A method using In 3+ Doping control of SrGa2O4:Dy 3+ Methods for assessing the luminescence properties of phosphors

Abstract

This invention discloses a method utilizing In 3+ Doping control of SrGa2O4:Dy 3+ The method for determining the luminescent properties of phosphors includes the following steps: 1. Based on the chemical formula: Sr 1‑x Ga 2‑y O4:xDy 3+ ,yIn 3+ Strontium carbonate, gallium oxide, dysprosium oxide, and indium oxide were weighed out as raw materials according to the following molar ratios: 1. The weighed raw materials were placed in an agate mortar, and alcohol was added to assist grinding, ensuring thorough mixing of the sample. 2. The uniformly mixed raw materials were poured into an alumina crucible, covered, and placed in a muffle furnace. The mixture was heated to 1400 °C and sintered at this temperature for 10 hours in an air atmosphere. 3. After sintering at this temperature, the mixture was cooled to room temperature. 4. The cooled sample was removed, ground, and sieved through a 200-mesh sieve to obtain In. 3+ With Dy 3+ Co-doped SrGa2O4 yellow phosphor. The phosphor prepared by this method shows significant improvements in both luminescence intensity and fluorescence lifetime.

Description

Technical Field

[0001] This invention relates to a method for regulating the performance of luminescent materials, specifically to the process of SrGa2O4:Dy 3+ In doping in phosphor 3+ Ions, specifically ion doping technology, which aims to enhance luminescence intensity and fluorescence lifetime, belongs to the field of luminescent materials technology. Background Technology

[0002] Light-emitting diodes (LEDs), as a new generation of solid-state lighting sources, have outstanding advantages such as long lifespan, high luminous efficacy, energy saving, and environmental friendliness. Currently, the realization of mainstream white LEDs mainly relies on the "blue LED chip + yellow phosphor" technical route. This involves using blue light emitted from a blue LED chip to excite yellow phosphor, and the resulting yellow light mixes with unabsorbed blue light to form white light. Therefore, the luminous performance of the yellow phosphor directly determines key indicators of white LEDs such as luminous efficiency, color temperature, and color rendering index. Developing high-performance yellow phosphors has become one of the core issues in this field.

[0003] Trivalent dysprosium (Dy³⁺) is an important rare-earth luminescent center, its emission originating from the ff transition within the 4f electron shell. The emission spectrum of Dy³⁺ is typically in the range of 480 nm (blue light). 4 F9 / 2 → 6 H 15 / 2) and 575 nm (yellow light, 4 F9 / 2 → 6 H 13 The Dy³⁺ ion exhibits two characteristic peaks near the α-ray peak, with the yellow light emission intensity significantly higher than the blue light emission. Therefore, the Dy³⁺ ion is highly suitable as an activating ion for yellow phosphors. SrGa₂O₄ gallate is a high-performance fluorescent matrix material that can be used to dop Dy³⁺ and excite its characteristic luminescence. However, existing studies have shown that the luminous efficiency of Dy³⁺ in the SrGa₂O₄ matrix is ​​low, with its emission intensity comparable to that of the matrix itself, which severely limits the practical application of this material in white LEDs. Summary of the Invention

[0004] To address the issue of Dy in existing SrGa2O4:Dy³⁺ phosphors 3+ The low efficiency of ion energy transfer leads to Dy 3+ To address the problem of low ion emission efficiency, this invention provides a method for controlling luminescence performance through ion co-doping. This method involves co-doping In into a SrGa2O4 matrix. 3+ Ions and Dy 3+ Ions, enhancing matrix to Dy 3+ The energy transfer efficiency of ions, thus obtaining better Dy 3+This method modulates the fluorescence lifetime of ion emission, thereby significantly increasing the fluorescence intensity of Dy in SrGa2O4:Dy³⁺. 3+ The characteristic emission peak of ions enables high-efficiency yellow light emission, which is expected to be applied in white LEDs.

