Luminescent material, preparation method thereof and application of luminescent material in preparation of anti-counterfeiting mark

Abstract

The invention relates to the technical field of luminescent materials, in particular to a luminescent material, a preparation method thereof and application of the luminescent material in preparation of anti-counterfeiting marks. The luminescent material provided by the invention has a structure as shown in a formula I, naYF4: xM, yR formula I; wherein x is more than or equal to 0.01 and less than or equal to 0.25, and y is more than or equal to M is one or more of Pr, Sm, Tm, Lu, La, Dy, Ho and Er; r is one or more of Ce, Yb and Nd. According to the luminescent material provided by the invention, fluoride NaYF4 is taken as a matrix, a trivalent rare earth ion M is taken as a luminescent center, and sensitizing ions R are combined, so that the effects that the luminescent material can be effectively excited by near-infrared light, the luminous intensity of generated visible light is relatively high, and the colors of the head and the tail of a light spot are different when the light spot is moved and excited are realized. When the luminescent material provided by the invention is applied to preparation of anti-counterfeiting marks, the anti-counterfeiting reliability can be well improved, and counterfeiting behaviors can be attacked.

Description

Technical Field

[0001] The invention relates to the technical field of luminescent materials, in particular to a luminescent material and a preparation method thereof and application thereof in the preparation of anti-counterfeiting marks. Background Art

[0002] Dynamic luminous anti-counterfeiting technology is of great significance in the field of anti-counterfeiting. It mainly introduces complex optical properties to make anti-counterfeiting marks difficult to copy and provide higher security for the authenticity verification of various products, documents and currencies. Multi-mode dynamic luminous anti-counterfeiting involves different luminous mechanisms, which can show different optical responses under specific external conditions. By adding multiple luminous mechanisms to anti-counterfeiting materials, multi-level information presentation can be achieved. Such complex anti-counterfeiting marks have high technical difficulties in preparation and imitation, which greatly increases the threshold for counterfeiting and makes the anti-counterfeiting verification process more intuitive and convenient. It can enhance the difficulty of anti-counterfeiting, realize multi-level information display, rapid identification and convenient verification, realize intelligence and digitization, and enhance brand image and product added value. Multi-mode dynamic luminous anti-counterfeiting technology provides multi-level protection for product authenticity verification by introducing complex optical effects and multiple response modes. It is an important technology to improve anti-counterfeiting reliability and combat counterfeiting. Summary of the invention

[0003] In view of this, the technical problem to be solved by the present invention is to provide a luminescent material and a preparation method thereof and an application in the preparation of anti-counterfeiting marks. The luminescent material provided by the present invention can be effectively excited by near-infrared light, and the generated visible light has a high luminous intensity, and the colors of the light spot at the beginning and end are different when the excitation spot is moved.

[0004] The present invention provides a luminescent material having a structure of formula I;

[0005] NaYF4: xM, yR Formula I;

[0006] Among them, 0.01≤x≤0.25, 0.2≤y≤0.45;

[0007] The M is one or more of Pr, Sm, Tm, Lu, La, Dy, Ho and Er;

[0008] The R is one or more of Ce, Yb and Nd.

[0009] The luminescent material provided in the present application is an up-conversion dynamic multicolor luminescent material, which uses fluoride NaYF4 as a matrix, trivalent rare earth ion M as a luminescent center, and combines with sensitizing ion R to achieve an effect that it can be effectively excited by near-infrared light, and the generated visible light has a high luminescent intensity, and the color of the light spot at the beginning and end is different when the excitation light spot is moved.

[0010] The M described in the present invention is a trivalent rare earth ion, preferably at least two of Pr, Sm, Tm, Lu, La, Dy, Ho and Er, more preferably at least two of Pr, Tm, La and Er, and even more preferably two or three of Pr, Tm, La and Er. The R described in the present invention is a sensitizing ion, preferably one or two of Ce, Yb and Nd, more preferably one or two of Ce and Yb.

