Yellow fluorescent powder for white-light LED, preparation method and white-light LED device

Abstract

The invention relates to the technical field of white-light LEDs, in particular to yellow fluorescent powder for white-light LEDs, a preparation method and a white-light LED device, raw materials of all elements are weighed according to the chemical formula in proportion, and after weighing, the raw materials are directly dissolved in solvent acetone, N, N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile to be stirred or subjected to ultrasonic reaction. And directly filtering the mixed solution added with the raw materials to obtain a powder particle crude product. And cleaning the crude product with acetone, N, N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile, drying, crushing and sieving to obtain the yellow fluorescent powder. The simplest and direct aqueous solution synthesis method is adopted, the operation is simple and convenient, the reaction temperature is low, the reaction is rapid, additional energy consumption is not needed, the repeatability is high, the defects of high temperature, high pressure and the like of traditional fluorescent powder preparation are avoided, and white light can be emitted without adding other fluorescent powder; the raw materials are rich in source, low in production cost, high in commercial use value and beneficial to long-term development.

Description

Technical Field

[0001] The invention relates to the technical field of white light LEDs, and in particular to a yellow fluorescent powder for white light LEDs, a preparation method and a white light LED device. Background Art

[0002] White LEDs can be obtained by coating blue LED chips with highly efficient phosphors that can be effectively stimulated by blue light and emit yellow light. The successful research of white LED light sources has created conditions for the application of LEDs in general lighting. White LEDs are also known as the fourth generation of green lighting sources and are widely used in daily lighting, room temperature supplementary lighting, traffic lights and other fields.

[0003] Currently, most commercial phosphors are usually inorganic phosphors doped with rare earth elements (REE), including oxides, sulfides, phosphor oxides, and nitrogen oxides. However, this type of phosphor is too dependent on rare earth elements, which brings certain supply and price risks. In addition, the high energy consumption of rare earth phosphor synthesis is not conducive to long-term development.

[0004] To address these issues, there is an urgent need to find new environmentally friendly, resource-abundant phosphors that do not contain rare earth elements to improve the performance of commercial LEDs. Summary of the invention

[0005] The purpose of the present invention is to provide a yellow phosphor for white light LED, a preparation method and a white light LED device, which solves the problems that existing commercial phosphors are usually inorganic compounds doped with rare earth elements, which have supply and price risks, and the high energy consumption synthesis of rare earth phosphors is not conducive to long-term development.

[0006] To achieve the above object, the present invention provides a method for preparing yellow phosphor for white light LED, comprising the following steps:

[0007] Weigh the corresponding element compound raw materials according to the chemical formula, and dissolve the raw materials in a solvent to react;

[0008] The mixed solution after the reaction is filtered to obtain a crude powder particle product;

[0009] The crude product is treated with a solvent to obtain yellow phosphor.

[0010] Wherein, the corresponding element compound raw materials are weighed according to the chemical formula, and after weighing, the raw materials are dissolved in a solvent for reaction, and the step further includes:

[0011] The chemical formula is Ma(18-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6.

[0012] Wherein, the corresponding element compound raw materials are weighed according to the chemical formula, and after weighing, the raw materials are dissolved in a solvent for reaction, and the step further includes:

[0013] The raw materials used are BaI2, CaI2, SrI2, MgI2, CuI, C 12 H 24 O618-crown-6), H3PO2.

[0014] Wherein, the corresponding element compound raw materials are weighed according to the chemical formula, and the raw materials are dissolved in a solvent to react after weighing, and the step further includes:

[0015] The solvent is acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile.

[0016] Wherein, the crude product is treated with a solvent to obtain yellow phosphor, and the step further comprises:

[0017] The crude product is washed with acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile, dried, crushed and sieved to obtain yellow fluorescent powder.

[0018] A yellow phosphor for a white light LED has a structural formula of Ma(8-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6.

[0019] A white light LED device comprises a blue light emitting chip and yellow phosphor arranged on the blue light emitting chip.

[0020] The yellow fluorescent powder is mixed with UV glue or PDMS colloid and then packaged on the blue light emitting chip.

