Nitrophosphate phosphor for solid state lighting and method of manufacture

Abstract

Disclosed is a method of forming a nitrophosphate, the method comprising: forming a precursor mixture by combining a metal source material, a phosphorus source material, and a nitrogen source material; and heating the precursor mixture at a maximum temperature between 800 °C and 1300 °C in an atmosphere comprising nitrogen at a pressure between 2 MPa and 500 MPa.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to European Patent Application No. 20162632.2 entitled “NITRIDOPHOSPHATE PHOSPHORS FOR SOLID STATE LIGHTING AND METHOD OF PRODUCTION”, filed on March 12, 2020, the entire contents of which are incorporated herein by reference. Background Technology

[0003] Semiconductor light-emitting diodes and laser diodes (collectively referred to herein as "LEDs") are among the most efficient light sources currently available. The emission spectrum of an LED typically exhibits a single, narrow peak at a wavelength determined by the device's structure and the composition of the semiconductor materials it constitutes. By appropriately selecting the device structure and material system, LEDs can be designed to operate at ultraviolet, visible, or infrared wavelengths.

[0004] LEDs can be combined with one or more wavelength conversion materials (generally referred to herein as "phosphors") that absorb the light emitted by the LED and, in response, emit longer wavelength light. For such phosphor-converting LEDs ("pcLEDs"), the proportion of light emitted by the LED that is absorbed by the phosphor depends on the amount of phosphor material in the optical path of the light emitted by the LED, for example, on the concentration of phosphor material in a phosphor layer disposed on or around the LED and the thickness of that layer.

[0005] Phosphor-converted LEDs can be designed such that all the light emitted by the LED is absorbed by one or more phosphors, in which case the emission from the pcLED originates entirely from the phosphor. In this case, for example, the phosphor can be selected to emit light in a narrow spectral region that is not directly generated by the LED.

[0006] Alternatively, a pcLED can be designed such that only a portion of the light emitted by the LED is absorbed by the phosphor. In this case, the emission from the pcLED is a mixture of light emitted by the LED and light emitted by the phosphor. By appropriately selecting the LED, phosphor, and phosphor components, a pcLED can be designed to emit white light, for example, with a desired color temperature and desired color rendering properties.

[0007] Nitridophosphates include compounds with the MPNOX structure, where M is a metal and X is a halide. SD KloB and W. Schnick have recently provided a detailed review of such nitridophosphates. Nitridophosphates: A Success Story of Nitride Synthesis Angew. Chem. Int. Ed., 2019, 58, 7933-7944. Marchuk et al. ( Nontypical Luminescence Properties and Structural Relation of Ba 3 P 5 N 10 X:Eu 2+ (X = Cl, I): Nitridophosphate Halides with Zeolite-like Structure (Chem. Mater, 2015, 27, 6432-6441) and Pucher et al. ( Luminescent Nitridophosphates CaP 2 N 4 Eu 2+ , SrP 2 N 4 Eu 2+ BaP 2 N 4 Eu 2+ , and BaSr 2 P 6 N 12 Eu 2+ (Chem. Eur. J., 2015, 21, 6443-6448) describes the small-scale acquisition of luminescent hypophosphite in a multi-anvil apparatus under pressures in the GPa range. Attached Figure Description

[0008] Figure 1 A method for commercially manufacturing hypophosphite comprising hypophosphite phosphors is shown.

[0009] Figure 2 The image is a scanning electron microscope (“SEM”) image of Ca2PN3:Eu obtained from Example 2.

[0010] Figure 3The powder X-ray diffraction (“PXRD”) pattern (Cu Kα radiation) of the isolated Ca2PN3:Eu powder obtained from Example 2 is shown.

[0011] Figure 4 This is a schematic diagram of the crystal structure of Ca2PN3.

[0012] Figure 5 The normalized excitation and emission spectra of the obtained Ca2PN3:Eu are shown.

[0013] Figure 6 Sr3P5N obtained from Example 4 10 Scanning electron microscope image of Cl:Eu.

[0014] Figure 7 The isolated Sr3P5N obtained from Example 4 is shown. 10 Powder X-ray diffraction pattern of Cl:Eu powder (Cu Kα radiation).

[0015] Figure 8 It is Sr3P5N 10 A schematic diagram of the crystal structure of Cl:Eu.

[0016] Figure 9 The obtained Sr3P5N is shown. 10 Normalized excitation and emission spectra of Cl:Eu.

[0017] Figure 10 Sr3P5N obtained from Example 6 10 Scanning electron microscope image of Br:Eu.

[0018] Figure 11 The isolated Sr3P5N obtained from Example 6 is shown. 10 Powder X-ray diffraction pattern of Br:Eu powder (Cu Kα radiation).

