Method for in-situ preparation of carbon-dot-based multicolor circularly-polarized long-afterglow luminescent material

Abstract

The invention discloses a method for in-situ preparation of a carbon dot-based multicolor circularly polarized long-afterglow luminescent material. The carbon dot-based multicolor circularly polarized long-afterglow luminescent composite material which is cyan, green, yellow, orange and red in a solid state is successfully prepared from boric acid, amino acid and various dye molecules (niloran / rhodamine 6G / rhodamine B / sulfonyl rhodamine 101) through one-pot hydrothermal reaction. The preparation method is simple, feasible, high in designability and easy for large-scale production. The carbon dot composite material has unique resolution in time, afterglow color and space, and can be applied to the fields of advanced anti-counterfeiting, information encryption and the like.

Description

Technical Field

[0001] The invention relates to a method for in-situ preparation of a carbon dot-based multicolor circularly polarized long afterglow luminescent material, belonging to the field of new materials. Background Art

[0002] Circularly polarized luminescence refers to the phenomenon that a chiral luminescent substance emits left-handed or right-handed circularly polarized light after being excited. Circularly polarized luminescent materials have received extensive attention in the fields of information encryption, bioimaging, three-dimensional display, optoelectronic devices, etc. However, due to the instability of triplet excitons, the research progress of circularly polarized long afterglow luminescence with long lifetime and large Stokes shift is relatively slow compared with circularly polarized fluorescence based on singlet excited states. Most of the circularly polarized long afterglow luminescent materials reported so far include organometallic compounds, organic small molecules, polymers, and metal-doped inorganic substances. Most of these materials usually contain transition metals or require relatively strict synthesis conditions, are toxic and expensive, which greatly hinders their practical application. Therefore, it is urgent to develop non-toxic, low-cost, and easy-to-synthesize circularly polarized long afterglow luminescent materials.

[0003] Carbon dots are a new type of carbon-based luminescent nanoparticles, which are generally less than 10 nm in size. They have the characteristics of high photostability, low cost, good biocompatibility, easy surface modification, high water solubility, and adjustable luminescence color. In recent years, with the development of phosphorescent carbon dots and chiral carbon dots, carbon dot-based circularly polarized long afterglow materials have attracted people's attention. However, since the afterglow color of phosphorescent carbon dots is mainly concentrated in blue-green, it is difficult to prepare multi-color circularly polarized long afterglow luminescent materials. Phosphorescence resonance energy transfer (PRET) provides an effective and universal strategy for constructing multi-color circularly polarized long afterglow luminescent materials. However, most of the reported PRET systems usually require two steps. Carbon dots are first synthesized as energy donors and then mixed with energy acceptors to construct the PRET system, which is not conducive to large-scale industrial production. Therefore, it is of great scientific significance to develop a simple method for in situ preparation of carbon dot-based multi-color circularly polarized long afterglow luminescent materials. Summary of the invention

[0004] In order to solve the problem of difficulty in preparing multicolor circularly polarized long afterglow luminescent materials, the present invention provides a method for in-situ preparation of carbon dot-based multicolor circularly polarized long afterglow luminescent materials. The method is simple to operate, and a carbon dot-based multicolor circularly polarized long afterglow luminescent composite material with cyan, green, yellow, orange and red in the solid state is successfully prepared by one pot of hydrothermal boric acid, amino acid and various dye molecules.

[0005] (1) A method for in-situ preparation of a carbon dot-based circularly polarized long afterglow luminescent material, characterized in that the specific steps are as follows: 1. Dissolve boric acid and amino acid in deionized water and stir them thoroughly to make them evenly dispersed to obtain a mixed liquid.

[0006] 2. Transfer the mixed liquid to the reactor and react it in a forced air drying oven at 120-180 °C for 8-14 hours. After cooling to room temperature, take out the reaction product.

[0007] 3. Transfer the reaction product to a beaker and heat it again in a forced air drying oven at 150-200 °C for 2-4 hours to obtain a powder sample. During the heating process, cover the beaker with aluminum foil and poke small holes in the foil to prevent moisture from evaporating too quickly.

[0008] According to the present invention, the amino acid in step 1 is L- / D-arginine (Arg), but is not limited to L- / D-arginine, and lysine may also be used.

[0009] According to the present invention, the mass of the boric acid in step 1 is 2-3 g, and the mass of the amino acid is 0.6-1.5 g.