[0011] In the luminescent material of the present invention, 0.01≤x≤0.25, preferably 0.015≤x≤0.15, more preferably 0.016≤x≤0.06, and even more preferably 0.016≤x≤0.02.

[0012] In the luminescent material of the present invention, 0.2≤y≤0.45, preferably 0.2≤y≤0.42, more preferably 0.2≤y≤0.25, and even more preferably 0.2≤y≤0.21.

[0013] More specifically, the luminescent material of the present invention has a structure of formula Ia;

[0014] NaYF4: xM, y1Yb, y2Ce Formula Ia;

[0015] Among them, x is the same as above and will not be repeated here;

[0016] y1+y2= y, and 0.2≤y1≤0.4, 0≤y2≤0.02; preferably, 0.2≤y1≤0.23, 0≤y2≤0.02; more preferably, y1=0.2, 0≤y2≤0.02.

[0017] In certain embodiments of the present invention, the luminescent material has a structure of formula II;

[0018] NaYF4: xEr, y1Yb, y2Ce Formula II;

[0019] Among them, x is the same as above and will not be repeated here;

[0020] y1+y2= y, and 0.2≤y1≤0.4, 0.01≤y2≤0.02; preferably, y1=0.4, y2=0.02.

[0021] In certain embodiments of the present invention, the luminescent material has a structure of formula III;

[0022] NaYF4: x1Pr, x2Er, y1Yb, y2Ce Formula III;

[0023] Wherein, x1+x2=x, and 0.01≤x1≤0.05, 0.005≤x2≤0.02; preferably, 0.01≤x1≤0.05, 0.01≤x2≤0.012; more preferably, x1=0.01, x2=0.01;

[0024] y1+y2= y, and 0.2≤y1≤0.4, 0.01≤y2≤0.02; preferably, 0.2≤y1≤0.23, 0.01≤y2≤0.02; more preferably, y1=0.2, y2=0.01.

[0025] In certain embodiments of the present invention, the luminescent material has a structure of Formula IV;

[0026] NaYF4: x1Pr, x2Er, x3La, y1Yb, y2Ce Formula IV;

[0027] Wherein, x1+x2+x3=x, and 0.01≤x1≤0.05, 0.004≤x2≤0.015, 0.001≤x3≤0.005; preferably, 0.01≤x1≤0.05, 0.01≤x2≤0.012, 0.001≤x3≤0.003; more preferably, x1=0.01, x2=0.01, x3=0.001;

[0028] y1+y2= y, and 0.2≤y1≤0.4, 0≤y2≤0.02; preferably, 0.2≤y1≤0.23, 0≤y2≤0.02; more preferably, y1=0.2, y2=0.

[0029] In certain embodiments of the present invention, the luminescent material has a structure of formula V;

[0030] NaYF4: x1Pr, x2Er, x3Tm, y1Yb, y2Ce Formula V;

[0031] Wherein, x1+x2+x3=x, and 0.01≤x1≤0.05, 0.004≤x2≤0.015, 0.001≤x3≤0.005; preferably, 0.01≤x1≤0.05, 0.005≤x2≤0.007, 0.001≤x3≤0.003; more preferably, x1=0.01, x2=0.005, x3=0.001;

[0032] y1+y2= y, and 0.2≤y1≤0.4, 0≤y2≤0.02; preferably, 0.2≤y1≤0.23, 0≤y2≤0.02; more preferably, y1=0.2, y2=0.

[0033] In some embodiments of the present invention, the luminescent material is NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.02Er, 0.4Yb, 0.02Ce, NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.05Pr, 0.01Er, 0.2Yb, One or more of 0.01Ce, NaYF4: 0.11Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.001La or NaYF4: 0.01Pr, 0.005Er, 0.2Yb, 0.001Tm.

