A metal halide dual-mode luminescent material and its rapid microwave synthesis method

Abstract

This invention provides a metal halide dual-mode luminescent material and its rapid microwave synthesis method, belonging to the field of luminescent material technology. Through precise ion doping design and controllable synthesis process, the metal halide dual-mode luminescent material of this invention achieves excellent luminescent performance, integrating up-conversion and down-conversion luminescence capabilities in the same system. It can be used in fields such as multi-mode optical anti-counterfeiting, information encryption, and integrated bio-imaging and diagnosis. The rapid microwave synthesis method is efficient and controllable, avoiding component volatilization and lattice defects caused by high-temperature and long-term processing. It achieves atomic-level uniform doping, has good process repeatability, is suitable for large-scale preparation, and meets the requirements of green synthesis and low-cost manufacturing.

Description

Technical Field

[0001] This invention belongs to the field of luminescent materials technology, specifically relating to a metal halide dual-mode luminescent material and its rapid microwave synthesis method. Background Technology

[0002] Perovskite-structured metal halide luminescent materials, with their tunable band gaps, high photoluminescence quantum yields, and excellent charge transport properties, have shown great application potential in fields such as light-emitting diodes, lasers, radiation detection, and bioimaging and display technologies. Among them, double perovskite halides (such as Cs₂NaYbCl₆) have become important matrix materials for achieving efficient luminescence, especially upconversion luminescence, due to their unique crystal structure, excellent structural stability, and abundant rare-earth ion energy levels. By introducing specific activating ions into these matrices, efficient energy transfer systems can be constructed, thereby obtaining multi-mode luminescence characteristics and expanding their applications in cutting-edge fields such as information encryption, multi-dimensional display, and integrated biomedical diagnosis. However, the full realization of the performance of double perovskite halide materials and their practical application transformation are fundamentally limited by efficient, controllable, and scalable synthesis processes.

[0003] Currently, the main methods for preparing double perovskite halide materials include high-temperature solid-state methods and conventional liquid-phase methods. High-temperature solid-state methods typically require prolonged calcination of the reaction precursor at high temperatures (≥600℃) under an inert atmosphere. This process is not only energy-intensive and time-consuming, but also prone to a series of adverse problems. For example, halogen components are easily volatilized at high temperatures, leading to deviations in the matrix stoichiometry, the generation of numerous vacancy defects, an increase in non-radiative recombination centers, and severe quenching of luminescence. Furthermore, prolonged high-temperature heat treatment can promote excessive grain growth and coarsening, reducing the specific surface area and making it difficult to achieve uniform distribution of dopant ions, thus affecting energy transfer efficiency. Moreover, the process repeatability is extremely sensitive to temperature profiles and atmosphere control, resulting in poor batch stability and making it difficult to meet the needs of large-scale, standardized production.

[0004] To lower the reaction temperature, many researchers have begun to explore liquid-phase synthesis methods such as solvothermal and hot-injection methods. While these methods have alleviated the problem of component volatilization caused by high temperatures to some extent, they still have many limitations: the reaction cycle usually still takes several to tens of hours, resulting in low efficiency; the process often involves multiple steps of mixing, separation, washing, and drying, which are cumbersome and have limited yields; the use of large amounts of organic solvents not only increases costs but also brings safety and environmental post-treatment burdens; more importantly, under conventional liquid-phase heating modes, the non-uniformity of heat conduction makes it difficult to achieve precise and uniform control of the incorporation and distribution of dopant ions in the crystal lattice, easily forming concentration gradients or local phase separation, which cannot guarantee the optimization of the distance between energy donor and acceptor ions, thus limiting the maximization of energy transfer efficiency and ultimately affecting the luminescence intensity and stability of the material.

[0005] In summary, the contradiction of the existing synthesis technology lies in that if the crystal quality and thermodynamic stability are pursued, the cost of out-of-control components, uneven doping and high energy consumption brought by the high-temperature solid-phase method need to be borne; if mild reaction conditions are pursued, challenges such as long cycle, poor uniformity and complex process existing in the liquid-phase method need to be faced. This contradiction has led to great difficulties in the controllable preparation of high-performance, especially dual-mode luminescent materials relying on efficient energy transfer of multiple ions. Therefore, developing a new preparation method that can achieve rapid and uniform synthesis under mild conditions, ensure atomic-level dispersion of doped ions, and has the characteristics of simple process, low energy consumption and easy amplification has become the key technical problem for the industrial application of perovskite metal halide luminescent materials. Summary of the Invention

[0006] To overcome the above-mentioned shortcomings and deficiencies of the existing technology, the present application first provides a metal halide dual-mode luminescent material.