[0005] The technical solution of the present invention is as follows: In a first aspect, the present invention provides a phosphor, wherein the phosphor is based on SrGa2O4 and co-doped with In. 3+ Ions and Dy 3+ Ions, enhancing matrix to Dy 3+ The energy transfer efficiency of ions is increased to obtain higher Dy. 3+ Ion luminescence intensity and / or fluorescence lifetime

[0006] Furthermore, the chemical formula of the phosphor is Sr 1-x Ga 2-y O4:xDy 3+ ,yIn 3+ , of which 0 <x≤0.02,0<y≤0.05。

[0007] Preferably, x = 0.01 and y = 0.01-0.03; more preferably, x = 0.01 and y = 0.02.

[0008] Secondly, the present invention provides a method for preparing fluorescence analysis, comprising the following steps: Step 1: Based on the chemical formula: Sr 1-x Ga 2-y O4:xDy 3+ ,yIn 3+ Strontium carbonate (SrCO3, analytical grade), gallium oxide (Ga2O3, analytical grade), dysprosium oxide (Dy2O3, analytical grade) and indium oxide (In2O3, analytical grade) were weighed as raw materials in the following molar ratios: Step 2: Place the weighed raw materials into an agate mortar and add 1 mL of alcohol to assist grinding. Grind for 30 minutes to ensure the sample is fully mixed. Step 3: Pour the thoroughly mixed raw materials into a 10 mL alumina crucible, cover it, and place it in a muffle furnace for heating in an air atmosphere. The muffle furnace heating program is as follows: increase the temperature to 200 °C at a rate of 5 °C / min, then to 1000 °C at a rate of 10 °C / min, and finally to 1400 °C at a rate of 3 °C / min. Sinter at this temperature for 10 h. Step 4: After the isothermal sintering is completed, set the muffle furnace to cool down to 1000 ℃ at a rate of 5 ℃ / min, and then stop the power supply to the muffle furnace to allow the material to cool naturally to room temperature inside the furnace. Step 5: Remove the cooled sample and place it in an agate mortar, grinding it into a fine powder. Sift the sample through a 200-mesh sieve to obtain In. 3+ Ions and Dy 3+ Yellow phosphor of SrGa2O4 co-doped with ions.

[0009] Beneficial Effects: This invention proposes co-doping In³⁺ into SrGa₂O₄:Dy³⁺ phosphor. By introducing In³⁺, the local crystal field environment of Dy³⁺ ions is altered, effectively enhancing the energy transfer efficiency from the matrix to Dy³⁺, thereby significantly improving the yellow characteristic emission intensity of Dy³⁺. Simultaneously, this doping strategy also extends the fluorescence lifetime. The performance modulation method provided by this invention can significantly improve the luminescence performance of SrGa₂O₄:Dy³⁺ phosphor, achieving efficient excitation of Dy³⁺ in the SrGa₂O₄ matrix and producing strong yellow emission. This is expected to provide an effective fluorescent material solution for the development of high-performance white LEDs, possessing significant research value and application prospects. This invention, through simple In... 3+ Ions and Dy 3+ Ions are co-doped in the SrGa2O4 matrix via In 3+ Ion doping enhances matrix Dy 3+ Ion transfer efficiency, achieving Dy 3+ The enhanced luminescence intensity and controlled fluorescence lifetime of the ions make them promising candidates for use as yellow phosphors in white LED lighting devices. Attached Figure Description

[0010] Figure 1 Different concentrations of In 3+ Ions and 0.01 Dy 3+ X-ray diffraction pattern of ion-co-doped SrGa2O4 phosphor.

[0011] Figure 2 Different concentrations of In 3+ Ions and 0.01 Dy 3+ Emission spectrum of ion-co-doped SrGa2O4 phosphor.

[0012] Figure 3 SrGa2O4:0.01Dy 3+ With SrGa2O4:0.01Dy 3+ 0.02In 3+ CIE color coordinate diagram of phosphor.

[0013] Figure 4 Different concentrations of In 3+ Ions and 0.01 Dy 3+ Fluorescence decay curve of ion-co-doped SrGa2O4 phosphor.

[0014] Figure 5 Schematic diagram of the preparation process of the phosphor of the present invention. Specific embodiments

[0015] The present invention will be clearly and completely described in detail below with reference to the accompanying drawings and embodiments.