[0010] (2) A method for in-situ preparation of a carbon dot-based multicolor circularly polarized long afterglow luminescent material, characterized by the following specific steps: 4. Dissolve boric acid, L- / D-arginine and a certain amount of dye molecules in the aqueous solution, stir them thoroughly to make them dispersed evenly, and obtain a mixed liquid. The rest of the preparation process is the same as 1, 2, and 3, and finally a solid powder sample is obtained.

[0011] According to the present invention, the dye molecules described in step 4 are nile blue (NiB), rhodamine 6G (Rh6G), rhodamine B (RhB), sulforhodamine 101 (SR101), but are not limited to these dye molecules.

[0012] According to the present invention, the mass of the dye molecules in step 4 is 0.1-20 mg.

[0013] The technical key points of the present invention are as follows: (1) in-situ preparation of carbon dot-based circularly polarized long afterglow luminescent materials; (2) in-situ preparation of carbon dot-based multicolor circularly polarized long afterglow luminescent materials.

[0014] The outstanding features of the present invention are: (1) providing a method for in situ preparation of carbon dot-based multicolor circularly polarized long afterglow luminescent materials, which is simple, feasible, highly designable and easy to scale up; (2) by adding different types of dye molecules during the reaction, the circularly polarized afterglow color can be regulated by phosphorescence resonance energy transfer between the in situ generated carbon dots and the residual dyes; (3) the carbon dot composite material has unique resolution in time, afterglow color and space, and can be applied to advanced anti-counterfeiting and information encryption and other fields.

[0015] The advantage of the present invention is that a carbon dot-based multicolor circularly polarized long afterglow luminescent composite material with cyan, green, yellow, orange and red colors is successfully prepared in the solid state by one-pot hydrothermal boric acid, amino acids and various dye molecules (Nile Blue / Rhodamine 6G / Rhodamine B / Sulforhodamine 101). BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The circularly polarized long afterglow spectra of L-CDs-Arg obtained in Example 1 and D-CDs-Arg obtained in Example 2 are shown.

[0017] Figure 2 Circularly polarized long afterglow spectra of L-CDs-NiB obtained in Example 12 and D-CDs-NiB obtained in Example 13.

[0018] Figure 3 These are the circularly polarized long afterglow spectra of L-CDs-Rh6G obtained in Example 14 and D-CDs-Rh6G obtained in Example 15.

[0019] Figure 4 These are circularly polarized long afterglow spectra of L-CDs-RhB obtained in Example 16 and D-CDs-RhB obtained in Example 17.

[0020] Figure 5 These are the circularly polarized long afterglow spectra of L-CDs-SR101 obtained in Example 22 and D-CDs-SR101 obtained in Example 23.

[0021] Figure 6 for Figure 1-5 Combined circularly polarized long afterglow spectrum. DETAILED DESCRIPTION

[0022] (1) In-situ preparation of carbon dot-based circularly polarized long afterglow luminescent materials Example 1

[0023] 3 g of boric acid and 1 g of L-arginine were dissolved in 20 mL of deionized water and stirred thoroughly to obtain a mixed liquid. The mixed liquid was transferred to a polytetrafluoroethylene reactor (50 mL) and reacted at 150 °C for 10 h. After the reaction was completed, the reactor was naturally cooled to room temperature. The obtained solution was transferred to a beaker and heated again at 180 °C for 2 hours to obtain a powder sample. During the heating process, the beaker was covered with foil to prevent the water from evaporating too quickly. Finally, the carbon dot composite material L-CDs-Arg was obtained. Example 2

[0024] On the basis of Example 1, L-arginine was replaced by D-arginine, and other conditions remained unchanged, so as to finally obtain the carbon dot composite material D-CDs-Arg. Example 3

[0025] Based on Example 1, the reaction temperature was changed to 180°C, and other conditions remained unchanged. Example 4

[0026] Based on Example 1, the reaction temperature was changed to 200°C, and other conditions remained unchanged. Example 5

[0027] Based on Example 1, the reaction temperature was changed to 130°C, and other conditions remained unchanged. Example 6

[0028] On the basis of Example 1, the secondary heating temperature was changed to 160° C., and other conditions remained unchanged. Example 7

[0029] On the basis of Example 1, the secondary heating temperature was changed to 200°C, and other conditions remained unchanged. Example 8

[0030] On the basis of Example 1, the mass of boric acid was changed to 2 g, and other conditions remained unchanged. Example 9

[0031] On the basis of Example 1, the mass of boric acid was changed to 2.5 g, and other conditions remained unchanged. Example 10

[0032] On the basis of Example 1, the mass of L-arginine was changed to 0.8 g, and other conditions remained unchanged. Embodiment 11

[0033] On the basis of Example 1, the mass of L-arginine was changed to 1.5 g, and other conditions remained unchanged.