[0034] In the luminescent material provided by the present invention, the factors affecting the luminescent properties mainly include the matrix, the luminescent center and the energy regulation center, and the luminescent center and the energy regulation center include trivalent rare earth ions M. The addition of trivalent rare earth ions M is to adjust the luminescent center of the material without changing the matrix crystal form, thereby adjusting the luminescent spectrum; the addition of sensitizing ions R is to increase the absorption of the color center and then transfer it to the luminescent center, and to assist the energy transfer between different energy levels of the luminescent center, so as to achieve the multicolor luminescence of the material under the same excitation light. The luminescent material provided by the present invention achieves the change of lifespan by adjusting the energy transfer path by adjusting the doped ions, and finally realizes that when the excitation spot on the moving material is different in color due to the moving direction and speed, so when the excitation spot is moved, the color of the spot at the beginning and the end is different.

[0035] The present invention also provides a method for preparing the luminescent material described in any of the above technical solutions, comprising the following steps:

[0036] Heat-treating materials including a sodium source, a yttrium source, an M source, and an R source to obtain an up-conversion dynamic multicolor luminescent material;

[0037] At least one of the sodium source, yttrium source, M source and R source contains fluorine.

[0038] The sodium source of the present invention is selected from one or more of sodium oxide, sodium nitrate, sodium chloride, sodium acetate, sodium trifluoroacetate, sodium fluoride, and sodium fluorosilicate. In certain embodiments of the present invention, the sodium source is selected from one or more of NaF or sodium fluorosilicate.

[0039] The yttrium source of the present invention is selected from one or more of yttrium oxide, yttrium nitrate, yttrium chloride, yttrium acetate, yttrium trifluoroacetate, yttrium fluoride, and yttrium fluorosilicate. In certain embodiments of the present invention, the yttrium source is selected from one or more of YCl3 or YF3.

[0040] The M source of the present invention is selected from one or more of oxides of M, nitrates of M, chlorides of M, acetates of M, trifluoroacetates of M, fluorides of M, and fluorosilicates of M. In certain embodiments of the present invention, the M source is selected from one or more of PrCl3, ErCl3, PrF3, or ErF3.

[0041] The R source of the present invention is selected from one or more of an oxide of R, a nitrate of R, a chloride of R, an acetate of R, a trifluoroacetate of R, a fluoride of R, and a fluorosilicate of R. In certain embodiments of the present invention, the R source is selected from one or more of YbCl3, CeCl3, YbF3, or CeF3.

[0042] In the preparation method of the luminescent material of the present invention, the molar ratio of the yttrium source, the M source and the R source is (0.5~1): (0.01~0.25): (0.2~0.45), preferably (0.5~1): (0.015~0.15): (0.2~0.42), more preferably (0.5~1): (0.016~0.06): (0.2~0.25), and even more preferably (0.5~1): (0.016~0.02): (0.2~0.21); the molar amount of the sodium source is 1 to 1.5 times the total molar amount of the yttrium source, the M source and the R source, preferably 1 to 1.3 times.

[0043] The present invention heat treats the mixture of the sodium source, the yttrium source, the M source and the R source. The mixing process is not particularly limited and can be performed by a mixing method known to those skilled in the art. The heat treatment method of the present invention includes a high temperature solid phase method, a hydrothermal method or a high temperature solvent method.

[0044] In some embodiments of the present invention, under a protective gas atmosphere, materials including a sodium source, a yttrium source, an M source and an R source are subjected to a high-temperature solid-phase reaction, the temperature of the high-temperature solid-phase reaction is 400°C~1000°C, and the time of the high-temperature solid-phase reaction is 0.5 h~24 h; the protective gas is selected from one or more of nitrogen, helium, neon or argon.

[0045] In some embodiments of the present invention, a material including a sodium source, a yttrium source, an M source, an R source and a surfactant is subjected to a hydrothermal reaction, the temperature of the hydrothermal reaction is 150°C to 200°C, and the time is 3 h to 10 h; the protective gas is selected from one or more of nitrogen, helium, neon or argon; and the surfactant is selected from polyvinyl pyrrolidone.