[0007] Furthermore, the chemical general formula of the metal halide dual-mode luminescent material is: Cs2NaYb 1-x-y Bi x Mn y Cl6, where x is 0 < x < 0.5 and y is 0 < y < 0.5.

[0008] Preferably, in the chemical general formula: 0.02 ≤ x <0.4, 0.02 ≤ y <0.4.

[0009] Preferably, in the chemical general formula: 0.05 ≤ x <0.3, 0.05 ≤ y <0.3.

[0010] Secondly, the present application provides a rapid microwave synthesis method for a metal halide dual-mode luminescent material, including the following steps:

[0011] S1. Mix the raw materials of Cs, Na, Yb, Bi, and Mn elements with hydrochloric acid solution evenly to form a precursor solution; S2. Place the precursor solution in a microwave reactor and reflux for 1 - 60 min at a power of 300 - 800 W to obtain a reaction suspension; S3. Cool the suspension, and after solid-liquid separation, washing, and drying, obtain the metal halide dual-mode luminescent material.

[0012] Furthermore, the raw materials of Cs, Na, Yb, Bi, and Mn elements are independently selected from at least one of their chlorides, oxides, nitrates, acetates, oxalates, and sulfates.

[0013] Preferably, the raw materials for the Cs, Na, Yb, Bi, and Mn elements are selected from their chlorides.

[0014] Furthermore, the volume ratio of concentrated hydrochloric acid to deionized water in the hydrochloric acid solution is 1:0-10, preferably 1:1-5.

[0015] Furthermore, the product Cs2NaYb in the precursor solution is set to... 1-x-y Bi x Mn y The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 1-30 mL, preferably 1 mmol: 5-10 mL.

[0016] Furthermore, the reflux reaction time is 5-30 minutes.

[0017] Furthermore, the solvent used in the washing process of S3 is at least one of ketone solvents and alcohol solvents, preferably an alcohol solvent; the ketone solvents include, but are not limited to, at least one of acetone and butanone; the alcohol solvents are selected from at least one of methanol, ethanol, isopropanol, n-propanol, and isobutanol.

[0018] Furthermore, during the drying process of S3, the drying temperature is 60-120℃ and the drying time is 1-12h.

[0019] Preferably, the drying temperature is 80-100℃ and the drying time is 3-6 hours.

[0020] The beneficial effects of this invention are: Compared with the prior art, the beneficial effects provided by this invention are significantly reflected in many aspects such as synthesis method, material properties, and application potential: (1) The metal halide dual-mode luminescent material designed in this invention exhibits excellent luminescent performance, achieved through Bi 3+ To Mn 2+ The material exhibits strong yellow-green downconversion luminescence under ultraviolet light excitation due to its high-efficiency energy transfer; with the help of Yb 3+ Sensitization and Mn 2+ Energy transfer enables green upconversion luminescence under near-infrared light excitation; this dual-mode luminescence characteristic stems from meticulous ion doping design and controllable synthesis process.

[0021] (2) The metal halide dual-mode luminescent material designed in this invention integrates up-conversion and down-conversion luminescence capabilities in the same system, and can be used in fields such as multi-mode optical anti-counterfeiting, information encryption, bio-imaging and integrated diagnosis and treatment, thus expanding the functional application boundaries of perovskite metal halide luminescent materials.

[0022] (3) The preparation method used in this invention is highly efficient and controllable; by selecting microwave liquid phase reflux technology, the rapidity and uniformity of microwave heating are utilized to significantly shorten the reaction time to within tens of minutes, avoiding component volatilization and lattice defects caused by long-term high-temperature treatment, while simultaneously achieving Bi 3+ and Mn 2+ In Cs2NaYbCl6Bi 3+ The matrix exhibits atomically uniform doping, resulting in good process repeatability and suitability for large-scale preparation.

