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CN-122012079-A - Preparation method of self-assembled talcum powder-loaded room-temperature phosphorescence carbon dots

CN122012079ACN 122012079 ACN122012079 ACN 122012079ACN-122012079-A

Abstract

The invention discloses a preparation method of self-assembled talcum powder-loaded room-temperature phosphorescent carbon dots. And (3) grinding and mixing citric acid, phenylenediamine and talcum powder according to the mass ratio, carrying out temperature programming on the obtained mixture under the vacuum and nitrogen protection conditions, carrying out constant-temperature reaction, naturally cooling, and grinding into powder to obtain the self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot material. The invention utilizes the limiting domain and rigidity enhancement effect of the talcum powder two-dimensional lamellar structure to effectively inhibit non-radiative transition and stabilize triplet excitons, thereby realizing the double emission of blue fluorescence and green long afterglow phosphorescence, and the afterglow time can reach 18 s at the longest. According to the invention, talcum powder is introduced to obtain the material with fluorescence and phosphorescence, so that the optical property is stronger, and the application field and the application effect are greatly expanded. The method has the advantages of simple process, higher yield and good repeatability, and the self-assembled talcum powder-loaded room temperature phosphorescent carbon dot material has good application prospect in the fields of photoelectric devices, anti-counterfeiting encryption, biosensing, environment monitoring and the like.

Inventors

  • WANG YINMU
  • JI YUNYUN
  • QIN AIMIAO
  • QIN YINGXI
  • WU JINJUN

Assignees

  • 苏州优矿塑新材料股份有限公司
  • 桂林理工大学

Dates

Publication Date
20260512
Application Date
20260317

Claims (8)

  1. 1. The preparation method of the self-assembled talcum powder-loaded room-temperature phosphorescence carbon dot is characterized by comprising the following steps: (1) Weighing citric acid, phenylenediamine and talcum powder according to the mass ratio of 1-5:1-5, and grinding in a mortar until the materials are completely and uniformly mixed; (2) Transferring the solid mixture obtained in the step (1) into a reaction crucible, and placing the reaction crucible into a program temperature-controlled tubular furnace for vacuumizing-nitrogen charging circulation treatment; (3) Setting the temperature of the tube furnace to be 100-300 ℃ and carrying out constant-temperature reaction in a flowing nitrogen atmosphere; (4) After the reaction is finished, naturally cooling to room temperature, and grinding the obtained product into powder to obtain a crude product of carbon dots; (5) And dissolving the obtained carbon dot crude product, and carrying out reprecipitation and purification treatment to obtain the self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot.
  2. 2. The method for preparing the self-assembled talcum powder-loaded room temperature phosphorescent carbon dot according to claim 1, wherein the phenylenediamine is o-phenylenediamine, m-phenylenediamine or p-phenylenediamine.
  3. 3. The method for preparing the self-assembled talcum powder-loaded room temperature phosphorescent carbon dots according to claim 1, wherein the number of talcum powder is 3000-5000.
  4. 4. The method for preparing the self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot according to claim 1, wherein the mass ratio of citric acid to phenylenediamine to talcum powder in the step (1) is 2:1:1.
  5. 5. The method for preparing the self-assembled talc powder supported room temperature phosphorescent carbon dot according to claim 1, wherein the number of times of vacuum pumping in the step (2) is at least 3.
  6. 6. The method for preparing the self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot according to claim 1, wherein the constant-temperature reaction time in the step (3) is 1-6 hours.
  7. 7. The method for preparing the self-assembled talc powder supported room temperature phosphorescent carbon dot according to claim 1, wherein the constant temperature reaction time in the step (3) is 2 hours.
  8. 8. The method for preparing the self-assembled talc powder supported room temperature phosphorescent carbon dot according to claim 1, wherein the mesh number of the talc powder is 4000.

