Aluminum ion and magnesium ion co-doped experimental analysis method and fluorescent material

Abstract

The invention relates to the technical field of fluorescent materials, in particular to an aluminum ion and magnesium ion co-doped experimental analysis method and a fluorescent material. The experimental analysis method comprises the following steps: analyzing the fluorescence intensity, fluorescence lifetime and crystal structure of an undoped fluorescent material, an aluminum ion single-doped fluorescent material, a magnesium ion single-doped fluorescent material and an aluminum ion and magnesium ion co-doped fluorescent material; the analysis results of the influence of single doping and co-doping of the aluminum ions and the magnesium ions on the luminous intensity of the fluorescent material, the influence of the service life and the microscopic regulation and control effect of a crystal structure are obtained, and then the advantages of co-doping of the aluminum ions and the magnesium ions relative to non-doping and single doping of the aluminum ions and the magnesium ions are determined. The method can assist in selecting a doping scheme of aluminum ions and magnesium ions, provides theoretical support for preparation of an aluminum ion and magnesium ion co-doped fluorescent material, and is beneficial to assisting in improving the efficiency and effect of preparation of the fluorescent material.

Description

Technical Field

[0001] The present invention relates to the field of fluorescent materials, and in particular to an experimental analysis method for co-doping aluminum ions and magnesium ions and a fluorescent material. Background Art

[0002] Rare earth-doped luminescent materials, with their unique photoluminescence, upconversion, and downconversion properties, play an important role in lighting, display, biomedicine, and optical communications. As a key matrix for rare earth luminescent materials, Y2O3 has become a hot topic in research and application due to its low phonon energy and excellent thermal stability.

[0003] The luminescence properties of rare earth ion doping are mainly due to the energy level transition of its 4f electrons, especially Er 3+ ions, whose upconversion luminescence process is usually driven by ground state absorption (GSA), excited state absorption (ESA) and cross energy transfer (ETU) mechanisms. 3+ The transition cross section is small, the luminescence efficiency is low, and the performance improvement of single-ion doped materials is limited.

[0004] Domestic and foreign scholars have conducted extensive research on rare earth doped materials, especially in the areas of crystal field regulation, defect repair and luminescence performance optimization. Zhang et al. studied Mg 2+ γ-AlON:Er 3+ The influence of upconversion luminescence on materials, the discovery of Mg 2+ Doping significantly reduces the non-radiative transition rate and enhances the luminescence intensity of the material. Huang et al. 2+ Doped KMnF3:Yb 3+ / Er 3+ Nanocrystals optimize the local crystal field environment and significantly improve the intensity of single red luminescence. 3+ / Yb 3+ The preparation and properties of transparent ceramics, further explored the regulation effect of crystal field environment on rare earth luminescence properties. Ran Q focused on the analysis of different Al 3+ The influence of doping concentration on material properties. Regarding luminescence performance, existing studies have found that excitation power and temperature have an important influence on the luminescence efficiency of doped materials. Sinha et al. systematically studied Mg 2+ Doping Yb 3+ / Er 3+ The luminescence enhancement effect of co-doped molybdate materials was studied, and the effect of laser power on temperature sensitivity was explored.2+ Doping not only improves the fluorescence intensity, but also optimizes the thermal stability, making the fluorescent material have better application performance under high temperature conditions.

[0005] Co-doping technology has become a research hotspot in recent years. For example, Sun et al. + / Mg 2+ Co-doped Gd2Mo3O9:Er 3+ / Yb 3 + materials, significantly enhanced the up-conversion luminescence performance and improved the temperature sensing capability. 2+ Ho doping 3+ / Yb 3+ / Tm 3+ Co-doping LiNbO3 single crystals improves the white light emission stability of the material. Wen Cheng studied Y2O3:Eu by co-precipitation method 3+ The surface modification of the material improves its luminescence performance. Liu Shuang et al. optimized the Y2O3:Eu by adjusting the preparation process. 3+ The luminescence properties of red phosphors. Zhai Jiali discussed the Y2O3:Yb 3+ / Er 3+ The application of nanoparticles in latent fingerprint visualization has further expanded their practical functions.

[0006] The applicant found in actual research that Al 3+ and Mg 2+ Co-doped fluorescent materials have excellent upconversion luminescence efficiency. However, Al 3+ and Mg 2+ Co-doping may have a negative impact on other aspects of the fluorescent material. 3+ and Mg 2+ The experimental analysis method of co-doped fluorescent material performance cannot effectively determine the Al 3+ and Mg 2+ Co-doping versus no doping and Al 3+ and Mg 2+ The advantage of single doping makes it difficult to select the doping scheme of aluminum ions and magnesium ions based on the actual needs of fluorescent materials, which 3+ and Mg 2+ The preparation of co-doped fluorescent materials brings difficulties. Summary of the Invention

[0007] In view of the shortcomings of the above-mentioned prior art, the technical problem to be solved by the present invention is: how to provide an experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent materials, by analyzing the intensity, lifespan and crystal structure of the fluorescent materials, obtaining analytical results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity, lifespan and crystal structure micro-control of the fluorescent materials, thereby effectively determining the advantages of co-doping of aluminum ions and magnesium ions over no doping and single doping of aluminum ions and magnesium ions, and being able to assist in selecting the doping scheme of aluminum ions and magnesium ions, providing theoretical support for the preparation of aluminum ion and magnesium ion co-doped fluorescent materials, which is conducive to assisting in improving the efficiency and effect of fluorescent material preparation. Moreover, through this experimental analysis method, it was found that co-doping of aluminum ions and magnesium ions can significantly improve the up-conversion luminescence efficiency and crystal structure stability of the fluorescent material and ensure the excited state lifetime of the fluorescent material to a certain extent.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] An experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent materials, comprising:

[0010] S1: preparing undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials;

[0011] S2: Analyze the fluorescence intensity of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the luminescence intensity of fluorescent materials;

[0012] S3: Analyze the fluorescence lifetime of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the lifetime of fluorescent materials;

[0013] S4: Analyze the crystal structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analytical results of the microscopic regulation effect of aluminum ion and magnesium ion single-doping and co-doping on the lattice structure of fluorescent materials;

[0014] S5: Analyze the Rietveld refined structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the changes in the crystal structure of fluorescent materials caused by aluminum ion and magnesium ion single-doping and co-doping;

[0015] S6: Based on the analysis of the effects of single and co-doping of aluminum and magnesium ions on the luminescence intensity, lifetime, micro-control of crystal structure, and changes in crystal structure of fluorescent materials, the advantages of co-doping of aluminum and magnesium ions over no doping and single doping of aluminum and magnesium ions are analyzed;

[0016] S7: Based on the requirements of fluorescent materials, combined with the analysis results of the advantages of co-doping with aluminum ions and magnesium ions over no doping and single doping with aluminum ions and magnesium ions, a doping scheme of aluminum ions and magnesium ions is selected, and the corresponding fluorescent materials are prepared.

[0017] Preferably, in step S2, the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity of the fluorescent material include:

[0018] 1) Compared with undoped fluorescent materials, aluminum ion-doped fluorescent materials have higher luminescence intensity; aluminum ions enhance the green light emission intensity of the fluorescent materials;

[0019] 2) Compared with undoped fluorescent materials, magnesium ions alone doped fluorescent materials have improved luminescence intensity; magnesium ions enhance the red light emission intensity of the fluorescent material;

[0020] 3) The green light emission intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is several times that of the fluorescent material doped with aluminum ions alone;

[0021] 4) The red light emission intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is several times that of the fluorescent material doped with magnesium ions alone.

[0022] Preferably, in step S6, the advantage determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity of the fluorescent material is that the luminous intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the undoped fluorescent material and the fluorescent material single-doped with aluminum ions and magnesium ions, that is, the co-doping of aluminum ions and magnesium ions improves the up-conversion luminous efficiency of the fluorescent material compared with the undoped fluorescent material and the single doping with aluminum ions and magnesium ions.