[0046] In some embodiments of the present invention, under a protective gas atmosphere, a material including a sodium source, a yttrium source, an M source and an R source is subjected to a high-temperature solvent reaction in a solvent, the solvent is oleic acid and 1,10-octadecene, the temperature of the high-temperature solvent reaction is 300°C~400°C, and the time of the high-temperature solvent reaction is 0.5 h~3 h; the protective gas is selected from one or more of nitrogen, helium, neon or argon.

[0047] The present invention also provides the use of the luminescent material described in any of the above technical solutions in the preparation of anti-counterfeiting marks. The anti-counterfeiting mark prepared by the luminescent material provided by the present invention can be effectively excited by near-infrared light, the generated visible light has high luminous intensity, and the color of the light spot at the beginning and end is different when the excitation light spot is moved.

[0048] The present invention provides a luminescent material and a preparation method thereof and an application thereof in the preparation of an anti-counterfeiting mark. The luminescent material provided by the present invention has a structure of formula I; NaYF4: xM, yR Formula I; wherein 0.01≤x≤0.25, 0.2≤y≤0.45; the M is one or more of Pr, Sm, Tm, Lu, La, Dy, Ho and Er; the R is one or more of Ce, Yb and Nd. The luminescent material provided by the present application is an up-conversion dynamic multicolor luminescent material, which uses fluoride NaYF4 as a matrix, trivalent rare earth ion M as a luminescent center, and combines with sensitizing ions R to achieve effective near-infrared light excitation, and the generated visible light luminescence intensity is high, and the color of the light spot at the beginning and the end is different when the excitation light spot is moved. At the same time, the luminescent material provided by the present invention has a simple preparation process, the product has stable chemical properties, is fluffy and very easy to grind, has no radioactivity, and does not cause harm to the environment. The luminescent material provided by the present invention is applied to the preparation of anti-counterfeiting marks, which can well improve the anti-counterfeiting reliability and combat counterfeiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a color change diagram of the dynamic dual-color luminescent material of Example 1 of the present invention under a moving excitation source;

[0050] Figure 2 This is the XRD diagram of the dynamic dual-color luminescent material of Example 1 of the present invention;

[0051] Figure 3 The luminescence spectrum of the dynamic two-color luminescent material of Example 1 of the present invention;

[0052] Figure 4 This is a color change diagram of the dynamic dual-color luminescent material of Example 9 of the present invention under a moving excitation source;

[0053] Figure 5 This is a color change diagram of the dynamic dual-color luminescent material of Example 10 of the present invention under a moving excitation source;

[0054] Figure 6 This is a color change diagram of the luminescent material of Comparative Example 1 of the present invention under a moving excitation source;

[0055] Figure 7 This is a color change diagram of the luminescent material of Comparative Example 2 of the present invention under a moving excitation source;

[0056] Figure 8 This is a color change diagram of the luminescent material of comparative example 3 of the present invention under a moving excitation source. DETAILED DESCRIPTION

[0057] The present invention discloses a luminescent material, a preparation method thereof, and an application thereof in the preparation of an anti-counterfeiting mark. A person skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve the same. It should be particularly noted that all similar substitutions and modifications are obvious to a person skilled in the art, and they are all deemed to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0058] The present invention will be further described below in conjunction with embodiments:

[0059] Example 1

[0060] The raw materials are YCl3 (analytical grade), PrCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and CeCl3 (spectral grade). The molar ratio between them is 0.77:0.01:0.01:0.2:0.01. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source, 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put in an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The obtained luminescent material is a white powder with the molecular formula NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light, such as Figure 1 As shown, Figure 1 Graph showing the color change of the dynamic dual-color luminescent material of Example 1 of the present invention under a moving excitation source. Figure 2 As shown, Figure 2 is the XRD diagram of the dynamic dual-color luminescent material of Example 1 of the present invention, Figure 2 It can be seen that the dynamic dual-color luminescent material of Example 1 of the present invention is hexagonal NaYF4. Figure 3 As shown, Figure 3 This is the luminescence spectrum of the dynamic two-color luminescent material of Example 1 of the present invention.

