A method for preparing a carbon dot-based anti-blue light film

Abstract

The present invention relates to the field of novel display materials, quantum dot materials, and discloses a method for preparing a carbon dot-based anti-blue light film. (1) Perylene and PTCDA or perylene and propylene diamine are weighed as reaction precursors in a molar ratio of perylene:PTCDA / propylene diamine = (1-5) : 1; (2) Ethanol sulfuric acid solution or DMF is added to the above reaction precursors and placed in a hydrothermal reactor for a solvent thermal reaction; perylene: ethanol sulfuric acid solution or DMF = 1 mmol: (3-20) mL; (3) After the solvent thermal reaction is completed, the reaction solution is filtered, centrifuged, dialyzed, and finally dried to obtain carbon dots; (4) Polystyrene and carbon dots are mixed and dispersed in toluene, and spin-coated to obtain a carbon dot-based anti-blue light film. The carbon dots prepared by the present invention can be used to prepare anti-blue light films at a low doping ratio, and the CIE coordinates are not offset and the color is not distorted.

Description

Technical Field

[0001] The present invention belongs to the field of new display devices and new display materials, quantum dot materials, under 1.3 key directions of the core electronic industries in the 1.3.2 new display device category of the new generation of information technology industry in the catalog of strategic emerging industries, and specifically relates to a method for preparing a carbon dot-based anti-blue light film. Background Art

[0002] In an era dominated by digital and technological advancements, our exposure to artificial blue light has increased exponentially, and concerns about the potential adverse effects of blue light exposure are escalating. While exposure to natural blue light, such as sunlight, is essential for regulating circadian rhythms and promoting wakefulness, long-term exposure to artificial blue light emitted by electronic device screens has been linked to various ocular and systemic health issues, such as eye fatigue, sleep disturbances, and retinal damage. Consequently, the need for effective blue light mitigation strategies continues to grow.

[0003] Common anti-blue light additives, such as zinc oxide materials and non-ferrous metal materials, are not only expensive, but also cause biological toxicity that cannot be ignored. Therefore, there is an urgent need to develop low-cost, low-toxicity, and easy-to-process materials to construct anti-blue light films.

[0004] Carbon dots, as an emerging class of fluorescent nanomaterials, have excellent photoluminescence properties, tunable emission spectra, biocompatibility and simple synthesis methods, and play an indispensable role in the fields of biology, optoelectronic devices, energy conversion and storage.

[0005] However, the carbon dot-based anti-blue light films reported in the literature still face difficulties in commercialization. This is mainly because their absorbance is too strong, which causes color distortion and leads to a sharp shift in CIE coordinates. Therefore, it is particularly important to develop carbon dots that can be comparable to commercial anti-blue light lenses / films and avoid color distortion. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing a carbon dot-based anti-blue light film.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] A method for preparing a carbon dot-based anti-blue light film comprises the following steps:

[0009] (1) Weigh perylene and PTCDA or perylene and propylene diamine as reaction precursors in a molar ratio of perylene:PTCDA / propylene diamine = (1-5) : 1;

[0010] (2) Add ethanolic sulfuric acid solution or DMF to the above reaction precursor and place it in a hydrothermal reactor for solvothermal reaction; the ethanolic sulfuric acid solution is a mixed solution composed of concentrated sulfuric acid and anhydrous ethanol in a volume ratio of (1-20) : 100; perylene: ethanolic sulfuric acid solution or DMF = 1 mmol: (3-20) mL;

[0011] (3) After the solvothermal reaction is completed, the reaction solution is filtered, centrifuged, dialyzed, and finally dried to obtain carbon dots;

[0012] (4) With polystyrene as the main component and carbon dots as the dopant, the doping ratio of carbon dots is 0.01~1 wt%. Polystyrene and carbon dots are mixed and dispersed in toluene, and spin-coated to prepare a carbon dot-based anti-blue light film.

[0013] Preferably, the solvothermal reaction temperature is 160-240 °C and the reaction time is 4-24 h.

[0014] Preferably, the pore size of the filter paper used for filtration is 1-100 μm.

[0015] Preferably, the centrifugal speed is 6000-12000 rpm and the centrifugation time is 5-20 min.