[0023] (4) The entire preparation process of this invention does not require inert atmosphere protection or high temperature calcination, uses less solvent, consumes less energy, and has simple post-processing, which meets the requirements of green synthesis and low-cost manufacturing. Attached Figure Description

[0024] Figure 1 Cs2NaYb prepared in Example 1 of this invention 0.7 Bi 0.1 Mn 0.2 X-ray powder diffraction pattern of Cl6 luminescent material.

[0025] Figure 2 Cs2NaYb prepared in Example 2 of this invention 0.7 Bi 0.15 Mn 0.15 Room temperature emission spectrum of Cl6 luminescent material under 360 nm light excitation.

[0026] Figure 3 Cs2NaYb prepared in Example 2 of this invention 0.7 Bi 0.15 Mn 0.15 The room-temperature emission spectrum of Cl6 luminescent material under 980nm light excitation.

[0027] Figure 4 The Cs2NaYb prepared in Example 3 of this invention 0.4 Bi 0.3 Mn 0.3 SEM image of Cl6 luminescent material.

[0028] Figure 5 The Cs2NaYb prepared in Comparative Example 1 of this invention 0.7 Bi 0.1 Mn 0.2 X-ray powder diffraction pattern of Cl6 luminescent material.

[0029] Figure 6 Comparative Example 2 of this invention prepared Cs2NaYb 0.1 Bi 0.15 Mn 0.75Room-temperature emission spectra of Cl6 samples under photoexcitation at 360 nm and 980 nm respectively.

[0030] Figure 7 : Cs2NaYb prepared in Comparative Example 3 of the present invention 0.7 Bi 0.1 Mn 0.2 X-ray powder diffraction pattern of Cl6. Detailed implementation manners

[0031] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

[0032] This application first provides a metal halide dual-mode luminescent material, and the chemical general formula of the metal halide dual-mode luminescent material is: Cs2NaYb 1-x-y Bi x Mn y Cl6, where x is 0 < x < 0.5, y is 0 < y < 0.5, x is the molar fraction of Bi 3+ ions substituting for Yb 3+ ions, and y is the molar fraction of Mn 2+ ions substituting for Yb 3+ ions.

[0033] Preferably, in the chemical general formula: 0.02 ≤ x < 0.4, 0.02 ≤ y < 0.4.

[0034] Furthermore, by way of example but not limitation, x and y are independently any one of 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.4, etc.

[0035] In one implementation manner, x is 0.08 and y is 0.02.

[0036] In one implementation manner, x is 0.1 and y is 0.05.

[0037] In one implementation, x is 0.15 and y is 0.15.

[0038] In one implementation, x is 0.1 and y is 0.2.

[0039] In one implementation, x is 0.3 and y is 0.3.

[0040] Preferably, in the general chemical formula: 0.05 ≤ x <0.3, 0.05≤ y <0.3.

[0041] Secondly, this application provides a rapid microwave synthesis method for metal halide dual-mode luminescent materials, comprising the following steps: S1. Take the raw materials containing Cs, Na, Yb, Bi, and Mn elements and mix them evenly with hydrochloric acid solution to form a precursor solution; S2. Place the precursor solution in a microwave reactor and reflux it at a power of 300-800W for 1-60 minutes to obtain a reaction suspension. S3. The suspension is cooled, and after solid-liquid separation, washing, and drying, the metal halide dual-mode luminescent material is obtained.

