Self-activated red light controllable fluorescent powder and preparation method thereof

Abstract

The invention discloses self-activated red-light controllable fluorescent powder and a preparation method thereof, and relates to the technical field of luminescent material preparation, the self-activated red-light controllable fluorescent powder has a chemical formula of Zn2-xMgxT iO4, 0 < = x < = 2, the self-activated red-light controllable fluorescent powder has high physical and chemical stability, and can be used for preparing luminescent materials. Red light with different intensities can be emitted by adjusting the excitation wavelength, the intensity and wavelength of red light emission can be controlled by adjusting the component proportion (especially the content of magnesium), red light with different wavelengths can be output, and the luminescence characteristic of the fluorescent powder can also be changed by adjusting the calcination temperature in the preparation process. According to the self-activated red light controllable fluorescent powder prepared by the preparation method, the red light of the emission spectrum of the fluorescent powder can be regulated and controlled by regulating and controlling the molar ratio of zinc ions to magnesium ions and the temperature, and moreover, the raw materials adopted by the preparation method are low in price, simple in preparation condition and free of pollution.

Description

Technical Field

[0001] The invention belongs to the technical field of luminescent material preparation, and in particular relates to a self-activated red light controllable phosphor and a preparation method thereof. Background Art

[0002] LED is known as the fourth generation of light source. It has the characteristics of energy saving, green environmental protection, safety, long life, low power consumption, low heat, small size, and high luminous efficiency. It is widely used in display, backlight, indoor lighting, plant growth and other fields. As an important solid luminescent material, phosphor is the main raw material for preparing LED. At present, commercial phosphors all need rare earth materials. However, rare earth materials are scarce and expensive, which is not conducive to sustainable development.

[0003] In recent years, self-excited phosphors have gradually attracted the attention of researchers. The literature (Journal of Molecular Structure. 2024, 1298: 137082) reported a BaLaMgTaO6 phosphor with a red (710nm) emission spectrum under 340nm excitation. The literature (J. Electron. Mater. 2018, 47: 4550) reported a Ba3BPO7 phosphor with green luminescence (540nm) under 270nm excitation. The literature (Inorganic Chemistry. 2018, 57 (7): 3963) reported a ZnAl2O4 phosphor with a blue (~450nm) and infrared (750-900nm) emission spectrum under 250nm excitation. The literature (Nanoscale.2018,10:19039) reported ZnGa2O4 phosphor, whose cathode ray luminescence is in blue (358-468nm) and red (705nm);

[0004] However, self-excited phosphors usually emit narrow-band light and have relatively low luminous efficiency. Moreover, the luminescent characteristics of self-excited phosphors are usually relatively fixed and difficult to adjust. At the same time, self-excited phosphors may be sensitive to environmental changes, resulting in performance degradation. Currently, there is a lack of research on self-activated phosphors with controllable broadband red light on the market. Summary of the invention

[0005] The purpose of the present invention is to provide a phosphor with controllable self-activated red light in order to solve the above problems.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] The present invention discloses a self-activated red light controllable phosphor, the molecular formula of which is Zn 2-x Mg x TiO4, where 0≤x≤2.

[0008] Another aspect of the present invention discloses a method for preparing a self-activated red light controllable phosphor, which specifically comprises the following steps:

[0009] S1, using compounds containing zinc ions, magnesium ions and titanium ions as raw materials, according to Zn 2+ :Mg 2+ :Ti 4+ =2 to 0:0 to 2:1 molar mass ratio of the compound containing zinc ions, the compound containing magnesium ions and the compound containing titanium ions are weighed;

[0010] S2, adding the weighed raw materials into an agate mortar for grinding and mixing, and calcining the mixed raw materials in an air atmosphere at a calcination temperature of 1000-1400° C. for 4 hours;

[0011] S3. The calcined mixture is naturally cooled to room temperature, and ground again to obtain a self-activated red light controllable phosphor.

[0012] Furthermore, the compound containing zinc ions is ZnO.