[0023] Preferably, in step S3, the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the life of the fluorescent material are as follows:

[0024] 1) Compared with undoped fluorescent materials, aluminum ion single-doped fluorescent materials extend the excited state lifetime;

[0025] 2) Compared with undoped fluorescent materials, single-magnesium ion doped fluorescent materials have shorter excited state lifetimes;

[0026] 3) The lifetime of the aluminum ion and magnesium ion co-doped fluorescent material is shorter than the excited state lifetime of the aluminum ion single doped fluorescent material and the undoped fluorescent material, and is longer than the excited state lifetime of the magnesium ion single doped fluorescent material.

[0027] Preferably, in step S6, the advantage determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the lifespan of the fluorescent material is that the lifespan of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent material doped with magnesium ions alone, that is, the co-doping of aluminum ions and magnesium ions alleviates the trend of shortening of the excited state lifetime caused by magnesium ion doping through the introduction of aluminum ions.

[0028] Preferably, in step S4, the analysis results of the microscopic control effect of single doping and co-doping of aluminum ions and magnesium ions on the lattice structure of the fluorescent material include:

[0029] 1) Compared with undoped fluorescent materials, the diffraction peak of aluminum ion-doped fluorescent materials shifts toward low angles and the interplanar spacing increases, i.e., the lattice expands.

[0030] 2) Compared with the undoped fluorescent material, the main diffraction peak of the magnesium ion single-doped fluorescent material shifts to the high-angle direction, and the interplanar spacing becomes smaller, that is, the lattice shrinks;

[0031] 3) Compared with the undoped fluorescent material, the overall distribution of the main diffraction peak of the aluminum ion and magnesium ion co-doped fluorescent material does not change, and the crystal structure is stable.

[0032] Preferably, in step S6, the advantage determined based on the analysis results of the microscopic regulatory effects of single doping and co-doping of aluminum ions and magnesium ions on the lattice structure of the fluorescent material is that the crystal structure of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent material single doped with aluminum ions and the fluorescent material single doped with magnesium ions, that is, the co-doping of aluminum ions and magnesium ions improves the crystal structure stability of the fluorescent material compared with the undoped fluorescent material and the single doping of aluminum ions and magnesium ions.

[0033] Preferably, in step S5, the analysis results of the changes in the crystal structure of the fluorescent material caused by single doping and co-doping of aluminum ions and magnesium ions include:

[0034] 1) In aluminum ion-doped fluorescent materials, the lattice expansion becomes more obvious with the increase of aluminum ion concentration;

[0035] 2) In the magnesium ion single-doped fluorescent material, the lattice contraction becomes more obvious with the increase of magnesium ion concentration;

[0036] 3) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice shrinks when the aluminum ion concentration is low and the magnesium ion concentration is high;

[0037] 4) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice expands when the concentration of aluminum ions is high and the concentration of magnesium ions is low;

[0038] 5) In the fluorescent material co-doped with aluminum ions and magnesium ions, the crystal structure is stable in the case of high concentrations of aluminum ions and high concentrations of magnesium ions.

[0039] Preferably, in step S6, the advantages determined based on the analysis results of the changes in the crystal structure of the fluorescent material by single doping and co-doping of aluminum ions and magnesium ions are: the crystal structure of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent material single doped with aluminum ions and magnesium ions, and the crystal structure stability of the fluorescent material co-doped with high concentration aluminum ions and high concentration magnesium ions is the best.

[0040] An aluminum ion and magnesium ion co-doped fluorescent material is prepared based on experimental analysis results of an experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent materials.

[0041] Compared with the prior art, the experimental analysis method of aluminum ion and magnesium ion co-doping in the present invention has the following beneficial effects:

[0042] The present invention analyzes the fluorescence intensity, fluorescence lifetime and crystal structure of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials and aluminum ion and magnesium ion co-doped fluorescent materials, and obtains the analysis results of the influence of aluminum ion, magnesium ion single-doping and co-doping on the luminous intensity of fluorescent materials, the influence of lifespan and the microscopic control effect of crystal structure, thereby effectively determining the advantages of aluminum ion and magnesium ion co-doping over no doping and aluminum ion and magnesium ion single-doping, and can assist in selecting the doping scheme of aluminum ions and magnesium ions, and provide theoretical support for the preparation of aluminum ion and magnesium ion co-doped fluorescent materials, which is conducive to assisting in improving the efficiency and effect of fluorescent material preparation. Through this experimental analysis method, it is found that: first, the luminous intensity of aluminum ion and magnesium ion co-doped fluorescent materials is better than that of undoped fluorescent materials and aluminum ion and magnesium ion single-doped fluorescent materials, that is, aluminum ion and magnesium ion co-doping significantly improves the up-conversion luminous efficiency of fluorescent materials compared to undoped fluorescent materials and aluminum ion and magnesium ion single-doping. Secondly, the lifespan of aluminum ion and magnesium ion co-doped fluorescent materials is better than that of magnesium ion single-doped fluorescent materials, that is, aluminum ion and magnesium ion co-doping alleviates the trend of shortening the excited state lifetime brought about by magnesium ion doping by the introduction of aluminum ions. Finally, the crystal structure of the aluminum- and magnesium-ion co-doped fluorescent material was superior to that of the aluminum- and magnesium-ion-single-doped fluorescent materials. This indicates that aluminum- and magnesium-ion co-doping improves the crystal structure stability of the fluorescent material compared to the undoped fluorescent material and the aluminum- and magnesium-ion-single-doped fluorescent materials. Furthermore, this experimental analysis method revealed that aluminum- and magnesium-ion co-doping significantly improves the upconversion luminescence efficiency and crystal structure stability of the fluorescent material, while also ensuring the excited-state lifetime of the fluorescent material to a certain extent.

[0043] Based on the analysis of the advantages of co-doping with aluminum ions and magnesium ions over no doping and single doping with aluminum ions and magnesium ions, the present invention further analyzes the Rietveld refined structures of undoped fluorescent materials, single aluminum ion doped fluorescent materials, single magnesium ion doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtains analysis results of the changes in the crystal structure of the fluorescent materials caused by single and co-doping with aluminum ions and magnesium ions, thereby effectively determining the concentration of aluminum ion and magnesium ion co-doping, and further improving the up-conversion luminescence efficiency of the aluminum ion and magnesium ion co-doped fluorescent materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to make the purpose, technical solutions and advantages of the invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0045] Figure 1 This is the logic block diagram of the experimental analysis method for co-doping of aluminum ions and magnesium ions.

[0046] Figure 2 (a) Al-doped 3+ Fluorescence intensity histogram; Figure 2 (b) Single Mg doping 2+ Fluorescence intensity histogram; Figure 2 (c) is the fluorescence intensity histogram of EMAL series materials.

[0047] Figure 3 (a) Y2O3:Er 3+ Material energy level lifetime diagram; Figure 3 (b) Al-doped 3+ Material energy level lifetime diagram; Figure 3 (c) Single Mg doping 2+ Material energy level lifetime diagram; Figure 3 (d) is Al 3+ / Mg 2+ Energy level lifetime diagram of co-doped materials.

[0048] Figure 4 (a) Al-doped 3+ XRD pattern of Figure 4 (b) Al-doped 3+ A magnified view of the local peak position; Figure 4 (c) Single Mg doping 2+ XRD pattern of Figure 4 (d) Single Mg doping 2+ A magnified view of the local peak position.

[0049] Figure 5 (a) is the XRD pattern of EMAL series materials; Figure 5 (b) is an enlarged view of the local peak position.