[0019] Figure 12 The obtained Sr3P5N is shown. 10 Normalized excitation and emission spectra of Br:Eu.

[0020] Figure 13 Ba3P5N obtained from Example 8 10 Scanning electron microscope image of Cl:Eu.

[0021] Figure 14 The isolated Ba3P5N obtained from Example 8 is shown. 10 Powder X-ray diffraction pattern of Cl:Eu powder (Cu Kα radiation).

[0022] Figure 15 The obtained Ba3P5N is shown.10 Normalized excitation and emission spectra of Cl:Eu.

[0023] Figure 16 Ba3P5N obtained from Example 10 10 Scanning electron microscope image of Br:Eu.

[0024] Figure 17 The isolated Ba3P5N obtained from Example 10 is shown. 10 Powder X-ray diffraction pattern of Br:Eu powder (CuKα radiation).

[0025] Figure 18 The obtained Ba3P5N is shown. 10 Normalized excitation and emission spectra of Br:Eu.

[0026] Figure 19 A wavelength conversion structure comprising at least one disclosed hyponitrophosphate phosphor material is shown. Detailed Implementation

[0027] This specification discloses an industrial manufacturing method for producing hyponitrophosphates (including hyponitrophosphate phosphors), and a novel hyponitrophosphate phosphor for use in pcLEDs.

[0028] As used herein, the term "hypophosphite" refers to a crystalline substance having PN bonds and tetrahedral structural units, wherein phosphorus is the central atom and at least one nitrogen atom is located at a vertex of the tetrahedron. Hypophosphites include, for example, M... a P b N x O y X z Where M is a metal or combination of metals, such as rare earth or alkali metals, and X is a halide. For example, hypophosphite includes M. a P b N x O y X z Where M = Ca, Sr, Ba, Eu, Ce, La, Y and / or Lu; and X = F, Cl, Br or I; a > 0, b > 0, x > 0, y ≥ 0, and z ≥ 0. Specific hypophosphite includes, for example, SrP3N5O, Ba6P 12 N 17 O9Br, MP2N4 (M = Sr, Ba) and Ba3P5N 10 X (X = Cr, Br, I).

[0029] This hyponitrophosphate can be used as the host lattice material for solid-state lighting phosphors. As used herein, the term "hyponitrophosphate phosphor" refers to a hyponitrophosphate as defined above and includes dopants that cause the resulting material to emit light. In hyponitrophosphate phosphors, the P(N,O)4 tetrahedral structural units in the host lattice structure can be further connected to other tetrahedral structural units by means of vertex, edge, or face sharing. Hyponitrophosphate phosphors include, for example, M... a P b A q N r O y X z :D, where D is the dopant, M and X are as defined above, A = A1 and / or Si, and a > 0, b > 0, r > 0, q ≥ 0, y ≥ 0, and z ≥ 0. The dopant D can include, for example, Eu. 2+ and Ce 3+ Examples of novel hyponitrophosphate phosphors include, for example, Ca2PN3:Eu and Sr3P5N. 10 X:Eu (where X = Cl, Br), and examples also include MLi3PO2N2:Eu, MLiMg2PN4:Eu, MLi2AlPN4:Eu, M2Li5P3N8:Eu, MLi2Al3PN6:Eu, MLi2Be2P2N6:Eu, MLi4P2N4:Eu, M2AlPSi3N8:Eu, M3P6O6N8:Eu (M = Ca, Sr, Ba).

[0030] method

[0031] Previously, hypophosphites, including hypophosphite phosphors, could only be synthesized by applying high ammonia pressure, using ammonothermal synthesis conditions, and / or in a multi-anvil press under nitrogen pressure exceeding 1 GPa, where the resulting sample volume was no more than a few centimeters. 3 Using this method, the synthesis of hypophosphite is limited to small-scale operations and is costly, restricting their potential commercial applications. The method disclosed herein allows for the cost-effective, large-scale synthesis of hypophosphite phosphors.

[0032] Figure 1A method 100 for commercially scaled production of hypophosphite comprising a hypophosphite phosphor is shown. In S110, hypophosphite precursor materials are combined to form a precursor mixture. This hypophosphite precursor material may include a metal source material of M, a phosphorus source material of P, and a nitrogen source material of N, and may also include oxygen (when y > 0 in the desired hypophosphite), aluminum and / or silicon source materials (for A, when q > 0 in the desired hypophosphite), and halide source materials (for X, when z > 0 in the desired hypophosphite). When the desired compound is a hypophosphite phosphor, a dopant source material of D is also included in the precursor mixture.