[0013] Furthermore, the compound containing magnesium ions is MgO.

[0014] Furthermore, the compound containing titanium ions is TiO2.

[0015] The present invention has at least the following beneficial effects: the self-activated red light controllable phosphor prepared by the present invention has a chemical formula of Zn 2-x Mg x TiO4, the self-activated red light controllable phosphor has high physical and chemical stability, can achieve red light emission of different intensities by adjusting the excitation wavelength, and can control the intensity and wavelength of red light emission by adjusting the component ratio (especially the magnesium content), and achieve red light output of different wavelengths. By adjusting the calcination temperature during the preparation process, the luminescence characteristics of the phosphor can also be changed. By regulating the molar ratio of zinc ions and magnesium ions and temperature regulation, the emission spectrum of the phosphor can be regulated. Moreover, the raw materials used in the preparation method are low-priced, the preparation conditions are simple, and there is no pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flow chart of the preparation of the self-activated red light controllable phosphor of the present invention;

[0017] Figure 2 is the XRD spectrum of the phosphor prepared in Example 1 of the present invention;

[0018] Figure 3 is the emission spectrum of the phosphor prepared in Example 1 of the present invention;

[0019] Figure 4 is the excitation spectrum of the phosphor prepared in Example 1 of the present invention;

[0020] Figure 5 is the XRD spectrum of the phosphor prepared in Example 2 of the present invention;

[0021] Figure 6 is the emission spectrum of the phosphor prepared in Example 2 of the present invention;

[0022] Figure 7 is the XRD spectrum of the phosphor prepared in Example 3 of the present invention;

[0023] Figure 8 This is the emission spectrum of the phosphor prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0024] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0025] like Figure 1 Shown

[0026] Example 1

[0027] Weigh 0.8 g of ZnO, 0.4 g of MgO, and 0.8 g of TiO2, mix them evenly, and place them in an agate mortar and grind them thoroughly for 30 minutes. Then place the ground sample in a crucible and calcine it in an air atmosphere at a temperature of 1300°C for 4 hours. Then allow the sample to cool naturally to room temperature. Finally, grind the sample again to obtain a white powdery ZnMgTiO4 sample.

[0028] X-ray diffraction (XRD) experiments were performed on white powdered ZnMgTiO4 samples. Figure 2 As shown, the data show that the main phase of the prepared sample is ZnMgTiO4, without other impurity phases, indicating that the prepared ZnMgTiO4 has a stable crystal structure, high purity, and all constituent elements exist in the desired phase state.

[0029] The emission spectrum experiment was carried out on the white powder ZnMgTiO4 sample, and the laser wavelength was set to 325nm. Figure 3As shown, the emission peaks are located at 680nm and 720nm respectively, and both peaks are in the red light range, indicating that the prepared ZnMgTiO4 sample has red light emission characteristics, and the intensities of the two peaks are similar, indicating that the prepared ZnMgTiO4 can simultaneously excite multiple luminescent states. This characteristic provides a basis for the controllability of red light, and the relative intensities of the two peaks can be changed by adjusting the excitation conditions.

[0030] The white powder ZnMgTiO4 sample was subjected to an excitation spectrum experiment, referring to Figure 4 As shown in the figure, it can be seen that when the monitoring wavelength is 720nm, the maximum excitation wavelength is 325nm. The excitation wavelength of 325nm means that there is an energy level structure inside the material, so that under the excitation of this wavelength, electrons can transition to a high energy state and then fall back to a lower energy state, thereby releasing energy to produce luminescence, providing an effective excitation condition to achieve red light emission.

[0031] Example 2

[0032] Weigh 0.4 g ZnO, 0.6 g MgO, and 0.8 g TiO2, mix them evenly, and grind them in an agate mortar for 30 minutes. Then, place the ground sample in a crucible and calcine it in an air atmosphere at a temperature of 1300°C for 4 hours. Then, let the sample cool naturally to room temperature, and finally grind it again to obtain white powder ZnO. 0.5 Mg 1.5 TiO4 samples.