[0050] Figure 6 (a)-(f) correspond to the refined images of S1, S2, S4, S5, S7, EMAL-1, EMAL-2, and EMAL-3, respectively.

[0051] Figure 7 (a) Schematic diagram of the lattice of EMAL-1 material; Figure 7 (b) Schematic diagram of the lattice of EMAL-2 material; Figure 7 (c) Schematic diagram of the lattice of EMAL-3 material. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but only represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0053] It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not require further definition or explanation in subsequent figures. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate positions or relationships based on the positions or relationships shown in the figures, or the positions or relationships in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation, and are therefore not to be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and are not to be construed as indicating or implying relative importance. Furthermore, terms such as "horizontal" and "vertical" do not imply that a component is absolutely horizontal or overhanging, but rather may be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather may be slightly tilted. In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0054] The following is a further detailed description through specific implementation methods:

[0055] Example 1:

[0056] This embodiment discloses an experimental analysis method for a fluorescent material co-doped with aluminum ions and magnesium ions.

[0057] like Figure 1 As shown, an experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent material includes:

[0058] S1: Preparation of undoped fluorescent materials (Y2O3:Er 3+ fluorescent materials), and aluminum ion single-doped fluorescent materials with different doping concentrations (Y2O3:Er 3+ / Al 3+ Fluorescent materials), magnesium ion single doped fluorescent materials (Y2O3:Er 3+ / Mg 2+ Fluorescent materials), aluminum ion and magnesium ion co-doped fluorescent materials (Y2O3:Er 3+ / Mg 2+ / Al3+ fluorescent materials);

[0059] S2: Analyze the fluorescence intensity of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the luminescence intensity of fluorescent materials;

[0060] S3: Analyze the fluorescence lifetime of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the lifetime of fluorescent materials;

[0061] S4: Analyze the crystal structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analytical results of the microscopic regulation effect of aluminum ion and magnesium ion single-doping and co-doping on the lattice structure of fluorescent materials;

[0062] S5: Analyze the Rietveld refined structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the changes in the crystal structure of fluorescent materials caused by aluminum ion and magnesium ion single-doping and co-doping;

[0063] In this embodiment, Rietveld refinement is a crystal structure analysis method based on full-spectrum fitting. It compares the experimentally measured diffraction pattern (such as the XRD pattern) with the theoretical diffraction pattern calculated based on the crystal structure model point by point. The parameters in the crystal structure model (such as unit cell parameters, atomic positions, atomic occupancy, thermal vibration parameters, etc.) are continuously adjusted using the least squares method to minimize the difference between the calculated and experimental patterns, thereby obtaining a crystal structure model that best fits the experimental data.

[0064] S6: Based on the analysis of the effects of single and co-doping of aluminum and magnesium ions on the luminescence intensity, lifetime, micro-control of crystal structure, and changes in crystal structure of fluorescent materials, the advantages of co-doping of aluminum and magnesium ions over no doping and single doping of aluminum and magnesium ions are analyzed;

[0065] S7: Based on the requirements of fluorescent materials, combined with the analysis results of the advantages of co-doping with aluminum ions and magnesium ions over no doping and single doping with aluminum ions and magnesium ions, a doping scheme of aluminum ions and magnesium ions is selected, and the corresponding fluorescent materials are prepared.

[0066] Specifically:

[0067] 1) When the requirement for the fluorescent material prioritizes upconversion luminescence efficiency, the doping scheme of aluminum ions and magnesium ions is co-doping of aluminum ions and magnesium ions, that is, preparing aluminum ion and magnesium ion co-doped fluorescent materials.

[0068] 2) When the requirements for the fluorescent material prioritize green light emission intensity and have no requirements for red light emission intensity, the doping scheme of aluminum ions and magnesium ions is single aluminum ion doping, that is, preparing a single aluminum ion doped fluorescent material.

[0069] 3) When the requirements for the fluorescent material prioritize red light emission intensity and have no requirements for green light emission intensity, the doping scheme of aluminum ions and magnesium ions is single magnesium ion doping, that is, preparing a single magnesium ion doped fluorescent material.

[0070] 4) When the fluorescent material is required to prioritize fluorescence lifetime, the doping scheme of aluminum ions and magnesium ions is single aluminum ion doping, that is, preparing a single aluminum ion doped fluorescent material.

[0071] 5) When the crystal structure stability is prioritized for the fluorescent material, the doping scheme of aluminum ions and magnesium ions is co-doping of aluminum ions and magnesium ions, that is, preparing aluminum ion and magnesium ion co-doped fluorescent materials.

[0072] 6) When the requirement for the fluorescent material is optimal crystal structure stability, the doping scheme of aluminum ions and magnesium ions is co-doping of aluminum ions and magnesium ions, that is, preparing an aluminum ion and magnesium ion co-doped fluorescent material, and the concentration of aluminum ions in the aluminum ion and magnesium ion co-doped fluorescent material is 4 mol%, and the concentration of magnesium ions is 3 mol%.

[0073] The selection methods of the doping schemes of aluminum ions and magnesium ions in the above 1) to 6) can be freely combined.

[0074] The present invention analyzes the fluorescence intensity, fluorescence lifetime and crystal structure of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials and aluminum ion and magnesium ion co-doped fluorescent materials, and obtains the analysis results of the influence of aluminum ion, magnesium ion single-doping and co-doping on the luminous intensity of fluorescent materials, the influence of lifespan and the microscopic control effect of crystal structure, thereby effectively determining the advantages of aluminum ion and magnesium ion co-doping over no doping and aluminum ion and magnesium ion single-doping, and can assist in selecting the doping scheme of aluminum ions and magnesium ions, and provide theoretical support for the preparation of aluminum ion and magnesium ion co-doped fluorescent materials, which is conducive to assisting in improving the efficiency and effect of fluorescent material preparation. Through this experimental analysis method, it is found that: first, the luminous intensity of aluminum ion and magnesium ion co-doped fluorescent materials is better than that of undoped fluorescent materials and aluminum ion and magnesium ion single-doped fluorescent materials, that is, aluminum ion and magnesium ion co-doping significantly improves the up-conversion luminous efficiency of fluorescent materials compared to undoped fluorescent materials and aluminum ion and magnesium ion single-doping. Secondly, the lifespan of aluminum ion and magnesium ion co-doped fluorescent materials is better than that of magnesium ion single-doped fluorescent materials, that is, aluminum ion and magnesium ion co-doping alleviates the trend of shortening the excited state lifetime brought about by magnesium ion doping by the introduction of aluminum ions. Finally, the crystal structure of the aluminum- and magnesium-ion co-doped fluorescent material was superior to that of the aluminum- and magnesium-ion-single-doped fluorescent materials. This indicates that aluminum- and magnesium-ion co-doping improves the crystal structure stability of the fluorescent material compared to the undoped fluorescent material and the aluminum- and magnesium-ion-single-doped fluorescent materials. Furthermore, this experimental analysis method revealed that aluminum- and magnesium-ion co-doping significantly improves the upconversion luminescence efficiency and crystal structure stability of the fluorescent material, while also ensuring the excited-state lifetime of the fluorescent material to a certain extent.

[0075] Based on the analysis of the advantages of co-doping with aluminum ions and magnesium ions over no doping and single doping with aluminum ions and magnesium ions, the present invention further analyzes the Rietveld refined structures of undoped fluorescent materials, single aluminum ion doped fluorescent materials, single magnesium ion doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtains analysis results of the changes in the crystal structure of the fluorescent materials caused by single and co-doping with aluminum ions and magnesium ions, thereby effectively determining the concentration of aluminum ion and magnesium ion co-doping, and further improving the up-conversion luminescence efficiency of the aluminum ion and magnesium ion co-doped fluorescent materials.

[0076] In order to better introduce the technical solution of the present invention, this embodiment is described through the following parts.