[0016] The chemical formula of the phosphor prepared by the present invention is Sr 1-x Ga 2-y O4:xDy 3+ ,yIn 3+ , where 0 < x ≤ 0.02 and 0 < y ≤ 0.05. This chemical formula does not mean that the phosphor is non-electroneutral, but is a shorthand way to illustrate the proportion of the doping elements; actually, In 3+ substitutes Ga 3+ in an equivalent substitution, while Dy 3+ substitutes Sr 2+ in a heterovalent substitution. After the heterovalent substitution, oxygen needs to be introduced for charge compensation to maintain electroneutrality. The precise chemical formula is Sr 1-x Ga 2-y O<00​​​​​​​​​​​​​​​​​​​​​​​Step 4: After the isothermal sintering is completed, set the muffle furnace to cool down to 1000 ℃ at a rate of 5 ℃ / min, and then stop the power supply to the muffle furnace to allow the material to cool naturally to room temperature inside the furnace. Step 5: Remove the cooled sample and place it in an agate mortar. Grind it into a fine powder. Sift the sample through a 200-mesh sieve to obtain Dy. 3+ The ion-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ .

[0018] Example 2 In this example, the calculation is based on the synthesis of 2 mmol of SrGa2O4 fluorescent product, according to the formula Sr 0.99 Ga 1.99 O4:0.01Dy 3+ 0.01In 3+ Strontium carbonate (SrCO3, 0.00198 mol, 0.2923 g), gallium oxide (Ga2O3, 0.00199 mol, 0.3730 g), dysprosium oxide (Dy2O3, 0.00001 mol, 0.0037 g), and indium oxide (In2O3, 0.00001 mol, 0.0028 g) were weighed as raw materials according to the molar ratios specified in Example 1. Other steps were the same as in Example 1, and finally, In was obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.01In 3+ .

[0019] Example 3 In this example, the calculation is based on the synthesis of 2 mmol of SrGa2O4 fluorescent product, according to the formula Sr 0.99 Ga 1.98 O4:0.01Dy 3+ 0.02In 3+ Strontium carbonate (SrCO3, 0.00198 mol, 0.2923 g), gallium oxide (Ga2O3, 0.00198 mol, 0.3711 g), dysprosium oxide (Dy2O3, 0.00001 mol, 0.0037 g), and indium oxide (In2O3, 0.00002 mol, 0.0056 g) were weighed as raw materials according to the molar ratios specified in Example 1. Other steps were the same as in Example 1, and finally, In was obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.01In3+ The other steps are the same as in Example 1, and finally In is obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.02In 3+ .

[0020] Example 4 In this example, the calculation is based on the synthesis of 2 mmol of SrGa2O4 fluorescent product, according to the formula Sr 0.99 Ga 1.97 O4:0.01Dy 3+ 0.03In 3+ Strontium carbonate (SrCO3, 0.00198 mol, 0.2923 g), gallium oxide (Ga2O3, 0.00197 mol, 0.3692 g), dysprosium oxide (Dy2O3, 0.00001 mol, 0.0037 g), and indium oxide (In2O3, 0.00003 mol, 0.0084 g) were weighed as raw materials according to the molar ratios specified in Example 1. Other steps were the same as in Example 1, and finally, In was obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.03In 3+ .

[0021] Example 5 In this example, the calculation is based on the synthesis of 2 mmol of SrGa2O4 fluorescent product, according to the formula Sr 0.99 Ga 1.96 O4:0.01Dy 3+ 0.04In 3+ Strontium carbonate (SrCO3, 0.00198 mol, 0.2923 g), gallium oxide (Ga2O3, 0.00196 mol, 0.3674 g), dysprosium oxide (Dy2O3, 0.00001 mol, 0.0037 g), and indium oxide (In2O3, 0.00004 mol, 0.0111 g) were weighed as raw materials according to the molar ratios specified in Example 1. Other steps were the same as in Example 1, and finally, In was obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.04In 3+ .