[0033] Metal source materials may include, for example, metal azides, metal nitrides, metal hydrides, and / or metal halides.

[0034] Phosphorus source materials can include, for example, elemental phosphorus (such as red phosphorus), as well as PN4, PON, and / or P3N5. An unexpected result is that the methods disclosed herein can successfully synthesize hyponitrophosphate compounds using elemental (red) phosphorus as a phosphorus precursor source. The use of triphosphine pentanitride P3N5 as a phosphorus precursor source may be limited because the synthesis of P3N5 may be difficult to achieve commercially viable levels.

[0035] Nitrogen source materials can be provided as counterions in conjunction with metal source material compounds, such as with metal azides or metal nitrides, and / or in compounds containing phosphorus source materials, such as with HPN2, HP4N7, PON, and / or P3N5. Nitrogen source materials can also be nitrogen gas.

[0036] When y > 0, oxygen source materials can be provided as part of phosphorus source material compounds and / or nitrogen source material compounds, such as PON and / or phosphates (such as Li3PO4, (NH4)2HPO4, NH4H2PO4, CaHPO4, SrHPO4, BaHPO4).

[0037] When q > 0, aluminum source materials and / or silicon source materials can be provided as, for example, metallic Al, AlN, Al2O3, AlF3, metallic Si, Si(NH)2, Si3N4, SiO2 and / or SiO.

[0038] When z > 0, halide source materials can be provided as halide counterions together with, for example, metal source material compounds (e.g., metal halides), and / or as dopant sources of halides.

[0039] The dopant source material can be, for example, EuCl2, Eu2O3, EuF3, EuCl3, EuF2, CeO2, or CeF3.

[0040] Precursor source materials can be mixed using solid-state methods known to those skilled in the art. For example, powders of precursor source materials can be combined and ground together to form a precursor mixture.

[0041] exist Figure 1 In S120, a mixture of precursor materials is placed in a pressure furnace. Oxygen and any other gases are removed from the pressure furnace by purging with nitrogen. The precursor materials in the gas furnace are heated under nitrogen at a moderate, isostatic pressure. The partial pressure of nitrogen used to form the hyponitrophosphate compound can be in the range of 2-300 MPa. During the reaction, the gas used in the pressurized gas furnace can be 100% nitrogen, but may also include inert gases (such as argon, or the less rare helium). For nitriding reactions, it is sometimes useful to “dilute” the nitrogen with argon to slow down the highly exothermic reaction; in this case, a mixture of nitrogen and inert gases can be used. The total pressure of such a nitrogen and inert gas mixture used in the reaction can be in the range of 2-500 MPa, with a nitrogen partial pressure in the range of 2-300 MPa and an inert gas partial pressure in the range of 10-200 MPa. The temperature of the furnace used to form the hyponitrophosphate compound can be in the range of 800-1300 °C.

[0042] The nitrogen pressure used in hot isostatic pressing (HIP) processes needs to be high enough to prevent the precursor source materials (such as nitrides) from decomposing under heating and to stabilize the materials during synthesis. Traditionally, argon is used in pressure furnaces, but the inventors have discovered that using nitrogen allows for heating of the precursors and allows the precursor materials to form hypophosphite under heat. Higher nitrogen pressures are used at higher temperatures in the furnace to form hypophosphite compounds because the higher nitrogen pressure increases the decomposition temperature of the precursor materials, thus allowing for the use of higher temperatures. Additionally, the decomposition temperature of the formed hypophosphite phosphor is increased.

[0043] The time required to form hypophosphite compounds under thermoisostatic pressure reaction conditions varies depending on the hypophosphite compound synthesized, but can range from 2 to 96 hours.

[0044] Any pressure furnace capable of providing heat and nitrogen at the desired temperature and pressure can be used. For example, commercially available hot isostatic pressing (HIP) furnaces, such as HIP graphite furnaces, can be used to form hyponitrophosphate compounds using the methods disclosed herein.

[0045] The method for synthesizing hyponitrophosphates disclosed herein offers at least two advantages over conventional methods. First, unlike conventional methods for synthesizing hyponitrophosphate compounds, the method disclosed herein allows for the synthesis of large quantities of hyponitrophosphate compounds, enabling their commercial application in applications such as pcLEDs. For example, this method allows for the synthesis of 1 / 2 kg of hyponitrophosphate in a single batch (one run). This makes the synthesis of hyponitrophosphate compounds cost-effective. Second, an unexpected result is that moderate nitrogen pressures can be used for the synthesis of hyponitrophosphates. Conventional methods for synthesizing hyponitrophosphates typically use nitrogen pressures exceeding 1 GPa in multi-anvil presses. The pressure range of MPa used in the method disclosed herein is typically three orders of magnitude lower than the pressures conventionally used to form hyponitrophosphates. Therefore, the pressures used in this method are significantly less than 1 GPa and can be less than 300 MPa, for example less than 150 MPa, and as low as 20 MPa.