[0077] In this embodiment, X-ray diffraction (XRD) technology is used to study the Al 3+ and Mg 2+ Doping of Y2O3:Er 3+The influence of the crystal structure of the material was studied. The unit cell parameters, grain size and diffraction characteristics of the main crystal planes were extracted through refinement analysis to explore the regulatory effect of doping on the stability of the crystal structure and crystal growth characteristics. The luminescence intensity of each sample was measured using a fluorescence spectrometer to evaluate the changes in the optical properties of the material under different doping conditions and determine the optimal doping ratio. At the same time, combined with time-resolved fluorescence lifetime testing, the Er content in samples with different doping concentrations was compared. 3+ The changing trend of the excited state lifetime is studied, and the mechanism of the influence of crystal structure evolution on luminescence lifetime is further analyzed to provide a theoretical reference for optimizing the structural design and performance improvement of rare earth doped fluorescent materials.

[0078] 1. Sample Preparation

[0079] In this embodiment, Y2O3:Er with different doping concentrations was prepared by sol-gel method. 3+ 、Y2O3:Er 3+ / Al 3+ 、Y2O3:Er 3+ / Mg 2+ and Y2O3:Er 3+ / Mg 2+ / Al 3+ Fluorescent material. The preparation process is as follows:

[0080] First, Er(NO3)3·6H2O, Y(NO3)3·6H2O, C6H9AlO6·2H2O and C4H6MgO4·4H2O and other raw materials are weighed according to the precise stoichiometric ratio and dissolved in deionized water to ensure that the solute is completely dissolved. Subsequently, an appropriate amount of citric acid is added to the solution, and the amount of addition is based on the principle that the molar ratio of cations to citric acid is 1:2, and the pH value of the solution is finely adjusted to 7 using ammonia water to ensure the smooth progress of subsequent reactions. Then, the solution is continuously stirred at a constant temperature of 150°C until a stable yellow-brown precursor is formed. In order to obtain the desired fluorescent material, this precursor is further treated with laser annealing technology. The specific steps are: spread the precursor evenly on an optical platform, and use a 980nm laser to focus on its surface. In the initial stage, the laser power is set to 15W and the spot area is 9mm 2 The precursor was irradiated for approximately 10 seconds, until the color of the precursor gradually changed from brown to white. Subsequently, the laser power was increased to 19W, and the spot diameter was reduced to approximately 3mm. Irradiation was continued until the precursor was completely melted and fused into a dense crystalline structure. In this example, the total laser heating time was optimized to 30 seconds to ensure high-quality fluorescent material.

[0081] 2. Material preparation and composition

[0082] In this example, a series of rare earth doped oxide materials were successfully prepared by the sol-gel method. By precisely controlling the molar ratio of each element, specific optical properties were achieved. Table 1 lists the detailed composition of the prepared materials and their corresponding abbreviations. These materials are mainly composed of yttrium (Y 3+ ) as the matrix material and doped with different concentrations of erbium (Er 3+ ), magnesium (Mg 2 + ) and aluminum (Al 3+ ) ions. Specifically, the EMAL series of materials (such as EMAL-1, EMAL-2, and EMAL-3) aims to explore the effects of different dopant combinations on fluorescence intensity; while the S series of materials (S1 to S8) focuses on studying the effects of a single agent at a fixed yttrium concentration. The data in Table 1 shows the precise molar percentages of each element in each material, providing a solid foundation for subsequent performance characterization and analysis. The materials were prepared using the sol-gel method, and the material composition is as follows:

[0083] Table 1 Detailed composition of the prepared materials and their corresponding abbreviations

[0084]

[0085]

[0086] 3. Sample Characterization Methods

[0087] To fully evaluate the 3+ With Mg 2+ Co-doping of Y2O3:Er 3+ The luminescence properties of fluorescent materials are affected by their crystal structure. This embodiment uses multiple characterization methods to conduct an in-depth analysis from optical behavior to microstructure.

[0088] First, the upconversion emission spectra of each sample were collected under 980nm excitation conditions by fluorescence spectrometer, focusing on the changes in luminescence intensity in the green and red regions to evaluate the effect of different doping conditions on the upconversion luminescence efficiency. Then, the fluorescence lifetime test system was used to measure Er 3+ Ionic 4 I 13 / 2 The excited state lifetime was calculated, and the emission decay curve was fitted with an e-exponential to analyze the regulatory effect of the change in the probability of non-radiative transition on the lifetime, further revealing the regulatory effect of the doping ions on the local crystal field and energy relaxation path. Finally, X-ray diffraction (XRD) was used to test the crystal structure of each sample, and key information such as unit cell parameters, atomic occupancy and fitting residuals were extracted through Rietveld refinement to determine whether the doping ions entered the Y 3+ sites, whether it induces lattice distortion and its impact on the overall structural stability.

[0089] Through the systematic characterization of the above luminescence properties and structural characteristics, it is revealed that Al 3+ With Mg 2+ Co-doping of Y2O3:Er 3+ The synergistic mechanism of material upconversion luminescence enhancement provides theoretical support and experimental basis for the efficient design and performance optimization of rare earth luminescent materials.

[0090] IV. Comparative Analysis of Fluorescence Intensity

[0091] To evaluate the effects of different ion doping on Y2O3:Er 3+ In order to study the effect of regulating the upconversion luminescence performance of materials, this embodiment systematically measured the green and red luminescence intensities of multiple groups of samples under 980nm excitation conditions. The research samples include Al 3+ Single doping, Mg 2+ Single doping and Al 3+ / Mg 2+ Co-doped system.

[0092] The analysis results of the effects of single and co-doping of aluminum and magnesium ions on the luminescence intensity of fluorescent materials include:

[0093] 1) Compared with the undoped fluorescent material, the aluminum ion-doped fluorescent material has a higher luminous intensity; the aluminum ion enhances the green light emission intensity of the fluorescent material. 3+ In the single doping series (S2–S4), Figure 2 As shown in (a), as the doping concentration increases from 1 mol% to 4 mol%, the green and red emission intensities of the samples gradually increase. The luminescence intensity of the highest doped sample S4 increases to about 2.1 times and 2.3 times that of the undoped sample S1, respectively. This indicates that within the current doping concentration range, Al 3+ The introduction of 3+ upconversion luminescence behavior.

[0094] 2) Compared with the undoped fluorescent material, the single-doped fluorescent material of magnesium ion has improved the luminous intensity; magnesium ion enhances the red light emission intensity of the fluorescent material; Mg 2+ The single-doping series (S5–S7) also showed an obvious luminescence enhancement trend, e.g. Figure 2 As shown in (b), the intensity of the red light channel is most significantly improved in S7, which is about 4 times that of S1. 3+ Doping mainly promotes green light enhancement, Mg 2+ The red light channel performs more prominently under doping, indicating that the two ions may have different mechanisms of action in regulating luminescence behavior, but the specific mechanism needs further analysis.

[0095] 3) The green light emission intensity of the aluminum ion and magnesium ion co-doped fluorescent material is several times (2.38 times) that of the aluminum ion single doped fluorescent material; 4) The red light emission intensity of the aluminum ion and magnesium ion co-doped fluorescent material is several times (4 times) that of the magnesium ion single doped fluorescent material. 3+ / Mg 2+ In the EMAL materials of the co-doped system, such as Figure 2 As shown in (b), sample EMAL-3 exhibits the most significant overall luminescence enhancement, with green and red emission intensities reaching approximately 2.38 times and 4 times that of S1, respectively, the highest in the entire series. These results demonstrate that, in the current experimental system, the co-doping strategy outperforms single doping and can significantly improve upconversion luminescence efficiency.

