A terbium calcium indium gallium zirconium garnet-based green light long-lasting phosphor and its application

Abstract

The present invention belongs to the technical field of inorganic luminescent materials, and specifically relates to a terbium calcium indium gallium zirconium garnet-based long-lasting green light phosphor and its application. The chemical composition of the phosphor is expressed as: Tb 2(1‑x) Gd 2x CaInGa3ZrO 12 , where 0≤x<1, and its synthesis process has no specific pressure or atmosphere requirements, and has the advantages of short synthesis time, simple preparation process, and low energy consumption. The phosphor of the present invention can be excited by broadband between 250 and 325 nm and narrowband between 350 and 380 nm, with the strongest emission being 543 nm narrowband green light, while also having strong luminescence between 475 and 500 nm. It can be used in the field of green light conversion materials for oral photocuring and ultraviolet-near ultraviolet LED chip excitation. After the end of X-ray irradiation, the luminescence can still last for 10 seconds, and can be used in the field of high-energy ray detection and fluorescent anti-counterfeiting identification.

Description

Technical Field

[0001] The present invention belongs to the technical field of inorganic luminescent materials, and in particular relates to a terbium calcium indium gallium zirconium garnet-based green light long-afterglow phosphor and applications thereof. Background Art

[0002] Long-lasting luminescent materials exhibit excellent optical properties. They absorb and store energy from external radiation, such as ultraviolet light, visible light, and high-energy radiation. After a period of irradiation, they slowly release this stored energy as luminescence under certain conditions. Ion-doped long-lasting luminescent materials are important photoluminescent materials, offering advantages such as simple preparation processes, stable luminescence properties, and high reproducibility. Furthermore, the emission wavelength can be controlled by doping or co-doping with different central ions. This allows the preparation of long-lasting luminescent materials with varying luminescence properties, using different matrices and doping ions. This is an important method for preparing luminescent materials.

[0003] Long-lasting luminescent materials have been widely used in biomedicine, sensing, architectural decoration, information storage, anti-counterfeiting and encryption, and safety and emergency response. In recent years, long-lasting luminescent nanomaterials with tunable emission wavelengths have become a hot research topic due to their unique optical properties and potential applications in various fields.

[0004] The development of long-lasting luminescent materials spans hundreds of years. A variety of long-lasting luminescent material matrices have been developed, including sulfides, aluminates, silicates, and gallates; and different luminescence centers have been utilized, such as rare earth ions, transition metals, and heavy metal ions. Despite the numerous new long-lasting luminescent materials developed, however, materials with high luminescence intensity and excellent afterglow performance remain in short supply, making them difficult to meet practical application requirements. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a terbium calcium indium gallium zirconium garnet-based green light long afterglow phosphor and its application. The phosphor has high luminous intensity and an afterglow luminous time of 10s.

[0006] The technical solutions adopted are:

[0007] A terbium calcium indium gallium zirconium garnet-based green light long afterglow phosphor, the chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , where 0≤x<1;

[0008] The phosphor can be excited by a broadband between 250 and 325 nm and a narrowband between 350 and 380 nm, with the strongest emission peak appearing at 543 nm, and can also emit light between 475 and 500 nm.

[0009] Preferably, the method for preparing the phosphor comprises the following steps:

[0010] (1) Weighing: Weigh the raw materials containing terbium, gadolinium, calcium, indium, gallium and zirconium elements according to their chemical composition, and the stoichiometric ratio is 2-2x:2x:1:1:3:1, where 0≤x<1;

[0011] (2) Grinding: Grind and mix evenly, and place in a reaction container;

[0012] (3) Sintering: Sintering is performed in an air atmosphere, then cooled to room temperature, and ground to obtain the phosphor.

[0013] Preferably, the raw material containing terbium element is selected from a mixture of one or more of terbium oxide, terbium oxalate, terbium carbonate and terbium nitrate;

[0014] The raw material containing gadolinium element is selected from a mixture of one or more of gadolinium oxide, gadolinium oxalate, gadolinium carbonate and gadolinium nitrate;

[0015] The raw material containing calcium is selected from a mixture of one or more of calcium carbonate, calcium bicarbonate and calcium oxalate;

[0016] The raw material containing indium element is selected from indium oxide;

[0017] The raw material containing gallium element is selected from gallium oxide;

[0018] The raw material containing zirconium element is selected from zirconium oxide.