[0042] Furthermore, the raw materials for Cs, Na, Yb, Bi, and Mn elements are independently selected from at least one of their chlorides, oxides, nitrates, acetates, oxalates, and sulfates. For example, but not limitingly, the raw material for Cs element is selected from at least one of cesium chloride (CsCl), cesium oxide (Cs₂O), cesium nitrate (CsNO₃), cesium acetate (CH₃COOCs), cesium oxalate (Cs₂C₂O₄), and cesium sulfate (Cs₂SO₄). For example, but not limited, the raw material for Na is selected from at least one of sodium chloride (NaCl), sodium oxide (Na2O), sodium peroxide (Na2O2), sodium nitrate (NaNO3), sodium acetate (CH3COONa), sodium oxalate (Na2C2O4), sodium sulfate (Na2SO4), and sodium bisulfate (NaHSO4); for example, but not limited, the raw material for Yb is selected from at least one of ytterbium chloride (YbCl3), ytterbium oxide (Yb2O3), ytterbium nitrate (Yb(NO3)3), ytterbium acetate (Yb(CH3COO)3), ytterbium oxalate (Yb2(C2O4)3), and ytterbium sulfate (Yb2(SO4)3); for example, but not limited, the raw material for Bi is selected from at least one of bismuth trichloride (BiCl3), bismuth oxide (Bi2O3), bismuth nitrate (Bi(NO3)3), and bismuth acetate (Bi... (CH3COO)3), bismuth oxalate (Bi2(C2O4)3), and bismuth sulfate (Bi2(SO4)3); the raw material for Mn element, by way of example but not limitation, is selected from at least one of manganese dichloride (MnCl2), manganese oxide (MnO), manganese nitrate (Mn(NO3)2), manganese acetate (Mn(CH3COO)2), manganese oxalate (MnC2O4), and manganese sulfate (MnSO4); this application does not make any requirements on the form of the above raw materials, which may be pure compounds (including analytical grade, chemically pure, spectroscopically pure, chromatographically pure, etc.) or hydrates of compounds.

[0043] Preferably, the raw materials for the Cs, Na, Yb, Bi, and Mn elements are selected from their chlorides.

[0044] Furthermore, the volume ratio of concentrated hydrochloric acid to deionized water in the hydrochloric acid solution is 1:0-10, preferably 1:1-5.

[0045] Furthermore, the product Cs2NaYb in the precursor solution is set to... 1-x-y Bi x Mn y The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 1-30 mL, preferably 1 mmol: 5-10 mL.

[0046] Furthermore, an example, but not a limiting one, of the product Cs2NaYb 1-x-y Bi x Mny The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is any one of the following: 1 mmol: 2 mL, 1 mmol: 4 mL, 1 mmol: 5 mL, 1 mmol: 6 mL, 1 mmol: 7 mL, 1 mmol: 8 mL, 1 mmol: 9 mL, 1 mmol: 10 mL, 1 mmol: 13 mL, 1 mmol: 15 mL, 1 mmol: 20 mL, 1 mmol: 24 mL, 1 mmol: 25 mL, 1 mmol: 27 mL, 1 mmol: 30 mL.

[0047] Furthermore, the microwave power is selected from any one of 300W, 330W, 350W, 380W, 400W, 420W, 450W, 470W, 490W, 500W, 510W, 530W, 550W, 580W, 600W, 620W, 650W, 670W, 690W, 700W, 710W, 740W, 750W, 780W, 800W, etc.

[0048] Furthermore, the reflux reaction time is 5-30 minutes.

[0049] Furthermore, the solvent used in the washing process of S3 is at least one of ketone solvents and alcohol solvents, preferably an alcohol solvent; the ketone solvents include, but are not limited to, at least one of acetone and butanone; the alcohol solvents are selected from at least one of methanol, ethanol, isopropanol, n-propanol, and isobutanol.

[0050] In one embodiment, the solvent used in the washing process of S3 is ethanol with a mass concentration of 90-99%.

[0051] Furthermore, during the drying process of S3, the drying temperature is 60-120℃ and the drying time is 1-12h.

[0052] Preferably, the drying temperature is 80-100℃ and the drying time is 3-6 hours.

[0053] Example 1 This embodiment provides a metal halide dual-mode luminescent material with the general chemical formula: Cs₂NaYb 0.7 Bi 0.10 Mn 0.20 Cl6.

[0054] The rapid microwave synthesis method for the metal halide dual-mode luminescent material includes the following steps: S1. Weigh out cesium chloride (CsCl), sodium chloride (NaCl), ytterbium chloride (YbCl3·6H2O), bismuth chloride (BiCl3), and manganese sulfate (MnSO4·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water in a 1:2 volume ratio. The target product is Cs2NaYb. 0.7 Bi 0.10 Mn 0.20 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 8 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0055] S2. Place the precursor solution in a microwave reactor and reflux it at 800W for 10 minutes. After the reaction is complete, allow the system to cool naturally to room temperature to obtain a suspension containing a white precipitate. S3. Cool the suspension, centrifuge, discard the supernatant, and wash the resulting solid precipitate three times with anhydrous ethanol, centrifuging after each wash. Finally, place the washed precipitate in a forced-air drying oven and dry at 90℃ for 4 hours. After grinding, the final metal halide dual-mode luminescent material is obtained. Its X-ray powder diffraction pattern is shown in the appendix. Figure 1 .