[0096] In summary, the advantages determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity of fluorescent materials are: the luminous intensity of fluorescent materials co-doped with aluminum ions and magnesium ions is better than that of undoped fluorescent materials and single doped with aluminum ions and magnesium ions, that is, co-doping with aluminum ions and magnesium ions (significantly) improves the up-conversion luminous efficiency of fluorescent materials compared with undoped fluorescent materials and single doping with aluminum ions and magnesium ions.

[0097] 5. Fluorescence Lifetime Analysis

[0098] Figure 3 The different doping samples were shown 4 I 13 / 2 → 4 I 15 / 2 The fluorescence lifetime decay curve under the transition is used to reflect the Er 3 + The lifetime (t) of the excited state of ions in the lattice. The red solid line represents the fitting curve, and the black hollow circles represent the experimental data points. By fitting the decay curves with the exponential e, the lifetime parameters of each sample were obtained: the lifetime of the undoped sample S1 is 976 μs; the lifetime of Al 3+ The S4 of the single-doped sample is 1020μs, which is slightly improved; 2+ The S7 lifetime of the single-doped sample is 608μs, which is significantly shortened; 3 + / Mg 2+ The lifetime of the co-doped sample EMAL-3 is 763 μs, which is between S1 and S7.

[0099] Analysis results of the effects of single and co-doping of aluminum ions and magnesium ions on the lifespan of fluorescent materials:

[0100] 1) Compared with undoped fluorescent materials, aluminum ion-doped fluorescent materials have prolonged excited state lifetime. 3+The lifetime of the doped sample (S4) is slightly longer than that of S1, indicating that it has a better effect on Er 3+ Excited-state stability may have a positive effect.

[0101] 2) Compared with the undoped fluorescent materials, the single-doped fluorescent materials of magnesium ions have a shorter excited state lifetime. 2+ In the single-doped sample (S7), the fluorescence lifetime decreases significantly, indicating that under this doping condition, Er 3+ The excited state lifetime is suppressed. However, combined with the aforementioned fluorescence intensity test results, despite the shorter lifetime of the S7 sample, the luminescence intensity does not show a significant attenuation, and even shows an increasing trend. This shows that a shortened lifetime does not necessarily directly mean a decrease in luminous efficiency, and the lifetime change may also be affected by other factors.

[0102] 3) The lifetime of the aluminum ion and magnesium ion co-doped fluorescent material is shorter than that of the aluminum ion single doped fluorescent material and the undoped fluorescent material, but longer than that of the magnesium ion single doped fluorescent material. In the co-doped sample EMAL-3, the lifetime has recovered somewhat compared with S7, but is still lower than S1 and S4, indicating that Al 3+ Doping may alleviate the Mg 2+ The lifetime of the excited state caused by doping tends to shorten. Overall, the lifetime and luminescence intensity of the EMAL-3 sample are both in a relatively good state, demonstrating the potential of the co-doping strategy to regulate luminescence behavior.

[0103] In summary, the advantages determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the lifetime of fluorescent materials are: the lifetime of fluorescent materials co-doped with aluminum ions and magnesium ions is better than that of fluorescent materials doped with magnesium ions alone, that is, the co-doping of aluminum ions and magnesium ions alleviates the trend of shortening of the excited state lifetime caused by magnesium ion doping through the introduction of aluminum ions.

[0104] 6. XRD crystal structure analysis

[0105] In order to further study the effect of different ion doping on Y2O3:Er 3+ In order to investigate the influence of the crystal structure of fluorescent materials, this embodiment conducted X-ray diffraction (XRD) tests on a series of samples and combined the Rietveld refinement method to systematically analyze their crystal phase structure, unit cell parameters and doping ion occupation behavior. 3+ Mg 2+ The single-doping and co-doping behaviors of the two regulatory ions are carried out, focusing on the microscopic regulatory effect of changes in the doping ratio on the crystal structure of the material, thereby providing a structural basis for subsequent changes in luminescence performance.

[0106] from Figure 4It can be clearly seen that all samples exhibit clear and sharp diffraction peaks. The main peak positions are highly consistent with the characteristic peak positions of the standard cubic phase Y2O3 (PDF#41-1105), mainly corresponding to crystal planes such as (222), (400), (440), and (622), indicating that the samples have high crystallinity and the main crystalline phase structure has not changed. This shows that none of the samples doped with a single ion exhibit impurity peaks or second-phase diffraction features, indicating that the doping process did not cause a phase change or the formation of other new phases.

[0107] The results of the analysis of the microscopic regulation of the lattice structure of fluorescent materials by single and co-doping of aluminum and magnesium ions include:

[0108] 1) Compared with the undoped fluorescent material, the diffraction peak of the aluminum ion single-doped fluorescent material shifts (slightly) toward the low-angle direction, and the interplanar spacing increases, that is, the lattice expands (slightly). Figure 4 (a) shows the undoped sample S1 and different concentrations of Al 3+ XRD patterns of doped samples. Figure 4 (b) It can be observed that the diffraction peak of S2 shifts slightly toward the low-angle direction compared to S1, which means that the interplanar spacing increases and the unit cell parameters expand slightly. 3+ The radius is much smaller than Y 3+ However, after entering the crystal lattice, it is easy to cause local stress concentration and lattice distortion, which may induce a certain elastic relaxation or even rearrangement of the surrounding crystal structure, thereby releasing stress, which manifests as a slight expansion of the unit cell on a macroscopic scale.

[0109] 2) Compared with the undoped fluorescent material, the main diffraction peak (overall) of the magnesium ion single-doped fluorescent material shifts toward the high-angle direction, the interplanar spacing becomes smaller, and the unit cell parameters decrease significantly, that is, the lattice shrinks. Figure 4 (c) Undoped sample S1 and samples with different Mg concentrations 2+ XRD patterns of doped samples. Figure 4 Compared with (b), the main diffraction peaks of this group of samples shifted toward the high-angle direction, indicating that the interplanar spacing became smaller and the unit cell parameters decreased significantly, that is, the lattice contracted. 2+ Enter Y 3+ After the sites are formed, a uniform compression of the crystal structure will be induced without obvious local distortion or relaxation effect, which will lead to the overall shrinkage of the unit cell and the shift of the diffraction peak to high angles.

[0110] 3) Compared with the undoped fluorescent material, the overall distribution of the main diffraction peak of the aluminum ion and magnesium ion co-doped fluorescent material did not change significantly. Only when the local peak position was magnified, the main peak position was found to shift (slightly) toward the low-angle direction. The crystal structure was (relatively) stable. Figure 5In (a), the diffraction peaks are still well distributed and no impurity phase is generated, indicating that even under high doping concentration conditions, Al 3+ With Mg 2+ It can still enter the Y2O3 lattice synergistically to form a stable solid solution. This dual ion cooperative doping does not destroy the overall stability of the crystal structure. Instead, it may alleviate local stress concentration through the structural cooperative regulation mechanism, thereby achieving optimized stability of the crystal structure. Compared with the undoped sample S1, all doped samples (EMAL-1, EMAL-2, EMAL-3) did not show significant changes in the overall distribution of the main diffraction peaks, but through Figure 5 (b) Zooming in on the local peak position clearly reveals a slight shift in the main peak position of the doped samples toward lower angles. According to Bragg's law, this shift in peak position toward lower angles indicates an increase in the interplanar spacing of the sample, and an overall expansion of the unit cell constant.

[0111] XRD patterns clearly demonstrate that, under the doping conditions established in this example, the samples prepared maintain a single cubic Y2O3 phase structure with excellent crystallinity and phase purity. The dopant ions are likely to have successfully incorporated into the crystal lattice and formed a solid solution. The doping-induced peak shifts and changes in peak shape suggest the presence of localized lattice distortion. These results provide fundamental support for further refinement and analysis to explore changes in unit cell parameters, site occupancy behavior, and structural stability.