[0046] For example, in S130, after the furnace is restored to room temperature and atmospheric pressure, the synthesized hyponitrophosphate can be removed from the furnace. The synthesized hyponitrophosphate is a crystalline material. As described below, the synthesized hyponitrophosphate phosphor can be used to form pcLEDs.

[0047] Example reaction

[0048] Using a given pressure range (MPa), maximum temperature (°C), and residence time in the furnace (h = hours) ("x" indicates stoichiometry in (a) and (b)), a novel phosphor, Ca2PN3:Eu, can be synthesized by any of the following three reactions ((a)-(c)).

[0049] .

[0050] As another example, using a given pressure range (MPa), maximum temperature (°C), and residence time in the furnace (h = hours) ("x" indicates stoichiometry in (d) and (e)), the novel phosphor M3P5N can be synthesized by either of the following two reactions ((d)-(e)). 10 X:Eu (M = Sr, Ba; X = Cl, Br):

[0051] .

[0052] Non-commercial precursors such as P3N5 or M(N3)2 used in the reactions listed above can be synthesized according to literature methods (see, for example, supporting information from Marchuk and Schnick). Ba 3 P 5N 10 Br:Eu 2+ :A Natural-White-Light Single Emitter with a Zeolite Structure Type (Angew. Chem. Int. Ed., 2015, 54, 2383–2387), and a more detailed description is provided in the specific examples below.

[0053] Although the examples provided in this article use Eu 2+ As a dopant, but if for a given host lattice Eu 2+ Since luminescence is known, then Ce 3+ Emission is also known. This is because the Stokes shift is a property of the principal lattice. Therefore, if Eu 2+ Phosphors emit in the red (green) spectral range, therefore Ce in the same host... 3+ Phosphors emit light in the green-yellow (blue) spectral range.

[0054] Example

[0055] Example 1: Synthesis of Ca2PN3:Eu(3%) using P3N5 source material

[0056] To form Ca2PN3:Eu, 32.3 mg (0.22 mmol) of Ca3N2 (>99%, Taiheiyo Cement), 17.73 mg (0.11 mmol) of P3N5 (synthesized below), and 1.47 mg (>0.01 mmol) of EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1200 °C under a N2 atmosphere for 20 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ca2PN3:Eu (3%) was obtained.

[0057] The synthesis of P3N5 source material is as follows: P4S 10 (Approximately 8.0 g, Sigma-Aldrich 99.99%) was treated in a drying tube furnace lined with a quartz tube (Ø = 5 cm) by a constant flow of dry NH3 (≈ 3.6 l / h, Air Liquide 5.0). Initially, the apparatus was purged with NH3 for 4 h, and then heated to 850 °C over 3 h. This temperature was maintained for 4 h, and then cooled back to room temperature over 3 h. Residual NH3 was removed by rinsing with Ar for 1 h.

[0058] Example 2: Synthesis of Ca2PN3:Eu(3%) using elemental phosphorus source material

[0059] To form Ca2PN3:Eu, 64.8 mg (0.52 mmol) of Ca(N3)2 (synthesized as described below) and 8.1 mg (0.26 mmol) of P were used. red (≥ 99.999%, ChemPur) and 3.45 mg (0.02 mmol) of EuCl2 (99.9%, StremChemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1200 °C for 20 h under N2 atmosphere. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ca2PN3:Eu (3%) was obtained.

[0060] To form Ca(N3)2, the following method for synthesizing azides of Ca, Sr, and Br was used: Alkaline earth metal azides M(N3)2 (M = Ca, Sr, Ba) were synthesized via a cation exchanger (Amberlyst 15). Diluted HN3 was formed in situ by passing an aqueous solution of NaN3 (AcrosOrganics, 99%, ultrapure) through a cation exchanger. The acidic solution of HN3 was carefully added dropwise to a suspension of MCO3 (M = Ca, Sr, Ba) in stirred H2O. In the case of Ca(N3)2, CaCO3 (Merck, analytical grade) was used. The reaction was considered complete when the liquid phase indicated the end of the reaction. Excess alkaline earth carbonates were filtered off, and the filtrate was restricted using a rotary evaporator (50 mbar, 40 °C). The resulting azide was a colorless powder and was purified by recrystallization from acetone.