[0022] Example 6 In this example, the calculation is based on the synthesis of 2 mmol of SrGa2O4 fluorescent product, according to the formula Sr 0.99 Ga 1.95 O4:0.01Dy 3+ 0.05In 3+ Strontium carbonate (SrCO3, 0.00198 mol, 0.2923 g), gallium oxide (Ga2O3, 0.00195 mol, 0.3654 g), dysprosium oxide (Dy2O3, 0.00001 mol, 0.0037 g), and indium oxide (In2O3, 0.00005 mol, 0.0140 g) were weighed as raw materials according to the molar ratios specified in Example 1. Other steps were the same as in Example 1, and finally, In was obtained. 3+ Ions and Dy 3+ The ion-co-doped yellow SrGa₂O₄ phosphor is designated as SrGa₂O₄-0.01Dy. 3+ -0.05In 3+ .

[0023] test The six samples from Examples 1-6 above were tested using XRD, emission spectroscopy, fluorescence spectroscopy, etc., and the results are as follows: Figure 1-4 As shown: Figure 1 Different concentrations of In prepared for this invention 3+ Ions and 0.01 Dy 3+ The X-ray diffraction (XRD) pattern of ion-co-doped SrGa2O4 phosphor shows no impurity peaks, proving that In... 3+ Ions and Dy 3+ Ion co-doping did not alter the SrGa2O4 matrix phase. Emission spectra of the series of samples ( Figure 2 Proof In 3+ Ion doping significantly increased the Dy content in the sample 3+ Emission intensity of ions. CIE chromaticity diagram ( Figure 3 Proof of SrGa2O4:0.01Dy 3+ 0.02In 3+ The phosphor emits light primarily in the yellow light region. 3+ Ions effectively regulate Dy 3+ The luminescence color of SrGa2O4 doped phosphor. Different concentrations of In... 3+ Ions and 0.01 Dy 3+ Fluorescence decay curve of ion-co-doped SrGa2O4 phosphor ( Figure 4 Proof In 3+ Ion doping can effectively modulate its fluorescence lifetime. From the above data, it can be concluded that when the strontium gallate matrix is ​​doped with 0.01 Dy... 3+and 0.02 In 3+ At this time, the phosphor exhibits optimal luminescence performance and the longest fluorescence lifetime.

Claims

1. A fluorescent powder, characterized in that, The phosphor uses SrGa2O4 as a matrix and co-dops In. 3+ Ions and Dy 3+ ion.

2. The phosphor according to claim 1, characterized in that, The phosphor has the chemical formula Sr 1-x Ga 2-y O4:xDy 3+ ,yIn 3+ , of which 0 <x≤0.02,0<y≤0.05。 3. The phosphor according to claim 2, characterized in that, The values ​​are x=0.01 and y=0.01-0.

03.

4. The phosphor according to claim 2, characterized in that, The values ​​are x=0.01 and y=0.

02.

5. The method for preparing the phosphor as described in claim 4, characterized in that, Includes the following steps: Step 1: Based on the chemical formula Sr 0.99 Ga 1.98 O4:0.01Dy 3+ 0.02In 3+ Strontium carbonate, gallium oxide, dysprosium oxide, and indium oxide were weighed out as raw materials in the molar ratios specified above. Step 2: Place the weighed raw materials into an agate mortar and add alcohol to assist grinding. Grind for a certain period of time to ensure the sample is fully mixed. Step 3: Pour the well-mixed raw materials into an alumina crucible, cover it, and place it in a muffle furnace. Set the heating program and heat it to 1400 ℃ in an air atmosphere for sintering. Step 4: After sintering, set the muffle furnace to cool down to 1000 ℃ at a rate of 5 ℃ / min, then stop the power supply to the muffle furnace and allow the material to cool naturally to room temperature inside the furnace. Step 5: Remove the cooled sample and place it in an agate mortar. Grind it into a fine powder. Sift the sample through a 200-mesh sieve to obtain In. 3+ Ions and Dy 3+ Yellow phosphor of SrGa2O4 co-doped with ions.

6. The method for preparing phosphor according to claim 5, characterized in that, The heating procedure for the third step is as follows: the muffle furnace is heated to 200 ℃ at a heating rate of 5 ℃ / min, then to 1000 ℃ at a heating rate of 10 ℃ / min, and then to 1400 ℃ at a heating rate of 3 ℃ / min, and sintered at this temperature for 10 h.

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