Description

Preparation method of self-assembled talcum powder-loaded room-temperature phosphorescence carbon dots Technical Field The invention relates to the field of afterglow nanomaterials, in particular to a preparation method of self-assembled talcum powder-loaded room temperature phosphorescent carbon dots. Background Room temperature phosphorescent carbon dots (RTP-CDs) refer to carbon dot materials CDs that are capable of producing phosphorescent emissions upon excitation with light at room temperature. Phosphorus light is a photoluminescence phenomenon in which phosphorescence is released when a molecule absorbs light energy to transition to an excited state, enters a triplet state through intersystem crossing (ISC), and returns from the triplet state to a ground state. Unlike traditional fluorescence, phosphorescence has longer luminescence lifetime (usually in millisecond to second scale), and luminescence color and intensity can be regulated and controlled by material structure, and has advantages of low toxicity, good biocompatibility, good light stability, adjustability, afterglow signal, etc., and can be widely used in fields of anti-counterfeiting and information protection, biological imaging, environmental monitoring, photoelectric devices, light Emitting Diodes (LEDs), etc. The hydrothermal/solvothermal method is the most commonly used method for preparing phosphorescent carbon dots, and is usually carried out by mixing citric acid, urea, ethylenediamine and the like serving as precursors with deionized water or an organic solvent, placing the mixture in a high-pressure reaction kettle, and then carrying out high-temperature high-pressure carbonization reaction. In the reaction process, the precursor is dehydrated, polymerized, carbonized and doped with hetero atoms such as nitrogen/boron to form carbon points with room temperature phosphorescence characteristic, and the product is obtained through cooling, centrifuging, dialyzing and drying after the reaction is finished. But has the obvious technical defects of long reaction time, low phosphorescence quantum yield, easy quenching of triplet state by solvent and oxygen, non-uniform product particle size and luminescence property, poor batch repeatability, difficult precise regulation of phosphorescence service life and emission wavelength, easy quenching of phosphorescence in aqueous solution and limited practical application. Talcum powder (Talcum powder) is a mineral powder which takes hydrated magnesium silicate as a main component, has stable chemical property, better acid and alkali resistance, fire resistance and insulativity, and becomes a hot spot for people to study because of unique physical and chemical properties and wide application value. Meanwhile, the sheet structure of talcum powder can well load room temperature phosphorescence carbon dots RTP-CDs, strengthen the rigid structure and prolong the phosphorescence service life. And, the diversity of the preparation methods (electrochemical oxidation method, hydrothermal method, solvothermal method, etc.) greatly affects the loading effect on phosphorescence and further affects the phosphorescence performance. Therefore, a new material of talcum powder-loaded RTP-CDs is obtained by a rapid, efficient and scientific method, the application scene of the new material is expanded, and the new material has very important significance. Disclosure of Invention The invention aims to provide a preparation method of self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot, which is characterized in that talcum powder is introduced to obtain a material with fluorescence and phosphorescence, and the prepared self-assembled talcum powder-loaded room-temperature phosphorescent carbon dot material can realize double emission of blue fluorescence and green long afterglow phosphorescence, and the afterglow time can be 18 seconds at most. The technical scheme of the invention is that the preparation method of the self-assembled talcum powder-loaded room-temperature phosphorescence carbon dot comprises the following specific steps: (1) Weighing citric acid, phenylenediamine and talcum powder according to the mass ratio of 1-5:1-5, and grinding in a mortar until the mixture is completely and uniformly mixed; (2) Transferring the solid mixture obtained in the step (1) into a reaction crucible, and placing the reaction crucible into a program temperature-controlled tubular furnace for vacuumizing-nitrogen charging circulation treatment; (3) Setting the temperature to be 100-300 ℃, and reacting at constant temperature in flowing nitrogen atmosphere, so that citric acid and phenylenediamine are subjected to dehydration condensation and aromatization reaction, and meanwhile, a rigid and fixed carbon point network structure is formed in situ under the limit of the talcum powder lamellar structure; (4) After the reaction is finished, naturally cooling to room temperature, and grinding the o