[0056] Example 2 This embodiment provides a metal halide dual-mode luminescent material with the general chemical formula: Cs₂NaYb 0.7 Bi 0.15 Mn 0.15 Cl6.

[0057] The rapid microwave synthesis method for the metal halide dual-mode luminescent material includes the following steps: S1. Weigh out cesium chloride (CsCl), sodium chloride (NaCl), ytterbium chloride (YbCl3·6H2O), bismuth chloride (BiCl3), and manganese sulfate (MnSO4·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water in a 1:1 volume ratio. The target product is Cs2NaYb. 0.7 Bi 0.15 Mn 0.15 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 6 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0058] S2. Place the precursor solution in a microwave reactor and reflux it at 600W for 15 minutes. After the reaction is complete, allow the system to cool naturally to room temperature to obtain a suspension containing a white precipitate. S3. Cool the suspension, centrifuge, discard the supernatant, and wash the resulting solid precipitate four times with 95wt% ethanol, centrifuging after each wash. Finally, place the washed precipitate in a forced-air drying oven and dry at 80℃ for 6 hours. After grinding, the final metal halide dual-mode luminescent material is obtained. Its room-temperature emission spectrum is shown in the appendix. Figure 2-3 .

[0059] Example 3 This embodiment provides a metal halide dual-mode luminescent material with the general chemical formula: Cs₂NaYb 0.4 Bi 0.3 Mn 0.3 Cl6.

[0060] The rapid microwave synthesis method for the metal halide dual-mode luminescent material includes the following steps: S1. Weigh cesium nitrate (CsNO3), sodium acetate (CH3COONa), ytterbium oxide (Yb2O3, pre-dissolved in a small amount of hydrochloric acid), bismuth nitrate (Bi(NO3)3·5H2O), and manganese acetate (Mn(CH3COO)2·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water in a volume ratio of 1:4. The target product is Cs2NaYb. 0.4 Bi 0.3 Mn 0.3 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 10 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0061] S2. Place the precursor solution in a microwave reactor and reflux it at 700W for 25 minutes. After the reaction is complete, allow the system to cool naturally to room temperature to obtain a suspension containing a white precipitate. S3. Cool the suspension, centrifuge, discard the supernatant, and wash the resulting solid precipitate twice with isopropanol and once with acetone, centrifuging after each wash. Finally, place the washed precipitate in a drying oven and dry at 100℃ for 3 hours. After grinding, the final metal halide dual-mode luminescent material is obtained. Its SEM image is attached. Figure 4 .

[0062] Example 4 This embodiment provides a metal halide dual-mode luminescent material with the general chemical formula: Cs₂NaYb 0.9 Bi 0.08 Mn 0.02 Cl6.

[0063] The rapid microwave synthesis method for the metal halide dual-mode luminescent material includes the following steps: S1. Weigh out cesium chloride (CsCl), sodium chloride (NaCl), ytterbium chloride (YbCl3·6H2O), bismuth chloride (BiCl3), and manganese sulfate (MnSO4·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water at a volume ratio of 1:0.5. Develop the product Cs2NaYb according to the target product. 0.9 Bi 0.08 Mn 0.02 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 5 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0064] S2. Place the precursor solution in a microwave reactor and reflux it at 800W for 3 minutes. After the reaction is complete, allow the system to cool naturally to room temperature to obtain a suspension containing a white precipitate. S3. Cool the suspension, centrifuge to separate it, discard the supernatant, and wash the resulting solid precipitate three times with anhydrous ethanol, centrifuging after each wash. Finally, place the washed precipitate in a forced-air drying oven and dry it at 60°C for 12 hours. After grinding, the final metal halide dual-mode luminescent material is obtained.

[0065] Example 5 This embodiment provides a metal halide dual-mode luminescent material with the general chemical formula: Cs₂NaYb 0.85 Bi 0.1 Mn 0.05 Cl6.

