Preparation method of carbon dot-based anti-blue light film

Abstract

The invention relates to the field of novel display material quantum dot materials, and discloses a preparation method of a carbon dot-based anti-blue light film. The preparation method comprises the following steps: (1) weighing perylene and PTCDA or perylene and propylene diamine as reaction precursors according to a molar ratio of perylene to PTCDA / propylene diamine of (1-5): 1; (2) adding an ethanol-sulfuric acid solution or DMF (Dimethyl Formamide) into the reaction precursor, and carrying out solvothermal reaction in a hydrothermal reaction kettle; the perylene: ethanol sulfuric acid solution or DMF = 1 mmol: (3-20) mL; (3) after the solvothermal reaction is completed, filtering, centrifuging and dialyzing a reaction solution, and finally drying to obtain the carbon dots; and (4) mixing and dispersing polystyrene and the carbon dots in toluene, and spin-coating to prepare the carbon dot-based anti-blue light film. The prepared carbon dots can be used for preparing an anti-blue-light film at a low doping ratio, CIE coordinates do not shift, and the color is not distorted.

Description

Technical Field

[0001] The present invention belongs to the field of 1.3.2 new display devices and new display materials, quantum dot materials, under 1.3.2 key directions of electronic core industries in the 1st new generation 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 have escalated. While exposure to natural blue light (e.g., sunlight) is essential for regulating circadian rhythms and promoting wakefulness, long-term exposure to artificial blue light emitted by electronic device screens has been associated with various ocular and systemic health problems (e.g., eye fatigue, sleep disturbances, and retinal damage). Therefore, the need for effective blue light mitigation strategies continues to increase.

[0003] Common anti-blue light additives, such as zinc oxide materials and non-ferrous metal materials, are not only expensive, but also bring biological toxicity that cannot be ignored. Therefore, it is urgent 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 drastic 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 deficiencies in the prior art, an object of the present invention is to provide a method for preparing a carbon dot-based anti-blue light film.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A method for preparing a carbon dot-based anti-blue light film comprises the following steps: (1) Weigh perylene and PTCDA or perylene and propylenediamine as reaction precursors in a molar ratio of perylene:PTCDA / propylenediamine = (1-5) : 1; (2) Add ethanol sulfuric acid solution or DMF to the above reaction precursor and place it in a hydrothermal reactor for solvothermal reaction; the ethanol sulfuric acid solution is a mixed solution of concentrated sulfuric acid and anhydrous ethanol in a volume ratio of (1-20) : 100; perylene: ethanol 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 obtain a carbon dot-based anti-blue light film.

[0008] Preferably, the solvothermal reaction temperature is 160-240 °C and the time is 4-24 h.

[0009] Preferably, the pore size of the filter paper used for filtration is 1-100 μm.

[0010] Preferably, the centrifugal speed is 6000-12000 rpm and the centrifugal time is 5-20 min.

[0011] Preferably, the dialysis bag used for dialysis has a molecular weight cutoff of 100-3000 Da, the dialysis fluid is anhydrous ethanol, and the total dialysis time is 12-48 h.

[0012] Preferably, based on the total mass of polystyrene and carbon dots, the amount of toluene used is 5-20 mL for every 100 mg (polystyrene + carbon dots).

[0013] Preferably, a coating machine is used during spin coating, the spin coating speed is 100-10000 rpm, and the spin coating time is 30-70 s.

[0014] Beneficial effects: 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 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

[0015] Figure 1 : XRD pattern of carbon dots prepared in Example 1.

[0016] Figure 2 : Transmission electron microscopy image of the carbon dots prepared in Example 1.

[0017] Figure 3 : Absorption diagram of the film with different carbon dot doping ratios prepared in Example 1.

[0018] Figure 4: Transmittance diagram of films with different carbon doping ratios prepared in Example 1.

[0019] Figure 5 : Spectral graphs of thin films covered with white light LEDs (WLEDs) with different carbon doping ratios prepared in Example 1.