[0021] The present invention discloses a yellow phosphor for white light LED, a preparation method and a white light LED device. The raw materials of each element are weighed in proportion according to the chemical formula Ma(18-crown-6)bCucId·Xe·fH2O, and are directly dissolved in a solvent such as acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile for stirring or ultrasonic reaction. The mixed solution after adding the raw materials is directly filtered to obtain a crude powder particle product. The crude product is washed with acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile, dried, crushed and sieved to obtain a yellow phosphor. The raw materials used in the above method are BaI2, CaI2, SrI2, MgI2, CuI, C 12 H 24 O618-crown-6), H3PO2. A white light LED device comprises the blue light emitting chip and the yellow phosphor arranged on the blue light emitting chip, wherein the yellow phosphor can be directly placed on the blue light emitting chip, and can also be mixed with UV glue or PDMS and other colloids and then packaged on the blue light emitting chip, and a white light LED device with stable light emission and not easy to be damaged can be obtained after packaging, and the simplest and most direct aqueous solution synthesis method is adopted, which is easy to operate, has a low reaction temperature, a rapid reaction, does not require additional energy consumption, has strong repeatability, and avoids the disadvantages of high temperature and high pressure in the preparation of traditional phosphors, and can obtain a yellow phosphor for white LED with blue light excitation having a wide excitation range (250-500nm) and a wide emission range (450-800nm) by replacing or adjusting the element ratio, i.e., the yellow phosphor, which can emit white light without adding other phosphors; the raw material source is abundant, the production cost is low, the commercial use value is high, and it is conducive to long-term development. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0023] Figure 1 This is the XRD diagram of the Ba(18-crown-6)2Cu4I6·H3PO2·H2O phosphor of the present invention.

[0024] Figure 2 It is the emission spectrum diagram of Ba(18-crown-6)2Cu4I6·H3PO2·H2O of the present invention at 450nm excitation and the excitation spectrum diagram monitored at 538nm.

[0025] Figure 3 It is the fluorescent pink coordinates (x=0.39, y=0.55) of the Ba(18-crown-6)2Cu4I6·H3PO2·H2O of the present invention.

[0026] Figure 4 This is a light emission spectrum diagram of a white light LED device based on Ba(18-crown-6)2Cu4I6·H3PO2·H2O phosphor of the present invention.

[0027] Figure 5 This is the XRD diagram of the Ca(18-crown-6)Cu5I7·3H2O phosphor of the present invention.

[0028] Figure 6 The emission spectrum of Ca(18-crown-6)Cu5I7·3H2O4 of the present invention is excited at 22nm and monitored at 528nm.

[0029] Figure 7 The fluorescent pink coordinates of the Ca(18-crown-6)Cu5I7·3H2O of the present invention are (x=0.36, y=0.54).

[0030] Figure 8 This is a light emission spectrum diagram of a white light LED device of the Ca(18-crown-6)Cu5I7·3H2O phosphor of the present invention.

[0031] Fig. 9 The present invention is a flowchart of the steps of the method for preparing yellow phosphor for white light LED.

[0032] Fig.10 It is a schematic structural diagram of the white light LED device of the present invention.

[0033] In the figure: 301- blue light-emitting chip, 302- yellow phosphor. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0035] The first embodiment of the present application is:

[0036] See also Figures 1 to 9 ,in, Figure 1 This is the XRD diagram of the Ba(18-crown-6)2Cu4I6·H3PO2·H2O phosphor of the present invention. Figure 2 It is the emission spectrum diagram of Ba(18-crown-6)2Cu4I6·H3PO2·H2O of the present invention under 450nm excitation and the excitation spectrum diagram monitored under 538nm. Figure 3 It is the fluorescent pink coordinates (x=0.39, y=0.55) of the Ba(18-crown-6)2Cu4I6·H3PO2·H2O of the present invention. Figure 4This is a light emission spectrum diagram of a white light LED device based on Ba(18-crown-6)2Cu4I6·H3PO2·H2O phosphor of the present invention. Figure 5 This is the XRD diagram of the Ca(18-crown-6)Cu5I7·3H2O phosphor of the present invention. Figure 6 The emission spectrum of Ca(18-crown-6)Cu5I7·3H2O of the present invention is excited at 422nm and monitored at 528nm. Figure 7 The fluorescent pink coordinates of the Ca(18-crown-6)Cu5I7·3H2O of the present invention are (x=0.36, y=0.54). Figure 8 This is a light emission spectrum diagram of a white light LED device of the Ca(18-crown-6)Cu5I7·3H2O phosphor of the present invention. Fig. 9 The present invention provides a method for preparing yellow phosphor 302 for white light LED, which comprises the following steps:

[0037] S101: Weigh corresponding element compound raw materials according to chemical formula, and dissolve the raw materials in a solvent to react;

[0038] S102: filtering the mixed solution after the reaction to obtain a crude powder particle product;

[0039] S103: The crude product is treated with a solvent to obtain yellow phosphor 302.

[0040] Specifically, the raw materials of each element are weighed in proportion according to the chemical formula Ma(18-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6. After weighing, the raw materials are directly dissolved in a solvent such as acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol, or acetonitrile for stirring or ultrasonic reaction. The mixed solution after adding the raw materials is directly filtered to obtain a crude powder particle product. The crude product is washed, dried, crushed, and sieved with acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol, or acetonitrile to obtain a yellow phosphor 302. The raw materials used are BaI2, CaI2, SrI2, MgI2, CuI, C 12 H 24 O6(18-crown-6),H3PO2.

[0041] It adopts the simplest and most direct aqueous solution synthesis method, which is easy to operate, has a low reaction temperature, a rapid reaction, does not require any external energy, has strong repeatability, avoids the shortcomings of traditional phosphor preparation such as high temperature and high pressure, and can emit white light without adding other phosphors. It has abundant raw material sources, low production costs, high commercial use value, and is conducive to long-term development.

[0042] Specific embodiment 1, the present invention provides a blue light excited yellow phosphor 302, whose chemical formula is Ba(18-crown-6)2Cu4I6·H3PO2·H2O. It can be seen from the XRD diffraction spectrum that it has a monoclinic P21 / c structure.

[0043] The present invention also provides a method for preparing the blue light excited yellow phosphor, comprising the following steps:

[0044] Step 1, weigh the corresponding element compound raw materials, barium iodide, cuprous iodide, 18-crown-6, and H3PO2 according to the chemical formula, and place them in a reaction vessel such as a reaction vessel beaker or a reaction kettle.

[0045] Step 2: Add a reaction solvent such as acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile to a reaction vessel containing raw materials, stir or perform ultrasonic reaction, and obtain a mixed solution after the reaction is completed.

[0046] Step 3, filtering the mixed solution to obtain a yellow powder solid.

[0047] Step 4: Wash, dry, grind and sieve the powder solid product to obtain the blue light excited yellow phosphor 302.

[0048] Specific embodiment 2, the present invention provides a blue light excited yellow phosphor 302, whose chemical formula is Ca(18-crown-6)Cu5I7·3H2O. It can be seen from the XRD diffraction spectrum that it has a Pbcm space group.

[0049] The present invention also provides a method for preparing the blue light excited yellow phosphor, comprising the following steps:

[0050] Step 1, weigh the corresponding element compound raw materials according to the chemical formula, calcium iodide, cuprous iodide, and 18-crown-6 and place them in a reaction vessel such as a reaction vessel beaker or a reaction kettle.

[0051] Step 2: Add a reaction solvent such as acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile to a reaction vessel containing raw materials, stir or perform ultrasonic reaction, and obtain a mixed solution after the reaction is completed.

[0052] Step 3, filtering the mixed solution to obtain a yellow powder solid.

[0053] Step 4: Wash, dry, grind and sieve the powder solid product to obtain the blue light excited yellow phosphor 302.

[0054] The second embodiment of the present application is:

[0055] On the basis of the first embodiment, a yellow phosphor 302 for white light LED of this embodiment has a structural formula of Ma(18-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6.