[0061] Figure 2 The image is a scanning electron microscope (“SEM”) image of Ca2PN3:Eu obtained from Example 2. Figure 2 Rod-shaped particles were shown, and the obtained Ca2PN3:Eu could be ground into powder form.

[0062] Figure 3 The powder X-ray diffraction (PXRD) pattern (Cu Kα radiation) of the isolated Ca2PN3:Eu powder is shown. Ca2PN3 crystallizes in orthorhombic space group Cmca (number 64) with cell parameters a = 5.1908 Å, b = 10.3132 Å, and c = 11.2845 Å. Rietveld refinement of the obtained Ca2PN3:Eu luminescent material is also shown. Figure 3 The image shows the reflection position (301) of the obtained Ca2PN3:Eu.

[0063] Table 1 summarizes the atomic parameters of the obtained Ca2PN3:Eu structures. In Table 1, an “atom” is a substance occupying a lattice position with a specific Wyckoff position (“Wyck”). The headings “x / a”, “y / b”, and “z / c” in Table 1 refer to the coordinates of the atomic positions in the lattice, defined by the lattice constants a, b, and c. In orthorhombic lattice systems, a ≠ b ≠ c, and α = β = γ = 120°.

[0064]

[0065] Figure 4 This is a schematic diagram of the Ca2PN3 crystal structure, as shown below. Figure 4 As shown, it consists of an infinite zweier single chain of PN4 tetrahedra sharing vertices.

[0066] The obtained energy dispersive X-ray spectroscopy (“EDS”) scan of Ca2PN3:Eu showed that the ratio of Ca:P:N was 1.80:1:3.36.

[0067] Figure 5 The normalized excitation spectrum 501 and emission spectrum 502 of the obtained Ca2PN3:Eu are shown.

[0068] Example 3: Synthesis of Sr3P5N using P3N5 source material 10 Cl:Eu(3%)

[0069] In order to form Sr3P5N 10 Cl:Eu, 43.40 mg (0.25 mmol) Sr(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is SrCO3 (99.995%, Sigma-Aldrich)), 8.02 mg (0.05 mmol) SrCl2 (>99.99%, Sigma-Aldrich), 27.47 mg (0.17 mmol) P3N5 (synthesized as described above with respect to Example 1), and 1.67 mg (~0.1 mmol) EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1000 °C under a N2 atmosphere for 10 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Sr3P5N was obtained. 10 Cl:Eu(3%).

[0070] Example 4: Synthesis of Sr3P5N using elemental phosphorus source materials 10 Cl:Eu(3%)

[0071] In order to form Sr3P5N 10Cl:Eu, 60.0 mg (0.35 mmol) Sr(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is SrCO3 (99.995%, Sigma-Aldrich)), 11.08 mg (0.07 mmol) SrCl2 (> 99.99%, Sigma-Aldrich), 21.66 mg (0.70 mmol) P red (≥ 99.999%, ChemPur) and 2.34 mg (0.01 mmol) of EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1100 °C under a N2 atmosphere for 20 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Sr3P5N was obtained. 10 Cl:Eu(3%).

[0072] Figure 6 Sr3P5N obtained from Example 4 10 Scanning electron microscope image of Cl:Eu (strip length, 5 μm). Figure 6 The obtained Sr3P5N is shown. 10 Cl:Eu in block form can be ground into powder.

[0073] Figure 7 The isolated Sr3P5N is shown. 10 Powder X-ray diffraction pattern of Cl:Eu powder (Cu Kα radiation). Sr3P5N 10 Cl crystallizes in orthorhombic space group Pnma (number 62) with cell parameters a = 12.2410 Å, b = 12.9530 Å and c = 13.4270 Å. The obtained Sr3P5N... 10 Rietveld refinement of Cl:Eu luminescent material is also in progress Figure 7 The diagram shows the obtained Sr3P5N 10 The reflection position of Cl:Eu is (701).

[0074] Table 2 summarizes the obtained Sr3P5N. 10 Atomic parameters of the Cl:Eu structure. In Table 2, “atom” refers to a substance occupying a lattice position with a specific Wyckoff position (“Wyck”). The heading “SOF” refers to the site occupancy factor of the split position. The headings “x / a”, “y / b”, and “z / c” in Table 2 refer to the coordinates of the atomic positions in the lattice, defined by the lattice constants a, b, and c. In orthorhombic lattice systems, a ≠ b ≠ c, and α = β = γ = 120°.

[0075]

[0076] Obtained Sr3P5N 10 Energy-dispersive X-ray spectroscopy of Cl:Eu showed that the ratio of Sr:P:N:Cl was 2.55:4.64:9.81:1.