[0019] Preferably, during the sintering process, the temperature is raised from room temperature to 1100-1250° C. at a rate of 3-7° C. / min, and then the temperature is kept constant.

[0020] Preferably, the temperature is kept constant for 3.5 hours after the sintering process is heated.

[0021] Preferably, the phosphor can continue to emit light after the X-ray irradiation ends, and the afterglow time is 10 seconds.

[0022] The above-mentioned terbium calcium indium gallium zirconium garnet-based green light long-lasting phosphor is used in the fields of oral light curing, green light conversion materials excited by ultraviolet-near ultraviolet LED chips, high-energy ray detection and fluorescent anti-counterfeiting identification.

[0023] The TbCaInGaZrGarnet-based long afterglow green phosphor proposed by the present invention has traps of appropriate depth, and the energy in the traps can be gradually released to Tb after the X-ray irradiation ends. 3+ , and then obtain green long afterglow luminescence.

[0024] The green long-lasting phosphor proposed in the present invention uses a new garnet matrix constructed with calcium, indium, gallium and zirconium. Compared with the traditional garnet isomorphic system constructed with aluminum, silicon and alkaline earth metals, the reaction temperature of its solid-phase synthesis is greatly reduced, and the synthesis process has no specific pressure or atmosphere requirements.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The terbium calcium indium gallium zirconium garnet-based green phosphor of the present invention can be excited by both broadband (250-325 nm) and narrowband (350-380 nm) emission, with the strongest emission being a narrowband green light at 543 nm. It also exhibits relatively strong luminescence between 475 and 500 nm. It can be used in green light conversion materials excited by ultraviolet-near-ultraviolet LED chips and in the field of oral photocuring.

[0027] (2) The product obtained by the present invention has good crystallinity, high luminescence brightness, adjustable fluorescence lifetime, and significantly different lifetimes under different excitation wavelengths, and can be used in the field of fluorescence lifetime anti-counterfeiting identification technology.

[0028] (3) The terbium calcium indium gallium zirconium garnet-based green light phosphor of the present invention is sintered in one step at a temperature as low as 1100°C and only needs to react for 3.5 hours to form a phase. Compared with the traditional aluminum and silicon-based garnet isostructural system, the reaction temperature of its solid-phase synthesis is greatly reduced, the synthesis time is short, and the synthesis process has no specific pressure or atmosphere requirements. It has the advantages of simple preparation process and low energy consumption.

[0029] (4) The TbCaInGaZrGarnet-based green phosphor of the present invention continues to emit light after X-ray irradiation, with an afterglow duration of 10 seconds. It can be used in high-energy ray detection and luminescent anti-counterfeiting identification. The afterglow duration can be adjusted by adjusting the calcination temperature and time, within a range of 5 to 30 seconds. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the X-ray powder diffraction pattern of the TbCaInGaZr garnet-based green phosphor prepared in Example 1;

[0031] Figure 2 is the fluorescence excitation spectrum of the TbCaInGaZrGarnet-based green phosphor prepared in Example 2;

[0032] Figure 3 is the fluorescence emission spectrum of the TbCaInGaZr garnet-based green phosphor prepared in Example 3;

[0033] Figure 4 is the fluorescence emission spectrum of the TbCaInGaZr garnet-based green phosphor prepared in Example 4;

[0034] Figure 5is a time-resolved spectrum of the TbCaInGaZr garnet-based green phosphor prepared in Example 5 after being irradiated with X-rays;

[0035] Figure 6 is the fluorescence lifetime curve of the TbCaInGaZr garnet-based green phosphor prepared in Example 5;

[0036] Figure 7 This is the color coordinate diagram of the TbCaInGaZrGarnet-based green phosphor prepared in Example 5. DETAILED DESCRIPTION

[0037] The equipment and reagents used in the present invention are conventional commercial products in the art. The technical scheme of the present invention is further illustrated below by way of examples, but the present invention is not limited to the scope of the examples. It should be understood that some prior art or common knowledge may be omitted.