[0056] The third embodiment of the present application is:

[0057] Based on the second embodiment, please refer to Fig.10 ,in, Fig.10 The white light LED device of the present invention is a schematic diagram of the structure of the white light LED device. A white light LED device of the present embodiment includes a blue light emitting chip 301 and a yellow phosphor 302 .

[0058] According to this specific implementation, the yellow phosphor is mixed with UV glue or PDMS colloid and then packaged on the blue light emitting chip 301 .

[0059] The yellow phosphor 302 can be directly placed on the blue light-emitting chip 301, and can also be mixed with UV glue or PDMS and other colloids and then packaged on the blue light-emitting chip 301. After packaging, a white light LED device with stable light emission and not easy to be damaged can be obtained. The yellow phosphor 302 is the yellow phosphor 302 excited by blue light of the present invention.

[0060] The blue light LED chip of the present invention can adopt an InGnN semiconductor LED chip with a light emission wavelength of 460nm.

[0061] The present invention has no special limitation on the amount of the yellow phosphor 302, which can be adjusted according to actual needs. The blue light LED chip is a GaN semiconductor chip, such as an InGnN semiconductor LED chip, and its emission peak wavelength is 460nm. The blue light-excited yellow phosphor 302 provided by the present invention has the advantages of wide excitation in the blue light region, high color purity, good thermal stability and chemical stability, and is suitable for blue light chips and blue light-excited assembled LED devices; the white light LED device provided by the present invention makes up for the shortcomings of traditional commercial white light LED devices due to the lack of directly assembled yellow phosphor 302.

[0062] What is disclosed above is only one or more preferred embodiments of the present application, and cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A method for preparing yellow phosphor for white light LED, characterized in that: The following steps are involved: Weigh the corresponding element compound raw materials according to the chemical formula, and dissolve the raw materials in a solvent to react; The mixed solution after the reaction is filtered to obtain a crude powder particle product; The crude product is treated with a solvent to obtain yellow phosphor.

2. The method for preparing yellow phosphor for white light LED according to claim 1, characterized in that: Weigh the corresponding element compound raw materials according to the chemical formula, and then dissolve the raw materials into the solvent for reaction. The steps also include: The chemical formula is Ma(18-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6.

3. The method for preparing yellow phosphor for white light LED according to claim 1, characterized in that: Weigh the corresponding element compound raw materials according to the chemical formula, and then dissolve the raw materials into the solvent for reaction. The steps also include: The raw materials used are BaI2, CaI2, SrI2, MgI2, CuI, C 12 H 24 O6(18-crown-6),H3PO2.

4. The method for preparing yellow phosphor for white light LED according to claim 1, characterized in that: Weigh the corresponding element compound raw materials according to the chemical formula, dissolve the raw materials in a solvent to react, and the steps further include: The solvent is acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile.

5. The method for preparing yellow phosphor for white light LED according to claim 1, characterized in that: The crude product is treated with a solvent to obtain yellow phosphor, and the step further comprises: The crude product is washed with acetone, N,N-dimethylformamide, dimethyl sulfoxide, methanol or acetonitrile, dried, crushed and sieved to obtain yellow fluorescent powder.

6. A yellow phosphor for white light LED, suitable for the method for preparing the yellow phosphor for white light LED as claimed in claim 1, characterized in that: The yellow phosphor for white light LED has a structural formula of Ma(18-crown-6)bCucId·Xe·fH2O, wherein M is composed of at least one of Mg, Ca, Sr, and Ba, X is composed of at least one of CH3OH, C3H7NO, C2H6OS, H3PO2, C3H6O, and CH3CN, and a, b, c, d, e, and f are molar coefficients in the range of 1≤a≤3, 1≤b≤2, 1≤c≤6, 2≤d≤8, 0≤e≤3, and 1≤f≤6.

7. A white light LED device, suitable for the yellow phosphor for white light LED as claimed in claim 6, characterized in that: The invention comprises a blue light emitting chip and yellow fluorescent powder arranged on the blue light emitting chip.

8. The white light LED device according to claim 7, characterized in that: The yellow fluorescent powder is mixed with UV glue or PDMS colloid and then packaged on the blue light emitting chip.

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