[0061] Example 2

[0062] The raw materials are YCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and CeCl3 (spectral grade). The molar ratio between them is 0.56:0.02:0.4:0.02. The raw materials are weighed according to the above ratio, dissolved in water and stirred, and 1.2 times the molar amount of NaF and 0.1g polyvinyl pyrrolidone as rare earth sources are added. After stirring evenly, they are placed in a high-temperature and high-pressure reactor, and then placed in an oven at 180°C for 10 hours, and naturally cooled to room temperature. The obtained luminescent material is a white powder with a molecular formula of NaYF4:0.02Er, 0.4Yb, 0.02Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0063] Example 3

[0064] The raw materials are YF3 (analytical grade), PrF3 (analytical grade), ErF3 (analytical grade), YbF3 (analytical grade), and CeF3 (spectral grade). The molar ratio between them is 0.77: 0.01: 0.01: 0.2: 0.01. The raw materials are weighed according to the above ratio, and 1.2 times the molar amount of NaF as the rare earth source is added. After mixing, it is placed in a tube furnace under nitrogen protection, roasted at 900°C for 10 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0065] Example 4

[0066] The raw materials are YF3 (analytical pure), PrF3 (analytical pure), ErF3 (analytical pure), YbF3 (analytical pure), and CeF3 (spectral pure). The molar ratio between them is 0.77: 0.01: 0.01: 0.2: 0.01. The raw materials are weighed according to the above ratio, and the same molar amount of NaF and 5wt% sodium fluorosilicate are added to the rare earth source. After mixing, they are placed in a tube furnace under nitrogen protection, roasted at 900℃ for 10 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0067] Example 5

[0068] The raw materials are YF3 (analytical pure), PrF3 (analytical pure), ErF3 (analytical pure), YbF3 (analytical pure), and CeF3 (spectral pure). The molar ratio between them is 0.73: 0.05: 0.01: 0.2: 0.01. The raw materials are weighed according to the above ratio, and the same molar amount of NaF and 5wt% sodium fluorosilicate are added to the rare earth source. After mixing, they are placed in a tube furnace under nitrogen protection, roasted at 900℃ for 10 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0069] Example 6

[0070] The raw materials are YF3 (analytical pure), PrF3 (analytical pure), ErF3 (analytical pure), YbF3 (analytical pure), and CeF3 (spectral pure). The molar ratio between them is 0.73: 0.05: 0.01: 0.2: 0.01. The raw materials are weighed according to the above ratio, and the same molar amount of NaF and 5wt% sodium fluorosilicate are added to the rare earth source. After mixing, they are placed in a tube furnace under nitrogen protection, roasted at 1000℃ for 10 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0071] Example 7

[0072] The raw materials are YF3 (analytical pure), PrF3 (analytical pure), ErF3 (analytical pure), YbF3 (analytical pure), and CeF3 (spectral pure). The molar ratio between them is 0.73:0.05:0.01:0.2:0.01. The raw materials are weighed according to the above ratio, and the same molar amount of NaF and 5wt% sodium fluorosilicate are added to the rare earth source. After mixing, they are placed in a tube furnace under nitrogen protection, roasted at 800℃ for 20 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0073] Example 8

[0074] The raw materials are YF3 (analytical pure), PrF3 (analytical pure), ErF3 (analytical pure), YbF3 (analytical pure), and CeF3 (spectral pure). The molar ratio between them is 0.67: 0.01: 0.01: 0.2: 0.01. The raw materials are weighed according to the above ratio, and the same molar amount of NaF and 5wt% sodium fluorosilicate are added to the rare earth source. After mixing, they are placed in a tube furnace under nitrogen protection, roasted at 900℃ for 10 hours, and naturally cooled to room temperature. The luminescent material obtained after grinding is a white powder with the molecular formula of NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce, which can be excited by 980 nm light to obtain a dynamic two-color luminescent material.