[0077] Figure 8 It is Sr3P5N 10 A schematic diagram of the crystal structure of Cl:Eu is shown below. Figure 8 As shown, it consists of PN4 tetrahedra shared by all edge vertices. The framework topology is similar to that of JOZ zeolites. This structural type exhibits heterocyclic channels alternately filled with Sr and Cl ions.

[0078] Figure 9 The obtained Sr3P5N is shown. 10 Normalized excitation spectrum 901 and emission spectrum 902 of Cl:Eu.

[0079] Example 5: Synthesis of Sr3P5N using P3N5 source material 10 Br:Eu

[0080] In order to form Sr3P5N 10 Br:Eu, 40.38 mg (0.24 mmol) Sr(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is SrCO3 (99.995%, Sigma-Aldrich)), 11.64 mg (0.05 mmol) SrBr2 (99.995%, Sigma-Aldrich), 25.55 mg (0.16 mmol) P3N5 (synthesized as described above with respect to Example 1), and 1.57 mg (>0.01 mmol) EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1000 °C under a N2 atmosphere for 10 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Sr3P5N was obtained. 10 Br:Eu.

[0081] Example 6: Synthesis of Sr3P5N using elemental phosphorus source materials 10 Br:Eu

[0082] In order to form Sr3P5N 10 Br:Eu, 60.0 mg (0.35 mmol) Sr(N3)2 (synthesized as disclosed above with respect to Example 2, wherein MCO3 is SrCO3 (99.995%, Sigma-Aldrich)), 17.30 mg (0.07 mmol) SrBr2 (99.995%, Sigma-Aldrich), 21.65 mg (0.70 mmol) P redSr3P5N (≥99.999%, ChemPur) and 2.34 mg (>0.01 mmol) of EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1100 °C under a N2 atmosphere for 20 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Sr3P5N was obtained. 10 Br:Eu.

[0083] Figure 10 Sr3P5N obtained from Example 6 10 Scanning electron microscope image of Br:Eu (strip length, 5 μm). Figure 10 The obtained Sr3P5N is shown. 10 Br:Eu in block form can be ground into powder.

[0084] Figure 11 The isolated Sr3P5N is shown. 10 Powder X-ray diffraction pattern of Br:Eu powder (Cu Kα radiation). Sr3P5N 10 Br crystallizes in orthorhombic space group Pnma (number 62) with cell parameters a = 12.2970 Å, b = 12.9896 Å and c = 13.4585 Å. The obtained Sr3P5N... 10 Rietveld refinement of Br:Eu luminescent material is also underway. Figure 11 The diagram shows the obtained Sr3P5N 10 The reflection position of Br:Eu is (1101).

[0085] Table 3 summarizes the obtained Sr3P5N. 10 Atomic parameters of the Br:Eu structure. In Table 3, “atom” refers to a substance occupying a lattice position with a specific Wyckoff position (“Wyck”). The heading “SOF” refers to the site occupancy factor of the split position. The headings “x / a”, “y / b”, and “z / c” in Table 3 refer to the coordinates of the atomic positions in the lattice, defined by the lattice constants a, b, and c. In orthorhombic lattice systems, a ≠ b ≠ c, and α = β = γ = 120°.

[0086]

[0087] Obtained Sr3P5N 10 Energy-dispersive X-ray spectroscopy of Br:Eu showed a Sr:P:N:Br ratio of 2.72:4.66:7.01:1.

[0088] Figure 12 The obtained Sr3P5N is shown. 10Normalized excitation spectrum 1201 and emission spectrum 1202 of Br:Eu.

[0089] Example 7: Synthesis of Ba3P5N using P3N5 source material 10 Cl:Eu

[0090] In order to form Ba3P5N 10 Cl:Eu, 44.73 mg (0.20 mmol) Ba(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is BaCO3 (99.8%, Grüssing)), 8.41 mg (0.04 mmol) BaCl2 (99.999%, Sigma-Aldrich), 21.95 mg (0.13 mmol) P3N5 (synthesized as described above with respect to Example 1), and 1.35 mg (> 0.01 mmol) EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1000 °C under a N2 atmosphere for 10 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ba3P5N was obtained. 10 Cl:Eu.

[0091] Example 8: Synthesis of Ba3P5N using elemental phosphorus source materials 10 Cl:Eu

[0092] In order to form Ba3P5N 10 Cl:Eu, 35.00 mg (0.16 mmol) Ba(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is BaCO3 (99.8%, Grüssing)), 6.58 mg (0.03 mmol) BaCl2 (99.999%, Sigma-Aldrich), 9.79 mg (0.32 mmol) P red Ba3P5N (≥ 99.999%, ChemPur) and 1.06 mg (> 0.01 mmol) of EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1100 °C under a N2 atmosphere for 20 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ba3P5N was obtained. 10 Cl:Eu.