[0066] The rapid microwave synthesis method for the metal halide dual-mode luminescent material includes the following steps: S1. Weigh out cesium chloride (CsCl), sodium chloride (NaCl), ytterbium chloride (YbCl3·6H2O), bismuth chloride (BiCl3), and manganese sulfate (MnSO4·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water at a volume ratio of 1:10. Develop the product Cs2NaYb according to the target product. 0.85Bi 0.1 Mn 0.05 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 30 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0067] S2. Place the precursor solution in a microwave reactor and microwave reflux at 300W for 60 min; after the reaction is complete, allow the system to cool naturally to room temperature to obtain a suspension. S3. Cool the suspension, centrifuge, discard the supernatant, and wash the resulting solid precipitate once with 95wt% ethanol. Finally, place the washed precipitate in a forced-air drying oven and dry it at 120℃ for 1 hour.

[0068] Comparative Example 1 The difference between this comparative example and Example 1 is that the preparation method of the metal halide dual-mode luminescent material adopts a hydrothermal method, specifically: S1. Weigh out cesium chloride (CsCl), sodium chloride (NaCl), ytterbium chloride (YbCl3·6H2O), bismuth chloride (BiCl3), and manganese sulfate (MnSO4·4H2O) as raw materials for each metal element, ensuring that the molar ratio of each metal element strictly conforms to the stoichiometric ratio in the general chemical formula. Mix the above raw materials in a round-bottom flask. Prepare a hydrochloric acid solution by mixing concentrated hydrochloric acid and deionized water in a 1:2 volume ratio. The target product is Cs2NaYb. 0.7 Bi 0.10 Mn 0.20 The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 8 mL. The hydrochloric acid solution is added to a round-bottom flask and mixed with the raw materials of each metal element. The mixture is then magnetically stirred until a homogeneous and clear precursor solution is formed.

[0069] S2. Place the precursor solution in a reaction vessel and hydrothermally react at 150°C for 10 hours to obtain a reaction mixture. S3. Cool the reaction mixture, centrifuge, discard the supernatant, and wash the resulting solid precipitate three times with anhydrous ethanol, centrifuging after each wash. Finally, place the washed precipitate in a forced-air drying oven and dry at 90℃ for 4 hours. After grinding, the final metal halide dual-mode luminescent material is obtained. Its X-ray powder diffraction pattern is shown in the appendix. Figure 5 .

[0070] Comparative Example 2 This comparative example provides a metal halide luminescent material with the general chemical formula Cs₂NaYb. 0.1 Bi 0.15 Mn 0.75Cl6 was prepared using the same method as in Example 2. The room-temperature emission spectra of the metal halide luminescent material from Comparative Example 2 under excitation at 360 nm and 980 nm are shown in the appendix. Figure 6 .

[0071] Comparative Example 3 The difference between this comparative example and Example 1 is that the sample was prepared using a microwave power of 200 W. The X-ray powder diffraction pattern of the metal halide luminescent material prepared in Comparative Example 3 is attached. Figure 7 .

[0072] Results analysis: Appendix Figure 1 Cs2NaYb of Example 1 0.7 Bi 0.10 Mn 0.20 X-ray powder diffraction pattern of Cl6 luminescent material (with attached) Figure 5 The X-ray powder diffraction pattern of the luminescent material in Comparative Example 1 is shown in the attached diagram. Figure 1 and attached Figure 5 It can be seen that the appendix Figure 5 The intensity of each diffraction peak in the middle is significantly lower than that in the adjacent area. Figure 1 This indicates that the luminescent material prepared by the microwave synthesis method used in this application has significant and excellent crystallinity.

