 7.7nm, respectively. These three strong and wide emission peaks indicate that Pr:BYP crystals have the potential to achieve cyan, orange, and red laser output.

[0064] The processed crystal material was subjected to emission spectroscopy under X-ray excitation at different powers. The test results are as follows: Figure 5 As shown in the figure, the intensity of the three main emission peaks increases with the increase of X-ray power. The results show that Pr:BYP crystals have great application prospects in radiation detection.

[0065] In summary, the present invention uses the pulling method to grow praseodymium ion-doped barium yttrium phosphate crystals, in which praseodymium ions are used as activation ions to not only achieve 470-500nm cyan light, 590-620nm orange light and 630-660nm red light emission, but also achieve strong visible light reflection under the irradiation or excitation of high-energy rays or particles. The crystal of the present invention can achieve laser output and scintillation light output in the visible light band, and has broad application prospects in the fields of scientific research, industrial manufacturing and military fields.

[0066] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A praseodymium ion-doped phosphate crystal material, characterized in that: The chemical formula of the praseodymium ion-doped phosphate crystal material is shown in Formula 1: Y3 1-x (PO4)3:xPr formula 1; In formula 1: 0 <x≤0.3。 2. The praseodymium ion-doped phosphate crystalline material according to claim 1, characterized in that: The praseodymium ion-doped phosphate crystal material belongs to the cubic system, and the space group is 3. The praseodymium ion-doped phosphate crystalline material according to claim 1 or 2, characterized in that: In formula 1: 0.01≤x≤0.

3.

4. The praseodymium ion-doped phosphate crystalline material according to claim 3, characterized in that: In Formula 1, x is 0.01, 0.03, 0.04, 0.08, 0.12, 0.16, 0.2 or 0.

3.

5. The method for preparing the praseodymium ion-doped phosphate crystal material according to any one of claims 1 to 4, characterized in that: The following steps are involved: According to the chemical composition of the praseodymium ion-doped phosphate crystal material, the prepared raw material is sintered twice to obtain Ba3Y 1-x (PO4)3:xPr polycrystalline raw material; the preparation raw materials include praseodymium oxide, yttrium oxide, inorganic barium salt and inorganic phosphate; the two sinterings include a first sintering and a second sintering; In a protective gas atmosphere, the Ba3Y 1-x The (PO4)3:xPr polycrystalline raw material is pulled and grown to obtain the praseodymium ion-doped phosphate crystal material.

6. The preparation method according to claim 5, characterized in that: The first sintering includes sequentially performing first grinding, first tableting and first calcining; The temperature of the first calcination is 1000-1500° C., the time is 15-25 hours, and the heating rate from room temperature to the temperature of the first calcination is 150-250° C. / h.

7. The preparation method according to claim 5 or 6, characterized in that: The second sintering includes sequentially performing a second grinding, a second tableting and a second calcining; The temperature of the second calcination is 1100-1600° C., the time is 20-40 hours, and the heating rate from room temperature to the temperature of the second calcination is 150-250° C. / h.

8. The preparation method according to claim 5, characterized in that: The pulling growth temperature is 1750-1950° C., the pulling speed is 0.5-3 mm / h, and the rotation speed is 5-15 r / min.

9. The preparation method according to claim 5 or 8, characterized in that: After the pulling growth is completed, the initial crystal is obtained, and the process also includes: cooling the initial crystal from the pulling growth temperature to room temperature to obtain the praseodymium ion-doped phosphate crystal material; the cooling rate is 5 to 20° C. / h.

10. Use of the praseodymium ion-doped phosphate crystal material according to any one of claims 1 to 4 or the praseodymium ion-doped phosphate crystal material prepared by the preparation method according to any one of claims 5 to 9 in visible laser output and radiation detection.

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