[0093] Figure 13 Ba3P5N obtained from Example 8 10 Scanning electron microscope image of Cl:Eu (strip length, 5 μm). Figure 13 The obtained Ba3P5N is shown. 10 Cl:Eu in block form can be ground into powder.

[0094] Figure 14 The isolated Ba3P5N is shown.10 Powder X-ray diffraction pattern of Cl:Eu powder (Cu Kα radiation). Ba3P5N 10 Cl crystallized in the orthorhombic space group Pnma (number 62) with cell parameters a = 12.5458 Å, b = 13.2142 Å and c = 13.7857 Å. The obtained Ba3P5N... 10 Rietveld refinement of Cl:Eu luminescent material is also in progress Figure 14 The diagram shows the obtained Ba3P5N 10 The reflection position of Cl:Eu is (1401).

[0095] Table 4 summarizes the obtained Ba3P5N. 10 Atomic parameters of the Cl:Eu structure. In Table 4, “atom” refers to a substance occupying a lattice position with a specific Wyckoff position (“Wyck”). The heading “SOF” refers to the site occupancy factor of the split position. The headings “x / a”, “y / b”, and “z / c” in Table 4 refer to the coordinates of the atomic positions in the lattice, defined by the lattice constants a, b, and c. In orthorhombic lattice systems, a ≠ b ≠ c, and α = β = γ = 120°.

[0096]

[0097] Ba3P5N obtained 10 Energy-dispersive X-ray spectroscopy of Cl:Eu showed that the ratio of Ba:P:N:Cl was 2.83:4.81:8.43:1.

[0098] Figure 15 The obtained Ba3P5N is shown. 10 Normalized excitation spectrum 1501 and emission spectrum 1502 of Cl:Eu.

[0099] Example 9: Synthesis of Ba3P5N using P3N5 source material 10 Br:Eu

[0100] In order to form Ba3P5N 10Br:Eu, 42.20 mg (0.19 mmol) Ba(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is BaCO3 (99.8%, Grüssing)), 11.33 mg (0.04 mmol) BaBr2 (99.999%, Sigma-Aldrich), 20.71 mg (0.13 mmol) P3N5 (synthesized as described above with respect to Example 1), and 1.27 mg (> 0.01 mmol) EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1000 °C under a N2 atmosphere for 10 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ba3P5N was obtained. 10 Br:Eu.

[0101] Example 10: Synthesis of Ba3P5N using elemental phosphorus source materials 10 Br:Eu

[0102] In order to form Ba3P5N 10 Br:Eu, 35.00 mg (0.16 mmol) Ba(N3)2 (synthesized as described above with respect to Example 2, wherein MCO3 is BaCO3 (99.8%, Grüssing)), 9.40 mg (0.03 mmol) BaBr2 (99.999%, Sigma-Aldrich), 9.79 mg (0.32 mmol) P red Ba3P5N (≥99.999%, ChemPur) and 1.06 mg (>0.01 mmol) of EuCl2 (99.9%, Strem Chemicals) were mixed and sintered in a thermal isostatic pressure furnace at 1500 bar and 1100 °C under a N2 atmosphere for 20 h. After cooling to room temperature and restoring to atmospheric pressure, crystalline Ba3P5N was obtained. 10 Br:Eu.

[0103] Figure 16 Ba3P5N obtained from Example 10 10 Scanning electron microscope image of Br:Eu (strip length, 5 μm). Figure 16 The obtained Ba3P5N is shown. 10 Br:Eu in block form can be ground into powder.

[0104] Figure 17 The isolated Ba3P5N is shown. 10 Powder X-ray diffraction pattern of Br:Eu powder (Cu Kα radiation). Ba3P5N 10Br crystallizes in orthorhombic space group Pnma (number 62) with cell parameters a = 12.5844 Å, b = 13.2290 Å and c = 13.8106 Å. The obtained Ba3P5N... 10 Rietveld refinement of Br:Eu luminescent material is also underway. Figure 17 The diagram shows the obtained Ba3P5N 10 The reflection position of Br:Eu (1701).

[0105] Table 5 summarizes the obtained Ba3P5N. 10 Atomic parameters of the Br:Eu structure. In Table 5, “atom” refers to a substance occupying a lattice position with a specific Wyckoff position (“Wyck”). The heading “SOF” refers to the site occupancy factor of the partitioned position. The headings “x / a”, “y / b”, and “z / c” in Table 5 refer to the coordinates of the atomic positions in the lattice, defined by the lattice constants a, b, and c. In orthorhombic lattice systems, a ≠ b ≠ c, and α = β = γ = 120°.