[0112] In summary, the advantages determined based on the analysis results of the microscopic regulation effect of single doping and co-doping of aluminum ions and magnesium ions on the lattice structure of fluorescent materials are: the crystal structure of fluorescent materials co-doped with aluminum ions and magnesium ions is better than that of single doping with aluminum ions and single doping with magnesium ions, that is, co-doping with aluminum ions and magnesium ions improves the crystal structure stability of fluorescent materials compared with undoped fluorescent materials and single doping with aluminum ions and magnesium ions.

[0113] 7. Rietveld Refinement Structure Analysis

[0114] In order to further quantitatively analyze the changes in the crystal structure, the sample material was subjected to Rietveld refinement data analysis in this embodiment. The Rietveld refinement diagram is shown in FIG. Figure 6 During the refinement process, GSAS-II software was used to fit the XRD data to the entire spectrum, focusing on extracting indicators such as unit cell parameter a, unit cell volume V, atomic occupancy, and fitting residual, as shown in Tables 2 and 3.

[0115] Table 2 Rietveld refinement data of single S-doped samples

[0116]

[0117]

[0118] Table 3 Rietveld refinement data of EMAL series samples

[0119]

[0120] The analysis results of the changes in the crystal structure of fluorescent materials caused by single and co-doping of aluminum and magnesium ions include:

[0121] 1) In the aluminum ion single doped fluorescent material, the lattice expansion becomes more obvious with the increase of aluminum ion concentration. The unit cell parameter a and volume V of the undoped sample S1 are used as a reference. 3+ In the single doping series, the doping concentrations of S2 and S4 are 1mol% and 4mol%, respectively, and the corresponding unit cell constants are and The volume increases successively, reflecting that Al 3+ Doping causes a slight expansion of the lattice. 3+ The radius is significantly smaller than Y 3+ , its doping should induce lattice contraction, but the actual increase in unit cell parameters indicates that local stress release and structural relaxation effects are dominant.

[0122] 2) In the single-doped magnesium ion fluorescent material, the lattice contraction becomes more obvious with the increase of magnesium ion concentration. 2+ The single-doped samples showed the opposite trend. 2+ The doping concentration increases from 1mol% to 4mol%, and the unit cell parameters increase from Reduce to The volume also shrinks synchronously, indicating that Mg 2+ Replace Y 3+ This change is consistent with the structural compression trend caused by the difference in ionic radius, and no abnormal structural distortion or phase transition was observed, indicating that the doping process is controllable and the structure remains intact.

[0123] 3) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice shrinks slightly when the aluminum ion concentration is low (less than or equal to 0.5 mol%) and the magnesium ion concentration is high (greater than or equal to 3 mol%). 3+ Mg 2+ With Al 3 + The designed doping concentrations of Er are 1mol%, 3mol% and 0.5mol%. The refinement results show that 3+ The total proportion of ions occupying the Y position is 0.01, and they are distributed in two independent positions, Y1 and Y2, with occupancy rates of 0.0004 and 0.0096 respectively; 2+The ions replace the Y1 and Y2 positions with occupancy rates of 0.0012 and 0.0288, respectively, and the total amount is close to the preset value of 3 mol%, indicating that the doping process is well controlled. 3+ The ions are mainly distributed in the Y2 site, with an occupancy rate of 0.005, which is also consistent with the designed concentration. Figure 7 (a) The occupancy of the Y2 position decreased by about 4.3% compared with the full value. This change is related to the 3+ Mg 2+ 、Al 3+ The total substitution ratios of the three doping ions are highly consistent, further verifying the fact that the doping ions successfully enter the lattice to form a stable solid solution. Combined with the unit cell constant of the EMAL-1 sample, it is slightly smaller than that of the undoped sample S1, indicating that under low doping concentration conditions, Mg 2+ The dominant effect causes a slight contraction of the lattice.

[0124] 4) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice expands slightly when the aluminum ion concentration is high (greater than or equal to 4 mol%) and the magnesium ion concentration is low (less than or equal to 0.5 mol%). 3+ 、4mol%Al 3+ and 0.5 mol% Mg 2+ According to the Rietveld refinement results, Er 3+ 、Al 3+ and Mg 2+ All of them have achieved relatively ideal doping concentrations, with total occupancy rates of 0.01, 0.04 and 0.005 respectively, which are basically consistent with the designed values. Figure 7 (b) The unit cell parameter analysis shows that the unit cell constant a of EMAL-2 has slightly expanded compared with the undoped S1 sample. 3+ The ionic radius is much smaller than Y 3+ , its doping should lead to lattice contraction; and Mg 2+ The ionic radius is also smaller than Y 3+ , also has a certain shrinkage effect. But considering the Al in EMAL-2 3+ Higher concentration, Mg 2+ The concentration is low, and the doping ions are distributed in both Y1 and Y2 sites. In particular, the Y2 site occupancy rate decreases from 0.9568 in the S1 sample to 0.9472, indicating that the doping degree of the low-symmetry site has increased significantly, so the local structure has undergone stress relaxation. The local stress release effect offsets part of the shrinkage trend, resulting in a slight expansion of the overall unit cell parameters. Further comparison with the EMAL-1 sample shows that the unit cell constant of EMAL-2 is slightly larger than that of EMAL-1, and the Y2 site occupancy rate is lower, indicating that the high concentration of Al 3+Doping compared to Mg 2+ Doping contributes more significantly to the relaxation of the crystal structure. 3+ The radius of the ion is significantly smaller than that of Y 3+ , tends to cause lattice contraction when doped alone, while Mg 2+ The radius of ions is larger, and it is easier to cause local expansion and structural relaxation after being doped into the lattice. In the EMAL-2 sample, the appropriate amount of Mg 2+ Co-doping leads to the redistribution of local lattice stress, ultimately presenting a slight expansion feature of the overall unit cell parameters, reflecting the synergistic regulatory effect of the two ion doping.

[0125] 5) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the crystal structure is more compact but not distorted when the concentration of aluminum ions (greater than or equal to 4 mol%) and magnesium ions (greater than or equal to 3 mol%) is high. The crystal structure is stable. EMAL-3 is the sample with the highest doping concentration in this group of experiments, containing 1 mol% Er. 3+ 、4mol%Al 3+ With 3 mol% Mg 2+ The Er doping level is still maintained at 0.01, and the Al 3+ With Mg 2+ The occupancy rate of Y2 position is 0.9232, and the substitution ratio is as high as 7.68%, which is the highest among the three groups. It shows that multi-ion co-doping significantly enhances the Y 3+ The occupation situation is as follows Figure 7 (c) As shown. At the structural level, the unit cell parameter a of EMA-L4 is Slightly smaller than EMAL-2 but larger than EMAL-1, showing Al 3+ With Mg 2+ The synergistic effect between 2+ The resulting lattice contraction makes the crystal structure more compact but not distorted. The fitting indicators also show that the structural model of this sample fits best, with the lowest Rwp of 7.16% and Rp of 5.04%, and a χ2 value close to 1, indicating that the structural model of the co-doping system is the best match.

[0126] All samples maintain a cubic crystal structure under the Ia-3 space group, and no secondary phase appears, indicating that the doping process did not destroy the main Y2O3 crystal phase. The fitting residual parameters of each sample are good, with Rwp values ​​between 7.1% and 9.0%, and χ2 close to 1. The fitting quality is high, indicating that the crystal model is accurate and the refinement results are reliable. Among them, the EMAL-3 sample has the highest goodness of fit, indicating that the crystal structure of this sample is the most stable and the model fitting effect is the best. It can be seen that Al 3+ With Mg 2+ The doping of Y2O3:Er3+ The crystal structure of the material, on the contrary, significantly improves the crystal integrity and structural symmetry under reasonable ratio. Especially under co-doping conditions, with the increase of doping concentration, especially Al 3+ As the doping ratio increases, the unit cell parameters rise again, and the unit cell volume also expands. This trend suggests that the local internal stress induced by the initial doping is effectively released under high-doping conditions, leading to a redistribution of lattice energy, which in turn promotes a slight expansion and relaxation of the crystal structure. This change in the local stress field not only alleviates lattice distortion but also may improve the stability of the crystal, contributing to the subsequent improvement of luminescence performance.