[0020] Figure 6 : Spectral graph of the iPhone 15 screen covered with a thin film of different carbon doping ratios prepared in Example 1.

[0021] Figure 7 : Spectral graph of the films with different carbon doping ratios prepared in Example 1 covered with daylight.

[0022] Figure 8 : Example 1 CIE dot diagram of the film prepared based on 0.01wt% carbon dot doping and Blank. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the described embodiments, all other embodiments obtained by those skilled in the art without creative work belong to the protection scope of the present invention.

[0024] Example 1

[0025] A method for preparing a carbon dot-based anti-blue light film, the steps are as follows: (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; (2) After the solvothermal reaction in step (1), the solution was filtered through filter paper with a pore size of 10 μm, and then the filtrate was centrifuged at 8000 rpm for 10 min. Finally, it 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); (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 powder into 10 mL of toluene solution and dissolve it by ultrasonication. (4) The solution obtained in step (3) was spin-coated at 3000 rpm for 40 s using a coating machine to obtain films with different carbon doping ratios.

[0026] 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.

[0027] 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 in the range of 3 to 5 nm.

[0028] Figure 3 This is the absorption diagram of the film with different carbon doping ratios prepared in Example 1. It can be observed that as the carbon doping ratio increases, the absorption of the blue light band gradually increases.

[0029] Figure 4 This is a transmittance diagram of the film 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.

[0030] 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 FIG. Figure 5 It can be seen that: relative to Blank, the addition of different carbon dots will reduce the peak intensity of the blue light region of white light LEDs, proving the anti-blue light effect of carbon dot-based films on white light LEDs.

[0031] Figure 6 Spectrum 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: relative to Blank, the addition of different carbon dots will reduce the peak intensity of the blue light region of the iPhone 15 screen, which proves the anti-blue light effect of the carbon dot-based film for the iPhone 15 screen.

[0032] Figure 7 The following are the spectra of the films with different carbon doping ratios prepared in Example 1 covered with daylight. Figure 7 It can be seen that: relative to Blank, the addition of different carbon dots will reduce the peak intensity of the blue light region of sunlight, proving the anti-blue light effect of carbon dot-based films on sunlight.

[0033] Figure 8 The CIE dot diagram of the film prepared based on 0.01 wt% carbon dot doping and Blank in Example 1. It is not difficult to find that when 0.01 wt% carbon dot doping is used, both blue light protection and non-shift of CIE coordinates and color distortion can be achieved.

[0034] Example 2

[0035] The difference from Example 1 is that "1,3-propylenediamine" is used to replace PTCDA; the rest is the same as Example 1.

[0036] Example 3

[0037] 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 rest is the same as Example 1.

[0038] Example 4

[0039] 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 rest is the same as Example 2.

[0040] Example 5

[0041] The difference from Example 1 is that: 10 mL of DMF is replaced by "10 mL of ethanol sulfuric acid solution", wherein the ethanol sulfuric acid solution is composed of concentrated sulfuric acid (98 wt%) and anhydrous ethanol in a volume ratio of 10:100; the rest is 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 propylenediamine as reaction precursors in a molar ratio of perylene:PTCDA / propylenediamine = (1-5) : 1; (2) Add ethanol sulfuric acid solution or DMF to the above reaction precursor and place it in a hydrothermal reactor for solvothermal reaction; the ethanol sulfuric acid solution is a mixed solution of concentrated sulfuric acid and anhydrous ethanol in a volume ratio of (1-20) : 100; perylene: ethanol 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 obtain 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, characterized in that: 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, characterized in that: 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, characterized in that: The centrifugal speed is 6000~12000 rpm and the centrifugal time is 5~20 min.

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

6. The method for preparing the carbon dot-based anti-blue light film according to claim 1, characterized in that: 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 the carbon dot-based anti-blue light film according to claim 1, characterized in that: A coating machine is used for spin coating, the spin coating speed is 100~10000 rpm, and the spin coating time is 30~70 s.

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