[0106]

[0107] Ba3P5N obtained 10 Energy-dispersive X-ray spectroscopy of Br:Eu showed that the ratio of Ba:P:N:Br was 3.05:4.97:8.20:1.

[0108] Figure 18 The obtained Ba3P5N is shown. 10 Normalized excitation spectrum 1801 and emission spectrum 1802 of Br:Eu.

[0109] Lighting devices including hyponitrophosphate phosphors

[0110] Figure 19 A wavelength conversion structure 1908 is shown, comprising at least one disclosed hyponitrophosphate phosphor material. The wavelength conversion structure 1908 is used in an illumination device 1901. The light source 1900 can be an LED or any other suitable light source, including, for example, a resonant cavity light-emitting diode (RCLED) and a vertical cavity laser diode (VCSEL). The light source 1900 emits first light 1904. A portion of the first light 1904 is incident on the wavelength conversion structure 1908. The wavelength conversion structure 1908 absorbs the first light 1904 and emits second light 1912. The wavelength conversion structure 1908 can be configured such that little or no of the first light is part of the final emission spectrum from the device, although this is not required.

[0111] Reference Figure 19The wavelength conversion structure 1908 described can be made, for example, in powder form, ceramic form, or any other suitable form. The wavelength conversion structure 1908 can be formed as one or more structures formed separately from and processed separately from the light source (such as precast glass or ceramic tiles), or it can be formed as a structure formed in situ with the light source (such as a conformal coating or other coating formed on or above the light source).

[0112] For example, the wavelength conversion structure 1908 can be, for example, hyponitrophosphate phosphor powder dispersed in a transparent material, such as a silicone material, a glass matrix, a ceramic matrix, or any other suitable material or structure. The hyponitrophosphate phosphor dispersed in the transparent material can be formed directly on the light source, or for example, it can be formed as a matrix, which can be singulated or formed as tiles, which are then placed on the light source.

Claims

1. A method containing M a P b N x X z :D is a luminescent material where M = Ca or Sr, X = F, Cl, Br or I; D = Eu 2+ or Ce 3+ Given that a > 0, b > 0, x > 0, and z ≥ 0, Where M = Ca, a = 2, b = 1, x = 3, and z = 0, or Where M=Sr, a=3, b=5, x=10, and z=1.

2. A wavelength conversion structure comprising the luminescent material according to claim 1.

3. The wavelength conversion structure according to claim 2 further includes a light source that emits first light, the wavelength conversion structure being disposed in the path of the first light, wherein the light-emitting phosphor absorbs the first light and emits second light with a wavelength different from the first light.

4. A method for forming a luminescent hypoazine phosphate, wherein the luminescent hypoazine phosphate comprises M a P b N x X z :D, where M = Ca or Sr, X = F, Cl, Br or I; D = Eu 2+ or Ce 3+ The method comprises: a > 0, b > 0, x > 0, and z ≥ 0, where M = Ca, a = 2, b = 1, x = 3, and z = 0, or M = Sr, a = 3, b = 5, x = 10, and z = 1. A precursor mixture is formed by combining metal source materials, phosphorus source materials, nitrogen source materials, and dopant source materials; and The precursor mixture is heated in a nitrogen-containing atmosphere at a pressure between 2 MPa and 500 MPa, at a maximum temperature between 800°C and 1300°C.

5. The method according to claim 4, wherein the metal source material comprises at least one of metal azides, metal nitrides, metal hydrides and metal halides, and the phosphorus source material comprises at least one of elemental phosphorus, HPN2, HP4N7, PON and / or P3N5.

6. The method of claim 4, wherein the precursor mixture further comprises at least one of an oxygen source material and a halide source material.

7. The method of claim 4, wherein the dopant source material comprises EuCl2.

8. The method according to claim 4, wherein the metal in the metal source material includes at least one of Ca, Sr, Ba, Eu, Ce, La, Y and Lu.

9. The method of claim 4, wherein the highest temperature is between 1000°C and 1200°C.

10. The method of claim 4, wherein the atmosphere is composed of nitrogen.

11. The method of claim 4, wherein the atmosphere comprises a mixture of nitrogen gas with a partial pressure between 2 MPa and 300 MPa and argon gas with a partial pressure between 10 MPa and 200 MPa.

12. The method of claim 4, wherein the precursor mixture comprises at least one of Ca3N2 and Ca(N3)2, P3N5 and P red At least one of them, and EuCl2.

13. The method of claim 4, wherein the precursor mixture comprises M(N3)2, P3N5, and P red At least one of them, MX2, and EuCl2 (M=Sr, Ba, X=Cl, Br).

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