[0127] 8. Optimal Ratio Analysis

[0128] In this embodiment, aluminum ions and magnesium ions co-doped yttrium oxide doped erbium fluorescent materials (Y2O3:Er 3+ / Al 3+ / Mg 2+ ) to analyze the doping ratio of aluminum ions and magnesium ions.

[0129] Among them, EMAL-3 in Table 1 is the optimal ratio of various components when preparing yttrium-doped erbium-doped fluorescent materials co-doped with aluminum ions and magnesium ions (see Case 4 in Table 4). This optimal ratio can best balance the up-conversion luminescence efficiency and crystal structure stability of the fluorescent material, and the fluorescence lifetime can meet actual requirements.

[0130] In other preferred embodiments, aluminum ion and magnesium ion co-doped yttrium oxide-doped erbium fluorescent materials can also be prepared using the composition ratios of other cases in Table 4. However, compared with Case 4, the upconversion luminescence efficiency and lifespan of Case 1 are significantly reduced, but the crystal structure stability is better; the upconversion luminescence efficiency of Case 2 is comparable to that of Case 4, but the lifespan is significantly reduced, and the lattice shrinks significantly, that is, the crystal structure stability is poor; the upconversion luminescence efficiency of Case 3 is comparable to that of Case 4, and the lifespan is significantly increased, but the lattice expands significantly, that is, the crystal structure stability is poor; the upconversion luminescence efficiency of Case 5 is comparable to that of Case 4, but the service life is significantly reduced. The reason for this is that excessive aluminum ion and magnesium ion concentrations have a significant impact on the lifespan of the fluorescent material. Therefore, only Case 4 can achieve excellent upconversion luminescence efficiency, lifespan, and crystal structure stability for the fluorescent material.

[0131] Table 4

[0132]

[0133] In summary, aluminum ions (Al 3+ ) concentration range is: 0.5mol%-4mol%; magnesium ions (Mg 2+ ) concentration range is: 0.5mol%-3mol%.

[0134] Among them, the optimal concentration of aluminum ions and magnesium ions co-doped yttrium oxide erbium-doped fluorescent material is: 4 mol% Al 3+ 、3mol%Mg 2+ 、1mol%Er 3+ 、92mol%Y 3+ .

[0135] Example 2:

[0136] This embodiment discloses an aluminum ion and magnesium ion co-doped yttrium oxide doped erbium fluorescent material, which is prepared based on the experimental analysis results of the experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent material in Example 1.

[0137] The method for preparing the yttrium oxide-doped erbium fluorescent material co-doped with aluminum ions and magnesium ions comprises:

[0138] 1) Obtaining erbium nitrate hexahydrate (Er(NO3)3·6H2O), yttrium nitrate hexahydrate (Y(NO3)3·6H2O), aluminum acetate dihydrate (C6H9AlO6·2H2O) and magnesium acetate tetrahydrate (C4H6MgO4·4H2O) for preparing a fluorescent material;

[0139] 2) dissolving erbium nitrate hexahydrate, yttrium nitrate hexahydrate, aluminum acetate dihydrate, and magnesium acetate tetrahydrate in deionized water to obtain a mixed solution;

[0140] 3) adding citric acid to the mixed solution to adjust the pH value of the mixed solution to obtain a precursor solution;

[0141] 4) Stirring the precursor solution at a constant temperature of a preset temperature to form a (yellow-brown) precursor;

[0142] 5) Spread the precursor (evenly) (on an optical platform) and then anneal it with a laser to obtain aluminum ions (Al 3+ ) and magnesium ions (Mg 2+ ) co-doped yttrium oxide doped erbium (Y2O3:Er 3+ ) fluorescent material (Y2O3:Er 3+ / Al 3+ / Mg 2+ ).

[0143] The present invention designs aluminum ions (Al 3+ ) and magnesium ions (Mg 2+ ) co-doped Y2O3:Er 3+ The preparation process of fluorescent materials can significantly improve the fluorescence performance of rare earth luminescent materials, and provide a technical reference for the design and development of high-efficiency fluorescent materials. The optimized co-doped fluorescent materials (Y2O3:Er 3+ / Al3+ / Mg 2+ ) has higher luminous efficiency and better thermal stability, and has a wide range of practical application potential. First, by doping Al 3+ Ions can effectively repair crystal defect sites and reduce non-radiative transition paths; while doping with Mg 2+ Ions can optimize the energy transfer process by inducing local crystal field compression effects, significantly improving luminescence efficiency and lifetime. 3+ and Mg 2+ Co-doping, in the play of single doping Al 3+ and Mg 2+ Based on their respective advantages, the comprehensive luminescence enhancement of fluorescent materials is achieved, in which the green and red emission intensities of the fluorescent materials reach 3+ and Mg 2 + Several times of that, which can significantly improve the up-conversion luminescence efficiency of fluorescent materials. 3+ Doping can alleviate the Mg 2+ The tendency of shortening the excited state lifetime brought about by doping ensures the life of the fluorescent material.

[0144] In a specific implementation process, the aluminum ions and magnesium ions are co-doped into the yttrium-doped erbium oxide fluorescent material:

[0145] Aluminum ions (Al 3+ ) concentration range is: 0.5mol%-4mol%;

[0146] Magnesium ion (Mg 2+ ) concentration range is: 0.5mol%-3mol%;

[0147] Erbium ions (Er 3+ ) concentration range is: 0.5mol%-1.5mol%;

[0148] Yttrium ion (Y 3+ ) concentration range is: 90mol%-94mol%.

[0149] Among them, the optimal concentration of aluminum ions and magnesium ions co-doped yttrium oxide erbium-doped fluorescent material is: 4 mol% Al 3+ 、3mol%Mg 2+ 、1mol%Er 3+ 、92mol%Y 3+ .

[0150] It was found through experiments that 4 mol% Al 3+ 、3mol%Mg 2+ 、1mol%Er 3+ 、92mol%Y3+ Y2O3:Er at different concentrations 3 + / Al 3+ / Mg 2+ It has the best up-conversion luminescence efficiency.

[0151] During the specific implementation process, the amount of citric acid added is calculated based on the principle that the molar ratio of cations to citric acid in the mixed solution is 1:2. The present invention adds citric acid at a molar ratio of cations to citric acid of 1:2, so that citric acid and cations form a stable complex, effectively preventing the hydrolysis and precipitation of metal ions, making the solution uniform and stable, and facilitating subsequent gel formation. At the same time, the complexation can control the release rate of metal ions, making crystal growth more uniform and reducing defects during laser annealing. In addition, citric acid, as a chelating agent and carbon source, decomposes and produces gas during heat treatment, which can increase the porosity of the material, improve fluorescence properties, and enhance luminous efficiency.

[0152] During the specific implementation process, the pH value of the mixed solution is adjusted to 7 using ammonium hydroxide. By adjusting the pH value of the mixed solution to a neutral environment of 7, side reactions such as hydrolysis and precipitation of metal cations can be avoided, ensuring solution stability and allowing for uniform sol formation. At the same time, neutral conditions can reduce the introduction of impurities and reduce the impact on the purity of the fluorescent material. In addition, during the laser annealing stage, the stable sol structure facilitates uniform crystal growth, thereby improving the luminescence performance of the fluorescent material and enhancing the luminescence intensity and stability.