[0033] White powder Zn 0.5 Mg 1.5 TiO4 samples were subjected to X-ray diffraction (XRD) experiments, referring to Figure 5 The results showed that the prepared Zn 0.5 Mg 1.5 The main phase of the TiO4 sample tends to Mg2TiO4, without other impurity phases. Compared with Example 1, it shows that the increase in the proportion of magnesium leads to phase transformation.

[0034] White powder Zn 0.5 Mg 1.5 The TiO4 sample was subjected to emission spectrum experiment, and the laser wavelength was set to 325nm. Figure 6 As shown in the figure, the emission peaks are located at 680nm and 720nm respectively, and the emission peak at 680nm is dominant. This shows that by adjusting the composition ratio (especially the magnesium content), the intensity and wavelength of red light emission can be controlled. This control makes the different compositions of ZnMgTiO4 and Zn 0.5 Mg 1.5 The TiO4 sample can adjust the emission characteristics to achieve red light output of different wavelengths.

[0035] Example 3

[0036] Weigh 0.4 g ZnO, 0.6 g MgO, and 0.8 g TiO2, mix them evenly, and grind them in an agate mortar for 30 minutes. Then, place the ground sample in a crucible and calcine it in an air atmosphere at a temperature of 1400°C for 4 hours. Then, let the sample cool naturally to room temperature, and finally grind it again to obtain white powder ZnO. 0.5 Mg 1.5 TiO4 samples.

[0037] White powder Zn 0.5 Mg 1.5 TiO4 samples were subjected to X-ray diffraction (XRD) experiments, referring to Figure 7 The results show that the prepared Zn 0.5 Mg 1.5 The main phase of the TiO4 sample tends to be Mg2TiO4, without any other impurity phases.

[0038] White powder Zn 0.5 Mg 1.5 The TiO4 sample was subjected to emission spectrum experiment, and the laser wavelength was set to 325nm. Figure 8 As shown in the figure, the emission peaks are located at 680nm and 720nm respectively, and the emission peak at 720nm is dominant. Compared with Example 1, it is shown that the increase in the proportion of magnesium leads to phase transition, indicating that by adjusting the composition ratio (especially the content of magnesium), the intensity and wavelength of red light emission can be controlled. This control makes ZnMgTiO4 and Zn 0.5 Mg 1.5 The TiO4 sample can adjust the emission characteristics to achieve red light output of different wavelengths. Compared with Example 2, the luminescence characteristics of the sample can be changed by adjusting the calcination temperature, indicating that the Zn 0.5 Mg 1.5 TiO4 has controllable luminescence properties.

[0039] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A self-activated red light controllable phosphor, characterized in that: The chemical formula of the phosphor is Zn 2-x Mg x TiO4, where 0≤x≤2.

2. A method for preparing the self-activated red light controllable phosphor according to claim 1, characterized in that: The following steps are involved: S1, using compounds containing zinc ions, magnesium ions and titanium ions as raw materials, according to Zn 2+ :Mg 2+ :Ti 4+ =2 to 0:0 to 2:1 molar mass ratio of the compound containing zinc ions, the compound containing magnesium ions and the compound containing titanium ions are weighed; S2, grinding and mixing the weighed raw materials, and calcining the mixed raw materials under air atmosphere; S3. The calcined mixture is naturally cooled to room temperature, and ground again to obtain a self-activated red light controllable phosphor.

3. The method for preparing a self-activated red light controllable phosphor according to claim 2, characterized in that: The compound containing zinc ions is ZnO.

4. The method for preparing a self-activated red light controllable phosphor according to claim 2, characterized in that: The compound containing magnesium ions is MgO.

5. The method for preparing a self-activated red light controllable phosphor according to claim 2, characterized in that: The compound containing titanium ions is TiO2.

6. The method for preparing a self-activated red light controllable phosphor according to claim 2, characterized in that: The calcination temperature is 1000-1400°C and the calcination time is 4 hours.

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