[0016] Preferably, the dialysis bag used for dialysis has a molecular weight cut-off of 100-3000 Da, the dialysate is anhydrous ethanol, and the total dialysis time is 12-48 h.

[0017] Preferably, the amount of toluene used is 5-20 mL per 100 mg (polystyrene + carbon dots) based on the total mass of polystyrene and carbon dots.

[0018] Preferably, a spin coater is used during spin coating, with a spin coating speed of 100-10000 rpm and a spin coating time of 30-70 s.

[0019] Beneficial effects: The carbon dots prepared by the present invention can be used to produce anti-blue light films at a low doping ratio, and the CIE coordinates are not offset and the colors are not distorted; the preparation process of the present invention is simple and low-cost, and it is a convenient and environmentally friendly method for large-scale synthesis of anti-blue light films. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 : XRD pattern of carbon dots prepared in Example 1.

[0021] Figure 2 : Transmission electron microscopy image of carbon dots prepared in Example 1.

[0022] Figure 3 : Absorption diagram of the film with different carbon doping ratios prepared in Example 1.

[0023] Figure 4 : Transmittance diagram of the film with different carbon doping ratios prepared in Example 1.

[0024] Figure 5 : Spectra of thin films covered with white light LEDs (WLEDs) with different carbon doping ratios prepared in Example 1.

[0025] Figure 6 : Spectral graph of the iPhone 15 screen covered with thin films with different carbon doping ratios prepared in Example 1.

[0026] Figure 7 : Spectra of the films with different carbon doping ratios prepared in Example 1 covered with daylight.

[0027] Figure 8 : Example 1 is based on the CIE dot diagram of the film prepared by 0.01wt% carbon doping and Blank. DETAILED DESCRIPTION

[0028] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described below in conjunction with specific embodiments. It should be understood that the described embodiments are only a portion of the embodiments of the present invention, rather than all of them. Based on the described embodiments, all other embodiments derived by those skilled in the art without requiring creative effort are intended to fall within the scope of protection of the present invention.

[0029] Example 1

[0030] A method for preparing a carbon dot-based anti-blue light film, comprising the following steps:

[0031] (1) Take 1 mmol of perylene and 1 mmol of perylene tetracarboxylic dianhydride (PTCDA) powder, add them into a 25 mL hydrothermal reactor, add 10 mL of DMF, and perform solvothermal reaction at 200 °C for 8 h;

[0032] (2) After the solvothermal reaction in step (1), the solution was filtered through a filter paper with a pore size of 10 μm, and the filtrate was centrifuged at 8000 rpm for 10 min. Finally, the solution was dialyzed in anhydrous ethanol solution for 20 h using a dialysis bag with a molecular weight cutoff of 1000 Da, and freeze-dried to obtain pure carbon dots (CDs);

[0033] (3) Weigh carbon dots and polystyrene powders. The total mass of the mixed powder of carbon dots and polystyrene is 100 mg, and the mass proportion of carbon dots in the mixed powder is 0 wt% (Blank), 0.01 wt%, 0.05 wt%, 0.1 wt%, and 0.2 wt%. Add the mixed powders into 10 mL of toluene solution and dissolve them by ultrasonication.

[0034] (4) The solution obtained in step (3) was spin-coated at 3000 rpm for 40 s using a spin coater to obtain films with different carbon doping ratios.

[0035] Figure 1 The XRD pattern of the carbon dots prepared in Example 1 shows that o Characteristic peaks belonging to carbon appear on the left and right.

[0036] Figure 2 This is a transmission electron microscopy image of the carbon dots prepared in Example 1. It can be seen that the carbon dots exist and the size of the carbon dots is evenly distributed between 3 and 5 nm.

[0037] Figure 3 This is the absorption diagram of the film with different carbon doping ratios prepared in Example 1. It can be observed that with the increase of the carbon doping ratio, the absorption of the blue light band gradually increases.

[0038] Figure 4 This is a graph of the transmittance of the thin films with different carbon doping ratios prepared in Example 1. It can be observed that as the carbon doping ratio increases, the blue light band is gradually filtered out.

[0039] Figure 5 The spectra of the thin films covered with white light LEDs (WLEDs) with different carbon doping ratios prepared in Example 1 are shown in Figure 1. Figure 5 It can be seen that: compared with Blank, the addition of different carbon dots will reduce the peak intensity of the blue light region of white light LEDs, which proves the anti-blue light effect of carbon dot-based films on white light LEDs.