[0153] During the specific implementation process, the precursor solution is stirred at a constant temperature of 150°C until a stable precursor is formed. The high temperature of 150°C accelerates chemical reactions between the precursors, promoting sol formation and gelation, and shortening the preparation cycle. Stirring ensures uniform heating of the solution, allowing the components to fully mix and react, avoiding localized concentration variations and ensuring a uniform precursor structure and composition. During laser annealing, the stable precursor is more evenly converted into the target fluorescent material, reducing crystal defects.

[0154] During the specific implementation process, a 980nm infrared laser is used to irradiate the precursor for annealing, resulting in an aluminum- and magnesium-ion co-doped yttrium oxide-doped erbium fluorescent material. The 980nm infrared laser has high energy density and precise focusing, enabling rapid, localized heating of the precursor, shortening the annealing time and improving preparation efficiency. Furthermore, laser annealing can stimulate electron transitions within the material, optimize the crystal structure, and reduce the density of defect states, thereby enhancing the luminous efficiency and intensity of the fluorescent material.

[0155] Specifically, the laser power is set to 15W and the spot area is set to 9mm. 2, irradiate until the color of the precursor changes from brown (gradually) to white. After reaching the first preset time (about 10 seconds), the power of the laser is increased to 19W, and the spot diameter is reduced to about 3mm. Continue irradiation until the precursor is completely melted and fused into a dense crystal structure, thus obtaining aluminum ion and magnesium ion co-doped yttrium oxide erbium-doped fluorescent material.

[0156] In this embodiment, the total laser heating time is optimized to 30 seconds to ensure that high-quality fluorescent materials are obtained.

[0157] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the technical solutions. Those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present invention that do not depart from the purpose and scope of the technical solutions of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An experimental analysis method for aluminum ion and magnesium ion co-doped fluorescent materials, characterized in that: include: S1: preparing undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials; S2: Analyze the fluorescence intensity of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the luminescence intensity of fluorescent materials; S3: Analyze the fluorescence lifetime of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the effects of aluminum ion and magnesium ion single-doping and co-doping on the lifetime of fluorescent materials; S4: Analyze the crystal structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the microscopic regulation effect of aluminum ion and magnesium ion single-doping and co-doping on the lattice structure of fluorescent materials; S5: Analyze the Rietveld refined structures of undoped fluorescent materials, aluminum ion single-doped fluorescent materials, magnesium ion single-doped fluorescent materials, and aluminum ion and magnesium ion co-doped fluorescent materials, and obtain the analysis results of the changes in the crystal structure of fluorescent materials caused by aluminum ion and magnesium ion single-doping and co-doping; S6: Based on the analysis of the effects of single and co-doping of aluminum and magnesium ions on the luminescence intensity, lifetime, microscopic regulation of crystal structure, and changes in crystal structure of fluorescent materials, the advantages of co-doping of aluminum and magnesium ions over no doping and single doping of aluminum and magnesium ions are analyzed; S7: Based on the requirements of fluorescent materials, combined with the analysis results of the advantages of co-doping with aluminum ions and magnesium ions over no doping and single doping with aluminum ions and magnesium ions, a doping scheme of aluminum ions and magnesium ions is selected, and the corresponding fluorescent materials are prepared.

2. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 1, characterized in that: In step S2, the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity of the fluorescent material include: 1) Compared with undoped fluorescent materials, aluminum ion-doped fluorescent materials have higher luminescence intensity; aluminum ions enhance the green light emission intensity of the fluorescent materials; 2) Compared with undoped fluorescent materials, magnesium ions alone doped fluorescent materials have improved luminescence intensity; magnesium ions enhance the red light emission intensity of the fluorescent material; 3) The green light emission intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is several times that of the fluorescent material doped with aluminum ions alone; 4) The red light emission intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is several times that of the fluorescent material doped with magnesium ions alone.

3. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 2, characterized in that: In step S6, the advantages determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the luminous intensity of the fluorescent material are: the luminous intensity of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the undoped fluorescent material and the fluorescent material single-doped with aluminum ions and magnesium ions, that is, the co-doping of aluminum ions and magnesium ions improves the up-conversion luminous efficiency of the fluorescent material compared with the undoped fluorescent material and the single doping with aluminum ions and magnesium ions.

4. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 1, characterized in that: In step S3, the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the life of the fluorescent material are as follows: 1) Compared with undoped fluorescent materials, aluminum ion single-doped fluorescent materials extend the excited state lifetime; 2) Compared with undoped fluorescent materials, single-magnesium ion doped fluorescent materials have shorter excited state lifetimes; 3) The lifetime of the aluminum ion and magnesium ion co-doped fluorescent material is shorter than the excited state lifetime of the aluminum ion single doped fluorescent material and the undoped fluorescent material, and is longer than the excited state lifetime of the magnesium ion single doped fluorescent material.

5. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 1, characterized in that: In step S6, the advantages determined based on the analysis results of the effects of single doping and co-doping of aluminum ions and magnesium ions on the lifespan of the fluorescent material are: the lifespan of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent material doped with magnesium ions alone, that is, the co-doping of aluminum ions and magnesium ions alleviates the trend of shortening of the excited state lifetime caused by magnesium ion doping through the introduction of aluminum ions.

6. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 1, characterized in that: In step S4, the analysis results of the microscopic control effects of single doping and co-doping of aluminum ions and magnesium ions on the lattice structure of the fluorescent material include: 1) Compared with undoped fluorescent materials, the diffraction peak of aluminum ion-doped fluorescent materials shifts toward low angles and the interplanar spacing increases, i.e., the lattice expands. 2) Compared with the undoped fluorescent material, the main diffraction peak of the magnesium ion single-doped fluorescent material shifts to the high-angle direction, and the interplanar spacing becomes smaller, that is, the lattice shrinks; 3) Compared with the undoped fluorescent material, the overall distribution of the main diffraction peak of the aluminum ion and magnesium ion co-doped fluorescent material does not change, and the crystal structure is stable.

7. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 6, characterized in that: In step S6, the advantages determined based on the analysis results of the microscopic regulatory effects of single doping and co-doping of aluminum ions and magnesium ions on the lattice structure of the fluorescent material are: the crystal structure of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent material single doped with aluminum ions and the fluorescent material single doped with magnesium ions, that is, the co-doping of aluminum ions and magnesium ions improves the crystal structure stability of the fluorescent material compared with the undoped fluorescent material and the single doping of aluminum ions and magnesium ions.

8. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 1, characterized in that: In step S5, the analysis results of the changes in the crystal structure of the fluorescent material caused by single doping and co-doping of aluminum ions and magnesium ions include: 1) In aluminum ion-doped fluorescent materials, the lattice expansion becomes more obvious with the increase of aluminum ion concentration; 2) In the magnesium ion single-doped fluorescent material, the lattice contraction becomes more obvious with the increase of magnesium ion concentration; 3) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice shrinks when the aluminum ion concentration is low and the magnesium ion concentration is high; 4) In the case of aluminum ion and magnesium ion co-doped fluorescent materials, the lattice expands when the concentration of aluminum ions is high and the concentration of magnesium ions is low; 5) In the fluorescent material co-doped with aluminum ions and magnesium ions, the crystal structure is stable in the case of high concentrations of aluminum ions and high concentrations of magnesium ions.

9. The experimental analysis method of aluminum ion and magnesium ion co-doped fluorescent material according to claim 8, characterized in that: In step S6, based on the analysis results of the changes in the crystal structure of the fluorescent material by single doping and co-doping of aluminum ions and magnesium ions, the advantage is determined as follows: the crystal structure of the fluorescent material co-doped with aluminum ions and magnesium ions is better than that of the fluorescent materials single doped with aluminum ions and magnesium ions.

10. A fluorescent material co-doped with aluminum ions and magnesium ions, characterized in that: The method is prepared based on the experimental analysis results of the experimental analysis method of the aluminum ion and magnesium ion co-doped fluorescent material in claim 1.

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