[0075] Example 9

[0076] The raw materials are YCl3 (analytical grade), PrCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and LaCl3 (spectral grade). The molar ratio between them is 0.779:0.01:0.01:0.2:0.001. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source, 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put into an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The obtained luminescent material is a white powder with the molecular formula NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.001La, which can be excited by 980 nm light. Figure 4 As shown, Figure 4 This is a color change diagram of the dynamic dual-color luminescent material of Example 9 of the present invention under a moving excitation source. Figure 4 It can be seen that according to the moving direction, the head of the light spot is green and the tail is yellow.

[0077] Example 10

[0078] The raw materials are YCl3 (analytical grade), PrCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and TmCl3 (spectral grade). The molar ratio between them is 0.784:0.01:0.005:0.2:0.001. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source, 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put in an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The luminescent material obtained is a white powder with the molecular formula NaYF4: 0.01Pr, 0.005Er, 0.2Yb, 0.001Tm. Figure 5 As shown, Figure 5 This is a color change diagram of the dynamic dual-color luminescent material of Example 10 of the present invention under a moving excitation source. Figure 5 It can be seen that according to the moving direction, the head of the light spot is orange and the tail is red.

[0079] Comparative Example 1

[0080] The raw materials are YCl3 (analytical grade), TbCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and CeCl3 (spectral grade). The molar ratio between them is 0.77:0.01:0.01:0.2:0.01. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source, 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put in an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The obtained luminescent material is a white powder with the molecular formula NaYF4: 0.01Tb, 0.01Er, 0.2Yb, 0.01Ce. Figure 6 As shown, Figure 6 This is a diagram showing the color change of the luminescent material of Comparative Example 1 of the present invention under a moving excitation source.

[0081] Comparative Example 2

[0082] The raw materials are YCl3 (analytical grade), ErCl3 (analytical grade), YbCl3 (analytical grade), and CeCl3 (spectral grade). The molar ratio between them is 0.78:0.01:0.2:0.01. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source and 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put in an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The luminescent material obtained is a white powder with the molecular formula of NaYF4:0.01Er, 0.2Yb, 0.01Ce. Figure 7 As shown, Figure 7This is a diagram showing the color change of the luminescent material of Comparative Example 2 of the present invention under a moving excitation source.

[0083] Comparative Example 3

[0084] The raw materials are YCl3 (analytical grade), PrCl3 (analytical grade), YbCl3 (analytical grade), EuCl3 (analytical grade), and GdCl3 (spectral grade). The molar ratio between them is 0.77:0.01:0.2:0.01:0.01. Weigh the raw materials according to the above ratio, dissolve them in water and stir, add 1.2 times the molar amount of NaF as a rare earth source, 0.1g polyvinyl pyrrolidone, stir evenly, place in a high-temperature and high-pressure reactor, and then put in an oven, place at 180°C for 10 hours, and cool naturally to room temperature. The obtained luminescent material is a white powder with the molecular formula NaYF4: 0.01Pr, 0.2Yb, 0.01Eu, 0.01Gd. Figure 8 As shown, Figure 8 This is a color change diagram of the luminescent material of comparative example 3 of the present invention under a moving excitation source.

[0085] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A luminescent material, characterized in that: It has the structure of formula I; NaYF4: xM, yR Formula I; Among them, 0.01≤x≤0.25, 0.2≤y≤0.45; The M is one or more of Pr, Sm, Tm, Lu, La, Dy, Ho and Er; The R is one or more of Ce, Yb and Nd.

2. The luminescent material according to claim 1, characterized in that The M is at least two of Pr, Tm, La and Er.

3. The luminescent material according to claim 1, characterized in that 0.015≤x≤0.15, 0.2≤y≤0.

42.

4. The luminescent material according to any one of claims 1 to 3, characterized in that It has the structure of Formula Ia; NaYF4: xM, y1Yb, y2Ce Formula Ia; Among them, y1+y2=y, and 0.2≤y1≤0.4, 0≤y2≤0.

02.