[0040] Figure 6 Spectral graph of iPhone 15 screen covered with thin films with different carbon doping ratios prepared in Example 1. Figure 6 It can be seen that: compared with Blank, the addition of different carbon dots will reduce the peak intensity of the blue light area of ​​the iPhone 15 screen, which proves the anti-blue light effect of the carbon dot-based film on the iPhone 15 screen.

[0041] Figure 7 The following is a spectrum of the film with different carbon doping ratios prepared in Example 1 covered with daylight. Figure 7 It can be seen that: compared with Blank, the addition of different carbon dots will reduce the peak intensity of the blue light region of sunlight, which proves the anti-blue light effect of carbon dot-based films on sunlight.

[0042] Figure 8The CIE dot diagram of the film prepared based on 0.01 wt% carbon doping and Blank in Example 1 is shown. It is not difficult to find that when 0.01 wt% carbon doping is used, both blue light protection and CIE coordinates are not shifted and color is not distorted.

[0043] Example 2

[0044] The difference from Example 1 is that "1,3-propylenediamine" is used instead of PTCDA; the rest are the same as Example 1.

[0045] Example 3

[0046] The difference from Example 1 is that the amount of perylene is changed to 5 mmol, 4 mmol, 3 mmol, and 2 mmol, respectively; the other steps are the same as Example 1.

[0047] Example 4

[0048] The difference from Example 2 is that the amount of perylene is changed to 5 mmol, 4 mmol, 3 mmol, and 2 mmol, respectively; the other steps are the same as Example 2.

[0049] Example 5

[0050] The difference from Example 1 is that 10 mL of DMF is replaced by "10 mL of ethanolic sulfuric acid solution", wherein the ethanolic sulfuric acid solution is composed of concentrated sulfuric acid (98 wt %) and anhydrous ethanol in a volume ratio of 10:100; the other steps are the same as Example 1.

Claims

1. A method for preparing a carbon dot-based anti-blue light film, characterized in that: The following steps are involved: (1) Weigh perylene and PTCDA or perylene and propylene diamine as reaction precursors in a molar ratio of perylene:PTCDA / propylene diamine = (1-5) : 1; (2) Add ethanolic sulfuric acid solution or DMF to the above reaction precursor and place it in a hydrothermal reactor for solvothermal reaction; the ethanolic sulfuric acid solution is a mixed solution composed of concentrated sulfuric acid and anhydrous ethanol in a volume ratio of (1-20) : 100; perylene: ethanolic sulfuric acid solution or DMF = 1 mmol: (3-20) mL; (3) After the solvothermal reaction is completed, the reaction solution is filtered, centrifuged, dialyzed, and finally dried to obtain carbon dots; (4) With polystyrene as the main component and carbon dots as the dopant, the doping ratio of carbon dots is 0.01~1 wt%. Polystyrene and carbon dots are mixed and dispersed in toluene, and spin-coated to prepare a carbon dot-based anti-blue light film.

2. The method for preparing the carbon dot-based anti-blue light film according to claim 1, wherein: The temperature of the solvothermal reaction is 160~240 ℃ and the time is 4~24 h.

3. The method for preparing the carbon dot-based anti-blue light film according to claim 1, wherein: The pore size of the filter paper used for filtration is 1~100 μm.

4. The method for preparing the carbon dot-based anti-blue light film according to claim 1, wherein: The centrifugal speed is 6000~12000 rpm and the centrifugation time is 5~20 min.

5. The method for preparing the carbon dot-based anti-blue light film according to claim 1, wherein: The molecular weight cutoff of the dialysis bag used in dialysis is 100~3000 Da, the dialysate is anhydrous ethanol, and the total dialysis time is 12~48 hours.

6. The method for preparing a carbon dot-based anti-blue light film according to claim 1, wherein: Based on the total mass of polystyrene and carbon dots, the amount of toluene used was 5–20 mL for every 100 mg (polystyrene + carbon dots).

7. The method for preparing a carbon dot-based anti-blue light film according to claim 1, wherein: A spin coater was used for spin coating, with a spin coating speed of 100-10,000 rpm and a spin coating time of 30-70 s.

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