[0038] Example 1

[0039] A terbium calcium indium gallium zirconium garnet-based green light phosphor, the chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , wherein x=0.5. The preparation method of the phosphor comprises:

[0040] 0.6344g of gadolinium oxide (Gd2O3), 0.3503g of calcium carbonate (CaCO3), 0.4859g of indium oxide (In2O3), 0.9841g of gallium oxide (Ga2O3), 0.4313g of zirconium oxide (ZrO2), and 0.6542g of terbium oxide (Tb4O7) were weighed respectively. The above raw materials were ground evenly in an agate mortar and then placed in a reaction vessel to initiate a high-temperature solid-phase reaction. The temperature was raised from room temperature to 1100°C in a normal pressure air atmosphere at a heating rate of 5°C / min. After reaching the preset temperature, the temperature was maintained constant for 3.5 hours. After the temperature was naturally cooled, the green phosphor was ground evenly to obtain the green phosphor. The specific grinding method, reaction vessel, sintering equipment, etc. all adopt the methods and containers used in conventional operations in the prior art to easily achieve the purpose of the invention.

[0041] The X-ray powder diffraction pattern of the TbCaInGaZrGarnet-based green phosphor prepared in this example is shown in FIG. Figure 1 As shown, from Figure 1 It can be seen that the prepared phosphor is pure, meets the requirements, and is not doped with other elements.

[0042] Example 2

[0043] A terbium calcium indium gallium zirconium garnet-based green light phosphor, the chemical composition of the phosphor is expressed as: Tb2(1-x) Gd 2x CaInGa3ZrO 12 , wherein x=0.2. The preparation method of the phosphor comprises:

[0044] 1.0150 g of gadolinium oxide (Gd2O3), 0.3503 g of calcium carbonate (CaCO3), 0.4859 g of indium oxide (In2O3), 0.9841 g of gallium oxide (Ga2O3), 0.4313 g of zirconium oxide (ZrO2), and 0.2617 g of terbium oxide (Tb4O7) were weighed respectively, and the above raw materials were ground evenly in an agate mortar, and then placed in a reaction vessel to start a high-temperature solid-phase reaction. The temperature was raised from room temperature to 1100°C in a normal pressure air atmosphere at a heating rate of 5°C / min. After reaching the preset temperature, the temperature was maintained constant for 3.5 hours. After the reaction was completed, it was allowed to cool naturally and ground evenly to obtain a green light phosphor.

[0045] The fluorescence excitation spectrum of the TbCaInGaZrGarnet-based green phosphor prepared in this example is shown in FIG. Figure 2 As shown, from Figure 2 It can be seen from the figure that the phosphor can be excited by a broadband wavelength between 250 and 325 nm and a narrowband wavelength between 350 and 380 nm.

[0046] Example 3

[0047] A terbium calcium indium gallium zirconium garnet-based green light phosphor, the chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , wherein x=0.1. The preparation method of the phosphor comprises:

[0048] 1.1419 g of gadolinium oxide (Gd2O3), 0.3503 g of calcium carbonate (CaCO3), 0.4859 g of indium oxide (In2O3), 0.9841 g of gallium oxide (Ga2O3), 0.4313 g of zirconium oxide (ZrO2), and 0.1308 g of terbium oxide (Tb4O7) were weighed respectively, and the above raw materials were ground evenly in an agate mortar, and then placed in a reaction vessel to start a high-temperature solid-phase reaction. The temperature was raised from room temperature to 1200°C in a normal pressure air atmosphere at a heating rate of 5°C / min. After reaching the preset temperature, the temperature was maintained constant for 3.5 hours. After the reaction was completed, it was allowed to cool naturally and ground evenly to obtain a green light phosphor.

[0049] The fluorescence emission spectrum of the TbCaInGaZrGarnet-based green phosphor prepared in this example is shown in FIG. Figure 3 As shown, from Figure 3 It can be seen from the figure that the strongest emission of the phosphor is 543nm narrow-band green light, and it also has strong luminescence between 475 and 500nm.

[0050] Example 4

[0051] A terbium calcium indium gallium zirconium garnet-based green light phosphor, the chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , wherein x=0.05. The preparation method of the phosphor comprises:

[0052] 1.2053 g of gadolinium oxide (Gd2O3), 0.3503 g of calcium carbonate (CaCO3), 0.4859 g of indium oxide (In2O3), 0.9841 g of gallium oxide (Ga2O3), 0.4313 g of zirconium oxide (ZrO2), and 0.0654 g of terbium oxide (Tb4O7) were weighed respectively, and the above raw materials were ground evenly in an agate mortar, and then placed in a reaction vessel to start a high-temperature solid-phase reaction. The temperature was raised from room temperature to 1200°C in a normal pressure air atmosphere at a heating rate of 5°C / min. After reaching the preset temperature, the temperature was maintained constant for 3.5 hours. After the reaction was completed, it was allowed to cool naturally and ground evenly to obtain a green light phosphor.