[0034] (2) In-situ preparation of carbon dot-based multicolor circularly polarized long afterglow luminescent materials Example 12

[0035] 3 g of boric acid, 1 g of L-arginine and 10 mg of Nilolan were dissolved in 20 mL of deionized water and stirred thoroughly to disperse them evenly to obtain a mixed liquid. The mixed liquid was transferred to a polytetrafluoroethylene reactor (50 mL) and reacted at 150 °C for 10 h. After the reaction was completed, the reactor was naturally cooled to room temperature. The obtained solution was transferred to a beaker and heated again at 180 °C for 2 hours to obtain a powder sample. During the heating process, the beaker was covered with foil to prevent the water from evaporating too quickly. Finally, the carbon dot composite material L-CDs-NiB was obtained. Example 13

[0036] On the basis of Example 12, L-arginine was replaced by D-arginine, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material D-CDs-NiB. Embodiment 14

[0037] On the basis of Example 12, Nile blue was replaced by Rhodamine 6G, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material L-CDs-Rh6G. Embodiment 15

[0038] On the basis of Example 14, L-arginine was replaced by D-arginine, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material D-CDs-Rh6G. Example 16

[0039] On the basis of Example 12, Nile blue was replaced by Rhodamine B, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material L-CDs-RhB. Embodiment 17

[0040] On the basis of Example 16, L-arginine was replaced by D-arginine, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material D-CDs-RhB. Embodiment 18

[0041] On the basis of Example 16, the mass of Rhodamine B was changed to 1 mg, and other conditions remained unchanged. Embodiment 19

[0042] On the basis of Example 16, the mass of Rhodamine B was changed to 4 mg, and other conditions remained unchanged. Embodiment 20

[0043] On the basis of Example 16, the mass of Rhodamine B was changed to 15 mg, and other conditions remained unchanged. Embodiment 21

[0044] On the basis of Example 16, the mass of Rhodamine B was changed to 20 mg, and other conditions remained unchanged. Embodiment 22

[0045] On the basis of Example 12, Nile blue was replaced by sulforhodamine 101, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material L-CDs-SR101. Embodiment 23

[0046] On the basis of Example 22, L-arginine was replaced by D-arginine, and other conditions remained unchanged, thereby finally obtaining the carbon dot composite material D-CDs-SR101.

Claims

1. A method for in-situ preparation of carbon dot-based circularly polarized long afterglow luminescent materials, characterized in that The specific steps are as follows: Dissolve boric acid and amino acid in deionized water, stir thoroughly to make them evenly dispersed, and obtain a mixed liquid. Transfer the mixed liquid to a reactor, react at 120-180 °C in a forced air drying oven for 8-14 hours, cool to room temperature, and take out the reaction product. Transfer the reaction product to a beaker, and reheat at 150-200 °C in a forced air drying oven for 2-4 hours to obtain a powder sample. During the heating process, cover the beaker with aluminum foil and poke small holes in the aluminum foil to prevent moisture from evaporating too quickly.

2. According to the present invention, the amino acid in claim 1 is L- / D-arginine, but is not limited to L- / D-arginine, lysine may also be used.

3. According to the present invention, the mass of the boric acid in claim 1 is 2-3 g, and the mass of the amino acid is 0.6-1.5 g.

4. A method for in-situ preparation of carbon dot-based multicolor circularly polarized long afterglow luminescent materials, characterized in that The specific steps are as follows: dissolve boric acid, amino acid and a certain amount of dye molecules in an aqueous solution, stir them thoroughly to make them dispersed evenly, and obtain a mixed liquid. The rest of the preparation process is the same as that of claim 1, and finally a solid powder sample is obtained.

5. According to the present invention, the dye molecules described in claim 4 are nile blue, rhodamine 6G, rhodamine B, sulforhodamine 101, but are not limited to these dye molecules.

6. According to the present invention, the mass of the dye molecule described in claim 4 is 0.1-20 mg.

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