[0073] Appendix Figure 2 Cs2NaYb of Example 2 0.7 Bi 0.15 Mn 0.15 The room-temperature emission spectrum of Cl6 luminescent material under 360 nm light excitation shows that the main emission peak at this wavelength is at 588 nm, exhibiting a strong yellow-green downconversion light. (Attached) Figure 3 Cs2NaYb of Example 2 0.7 Bi 0.15 Mn 0.15 The room-temperature emission spectrum of Cl6 luminescent material under 980 nm light excitation shows that the main emission peak at this wavelength is at 563 nm, exhibiting strong green upconversion light. This demonstrates that by adjusting the elemental design and microwave synthesis method, the proposed method can successfully synthesize a luminescent material integrating both upconversion and downconversion luminescence capabilities. (Appendix) Figure 6 Cs2NaYb prepared for Comparative Example 2 0.1 Bi 0.15 Mn 0.75 The room-temperature emission spectra of the Cl6 luminescent material under excitation at 360 nm and 980 nm are shown in the figures. As can be seen from the figures, under 360 nm excitation, the main emission peak of the luminescent material is located at 587 nm, emitting yellow-green downconversion light, and its luminescence intensity is weaker than that of the downconversion luminescence in Example 2. Meanwhile, the attached... Figure 6It was also found that the luminescent material prepared in Comparative Example 2 failed to emit significant upconversion light within the detection range under 980 nm light excitation. Comparing Example 2 and Comparative Example 2, it is evident that only with specific amounts of Yb / Mn element doping can the prepared luminescent material produce significant up / down conversion dual-mode luminescence.

[0074] Appendix Figure 1 Cs2NaYb of Example 1 0.7 Bi 0.10 Mn 0.20 X-ray powder diffraction pattern of Cl6 luminescent material (with attached) Figure 7 The X-ray powder diffraction pattern of the luminescent material in Comparative Example 3 is shown in the attached diagram. Figure 1 and attached Figure 7 It can be seen that the product prepared in Example 1 is a single-phase sample with high crystallinity, while the product prepared in Comparative Example 3 is an amorphous sample. Comparing Example 1 and Comparative Example 3 shows that only by strictly controlling the microwave power can the prepared luminescent material have better crystallinity and phase purity.

[0075] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0076] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A metal halide dual-mode luminescent material, characterized in that, The chemical general formula of the metal halide dual-mode luminescent material is: Cs2NaYb 1-x-y Bi x Mn y Cl6, where x is 0 < x < 0.5 and y is 0 < y < 0.

5.

2. The metal halide dual-mode luminescent material according to claim 1, characterized in that, In the general chemical formula: 0.02≤x<0.4, 0.02≤y<0.

4.

3. The metal halide dual-mode luminescent material according to claim 1, characterized in that, In the general chemical formula: 0.05≤x<0.3, 0.05≤y<0.

3.

4. The metal halide dual-mode luminescent material according to claim 1, characterized in that, In the general chemical formula: x is 0.08, 0.1, 0.15, 0.1 or 0.3; y is 0.02, 0.05, 0.15, 0.2 or 0.

3.

5. A rapid microwave synthesis method for metal halide dual-mode luminescent materials according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Take the raw materials containing Cs, Na, Yb, Bi, and Mn elements and mix them evenly with hydrochloric acid solution to form a precursor solution; S2. Place the precursor solution in a microwave reactor and reflux it at a power of 300-800W for 1-60 minutes to obtain a reaction suspension. S3. The suspension is cooled, and after solid-liquid separation, washing, and drying, the metal halide dual-mode luminescent material is obtained.

6. The rapid microwave synthesis method according to claim 5, characterized in that, The raw materials for Cs, Na, Yb, Bi, and Mn are independently selected from at least one of their chlorides, oxides, nitrates, acetates, oxalates, and sulfates.

7. The rapid microwave synthesis method according to claim 5, characterized in that, The raw materials for the Cs, Na, Yb, Bi, and Mn elements are selected from their chlorides; the volume ratio of concentrated hydrochloric acid to deionized water in the hydrochloric acid solution is 1:0-10; In the precursor solution, the product Cs2NaYb is set to... 1-x-y Bi x Mn y The ratio of the amount of Cl6 to the volume of concentrated hydrochloric acid is 1 mmol: 1-30 mL.

8. The rapid microwave synthesis method according to claim 5, characterized in that, The reflux reaction time is 5-30 minutes.

9. The rapid microwave synthesis method according to claim 5, characterized in that, The solvent used in the washing process of S3 is at least one of ketone solvents and alcohol solvents. The ketone solvents include at least one of acetone and butanone. The alcohol solvents are selected from at least one of methanol, ethanol, isopropanol, n-propanol, and isobutanol. In the drying process of S3, the drying temperature is 60-120℃ and the drying time is 1-12h.

10. The rapid microwave synthesis method according to claim 9, characterized in that, The solvent used in the washing process of S3 is an alcohol solvent. In the drying process of S3, the drying temperature is 80-100℃ and the drying time is 3-6h.

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