5. The luminescent material according to claim 4, characterized in that It has the structure of formula II; NaYF4: xEr, y1Yb, y2Ce Formula II; Among them, y1+y2= y, and 0.2≤y1≤0.4, 0.01≤y2≤0.02; Alternatively, it has the structure of formula III; NaYF4: x1Pr, x2Er, y1Yb, y2Ce Formula III; Among them, x1+x2=x, and 0.01≤x1≤0.05, 0.005≤x2≤0.02; y1+y2= y, and 0.2≤y1≤0.4, 0.01≤y2≤0.02; Alternatively, it has the structure of Formula IV; NaYF4: x1Pr, x2Er, x3La, y1Yb, y2Ce Formula IV; Among them, x1+x2+x3=x, and 0.01≤x1≤0.05, 0.004≤x2≤0.015, 0.001≤x3≤0.005; y1+y2= y, and 0.2≤y1≤0.4, 0≤y2≤0.02; Alternatively, it has the structure of Formula V; NaYF4: x1Pr, x2Er, x3Tm, y1Yb, y2Ce Formula V; Among them, x1+x2+x3=x, and 0.01≤x1≤0.05, 0.004≤x2≤0.015, 0.001≤x3≤0.005; y1+y2= y, and 0.2≤y1≤0.4, 0≤y2≤0.

02.

6. The luminescent material according to claim 5, characterized in that They are NaYF4: 0.01Pr, 0.01Er, 0.2Yb,0.01Ce、NaYF4: 0.02Er, 0.4Yb, 0.02Ce、NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce、NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.01Ce、NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce、NaYF4: 0.05Pr, 0.01Er, 0.2Yb, 0.01Ce、NaYF4: 0.05Pr, 0.01Er, 0.2Yb, One or more of 0.01Ce, NaYF4: 0.11Pr, 0.01Er, 0.2Yb, 0.01Ce, NaYF4: 0.01Pr, 0.01Er, 0.2Yb, 0.001La or NaYF4: 0.01Pr, 0.005Er, 0.2Yb, 0.001Tm.

7. The method for preparing the luminescent material according to any one of claims 1 to 6, characterized in that: The following steps are involved: Heat-treating materials including a sodium source, a yttrium source, an M source, and an R source to obtain a luminescent material; At least one of the sodium source, yttrium source, M source and R source contains fluorine.

8. The method for preparing a luminescent material according to claim 7, characterized in that: The sodium source is selected from one or more of sodium oxide, sodium nitrate, sodium chloride, sodium acetate, sodium trifluoroacetate, sodium fluoride, and sodium fluorosilicate; The yttrium source is selected from one or more of yttrium oxide, yttrium nitrate, yttrium chloride, yttrium acetate, yttrium trifluoroacetate, yttrium fluoride, and yttrium fluorosilicate; The M source is selected from one or more of an oxide of M, a nitrate of M, a chloride of M, an acetate of M, a trifluoroacetate of M, a fluoride of M, and a fluorosilicate of M; The R source is selected from one or more of R oxides, R nitrates, R chlorides, R acetates, R trifluoroacetates, R fluorides, and R fluorosilicates.

9. The method for preparing a luminescent material according to claim 7, characterized in that: Under a protective gas atmosphere, the materials including the sodium source, the yttrium source, the M source and the R source are subjected to a high-temperature solid phase reaction, wherein the temperature of the high-temperature solid phase reaction is 400° C. to 1000° C., and the time of the high-temperature solid phase reaction is 0.5 h to 24 h; or, The materials including the sodium source, the yttrium source, the M source and the R source are subjected to a hydrothermal reaction at a temperature of 150° C. to 200° C. for a time of 3 h to 10 h; or, Under a protective gas atmosphere, a material including a sodium source, a yttrium source, an M source and an R source is subjected to a high-temperature solvent reaction in a solvent, wherein the solvent is oleic acid and 1,10-octadecene, the temperature of the high-temperature solvent reaction is 300° C. to 400° C., and the time of the high-temperature solvent reaction is 0.5 h to 3 h.

10. Use of the luminescent material according to any one of claims 1 to 6 in the preparation of anti-counterfeiting labels.

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