[0053] The fluorescence emission spectrum of the TbCaInGaZrGarnet-based green phosphor prepared in this example is shown in FIG. Figure 4 As shown, the strongest emission is still around 543 nm, and the emission spectrum of the obtained phosphor is basically the same as that of the phosphor prepared in Example 3.

[0054] Example 5

[0055] A terbium calcium indium gallium zirconium garnet-based green light phosphor, the chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , wherein x=0.01. The preparation method of the phosphor comprises:

[0056] 1.2561 g of gadolinium oxide (Gd2O3), 0.3503 g of calcium carbonate (CaCO3), 0.4859 g of indium oxide (In2O3), 0.9841 g of gallium oxide (Ga2O3), 0.4313 g of zirconium oxide (ZrO2), and 0.0131 g of terbium oxide (Tb4O7) were weighed respectively, and the above raw materials were ground evenly in an agate mortar, and then placed in a reaction vessel to start a high-temperature solid-phase reaction. The temperature was raised from room temperature to 1250°C in a normal pressure air atmosphere at a heating rate of 5°C / min. After reaching the preset temperature, the temperature was maintained constant for 3.5 hours. After the reaction was completed, it was allowed to cool naturally and ground evenly to obtain a green light phosphor.

[0057] The time-resolved spectrum of the TbCaInGaZrGarnet-based green phosphor prepared in this example after being irradiated by X-rays is shown in FIG. Figure 5 As shown, from Figure 5 It can be seen from the figure that the phosphor can still continue to emit light after the X-ray irradiation ends, and the afterglow time is 10s. Figure 6 This is the fluorescence lifetime curve of the TbCaInGaZrGarnet-based green phosphor prepared in this example.

[0058] like Figure 7 As shown, the color coordinates of the TbCaInGaZrGarnet-based green phosphor prepared in this embodiment are (0.37, 0.55).

[0059] In Examples 1-5, the change in the value of x has no effect on the performance of the prepared TbCaInGaZrGarnet-based green phosphor, and within the sintering temperature range, the performance of the obtained product meets the requirements.

[0060] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the scope of protection of the present invention.

Claims

1. A terbium calcium indium gallium zirconium garnet-based green long-lasting phosphor, characterized in that: The chemical composition of the phosphor is expressed as: Tb 2(1-x) Gd 2x CaInGa3ZrO 12 , where x=0.99; The phosphor can be excited by a broadband wavelength between 250 and 325 nm and a narrowband wavelength between 350 and 380 nm, with the strongest emission peak occurring at 543 nm and luminescence occurring between 475 and 500 nm. The method for preparing the phosphor comprises the following steps: (1) Weighing: Weigh the raw materials containing terbium, gadolinium, calcium, indium, gallium and zirconium according to their chemical composition, with the stoichiometric ratio being 2-2x:2x:1:1:3:1, where x = 0.99; (2) Grinding: Grind and mix evenly, and place in a reaction container; (3) Sintering: Sintering is performed in an air atmosphere, followed by cooling to room temperature and grinding to obtain the phosphor; wherein, during the sintering process, the temperature is raised from room temperature to 1250°C at a rate of 5°C / min, and then the temperature is kept constant for 3.5 hours; The fluorescent powder can continue to emit light after the X-ray irradiation ends, and the afterglow time is 10 seconds.

2. The TbCaInGaZrGarnet-based green long-lasting phosphor according to claim 1, characterized in that: The raw material containing terbium element is selected from a mixture of one or more of terbium oxide, terbium oxalate, terbium carbonate and terbium nitrate; The raw material containing gadolinium element is selected from a mixture of one or more of gadolinium oxide, gadolinium oxalate, gadolinium carbonate and gadolinium nitrate; The raw material containing calcium is selected from a mixture of one or more of calcium carbonate, calcium bicarbonate and calcium oxalate; The raw material containing indium element is selected from indium oxide; The raw material containing gallium element is selected from gallium oxide; The raw material containing zirconium element is selected from zirconium oxide.

3. Application of the TbCaInGaZrGarnet-based green long-lasting phosphor according to any one of claims 1 or 2 in the fields of oral light curing, green light conversion materials excited by ultraviolet-near-ultraviolet LED chips, high-energy ray detection, and fluorescent anti-counterfeiting identification.

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