Self-luminous composite material

Abstract

A self-luminescent composite material comprises a polymer matrix, a plurality of composite quantum dots dispersed in the polymer matrix, and a plurality of nano-metal particles dispersed in the polymer matrix. Each composite quantum dot includes a quantum dot and a plurality of ligands attached to its surface and having radioactive isotopes capable of emitting beta particles. The average particle size of the composite quantum dots is between 2 and 12 nanometers. Each quantum dot includes a core and a shell covering the outer surface of the core. The core has a structure of M1C1, and the shell has a structure of M2C2. M1 is selected from at least one of cadmium, zinc, and indium; C1 is selected from at least one of selenium and sulfur; M2 is selected from zinc; and C2 is selected from at least one of sulfur and selenium. The ligands are selected from fatty acids having radioactive isotopes.

Description

Technical Field

[0001] This invention relates to luminescent composite materials, and more particularly to a self-luminescent composite material containing quantum dots (QDs). Prior Technology

[0002] Based on the light-emitting properties of optoelectronic semiconductor compounds such as zinc sulfide (ZnS) and cadmium sulfide (CdS), and the optical tunability of quantum dots after nano-sizing, they are frequently used in applications such as photodiodes, amplifiers, and biomarkers. Researchers in this field have also invested a great deal of research and development in quantum dot-related technologies.

[0003] For example, patent application EP1715492A2 discloses a nuclear-powered quantum dot light source structure, which includes multiple quantum dots, multiple radioactive nuclei, and a matrix material covering the quantum dots and radioactive nuclei. The radioactive nuclei can be selected from those that emit alpha or beta particles. This nuclear-powered quantum dot light source structure provides energy to the quantum dots through the alpha or beta particles emitted by the radioactive nuclei, enabling them to emit fluorescence of a desired wavelength.

[0004] Therefore, improving the interaction between quantum dots and radioactive nuclei emitted α or β particles, thereby increasing energy utilization and enhancing fluorescence emission intensity, is one of the goals that researchers in related fields continue to strive for. Summary of the Invention

[0005] Therefore, the object of the present invention is to provide a self-luminous composite material with good luminous efficacy.

[0006] Therefore, the self-luminescent composite material of the present invention comprises a polymer matrix, a plurality of composite quantum dots dispersed in the polymer matrix, and a plurality of nano metal particles dispersed in the polymer matrix.

[0007] Each of the composite quantum dots comprises a quantum dot and a plurality of ligands attached to the surface of the quantum dot and having radioactive isotopes capable of emitting beta particles, and the average particle size of the composite quantum dots is between 2 and 12 nanometers.

[0008] Each quantum dot comprises a core and a shell covering the outer surface of the core. Ligands are attached to the outer surface of the shell and are selected from fatty acids having radioactive isotopes. The core has a structure of M1C1, and the shell has a structure of M2C2. M1 is selected from at least one of cadmium (Cd), zinc (Zn), and indium (In), and C1 is selected from at least one of selenium (Se), sulfur (S), and phosphorus (P). The shell has a structure of M2C2, where M2 is selected from zinc, and C2 is selected from at least one of sulfur and selenium.

[0009] The advantage of this invention is that by using fatty acids with radioactive isotopes as ligands, the composite quantum dots simultaneously possess luminescent quantum dots and are loaded with ligands containing radioactive isotopes capable of emitting β particles. Therefore, the composite quantum dots can be excited by emitting β particles through the ligands to emit fluorescence. Furthermore, the local surface plasma enhancement properties of these nano-metal particles can also amplify the fluorescence emission intensity. Simple Explanation of the Diagram

[0010] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: Figure 1 is a schematic diagram illustrating an embodiment of the self-luminous composite material of the present invention; and Figure 2 is a schematic diagram illustrating a method for preparing the self-luminous composite material of the present invention. Implementation

[0011] The technical content, features, and effects of this invention will be clearly presented in the following detailed description of the embodiments with reference to the accompanying drawings. Furthermore, it should be noted that the drawings of this invention are only for illustrating the structural and / or positional relationships between elements and are not related to the actual dimensions of each element.

[0012] Before the invention is described in detail, it should be noted that similar elements are represented by the same numbers in the following description.

[0013] Referring to Figure 1, an embodiment of a self-luminous composite material of the present invention includes a polymer matrix 2, a plurality of composite quantum dots 3 dispersed in the polymer matrix 2, and a plurality of nano metal particles 4 dispersed in the polymer matrix 2.

[0014] The polymer matrix 2 is a polyacrylic acid compound. By controlling the thickness of the polymer matrix 2, the fluorescence self-shielding effect and the absorption of radiation particles can be effectively avoided.

[0015] Each of the composite quantum dots 3 comprises a quantum dot and a plurality of ligands 33 connected to the surface of the quantum dot and having radioactive isotopes capable of emitting beta particles, and the average particle size of the composite quantum dots 3 is between 2 and 12 nanometers.

[0016] Each quantum dot comprises a core 31 and a shell 32 covering the outer surface of the core 31, with ligands 33 attached to the outer surface of the shell 32.

[0017] The core 31 has a structure of M1C1, where M1 is selected from at least one of cadmium, zinc, and indium, and C1 is selected from at least one of selenium and sulfur. The shell 32 has a structure of M2C2, where M2 is selected from zinc, and C2 is selected from at least one of sulfur and selenium.

[0018] More specifically, the core 31 can be composed of cadmium selenide (CdSe), cadmium sulfide (CdS), or cadmium zinc selenide (CdZnSe), and the shell 32 can be composed of zinc selenide (ZnSe), zinc sulfide (ZnS), or zinc selenide / zinc sulfide (ZnSe / ZnS). In this embodiment, cadmium selenide is used as the core 31 and zinc selenide is used as the shell 32, but this is not a limitation.

[0019] The ligands 33 are selected from fatty acids having radioactive isotopes. In this embodiment, the fatty acid having a radioactive isotope is oleic acid (OA). Oleic acid has a high boiling point (360°C), which helps stabilize the surface of the shells 32, effectively conducts heat, and stabilizes the reaction temperature. In addition, because oleic acid has a long hydrocarbon chain, it can prevent the aggregation of the composite quantum dots 3 and provide spatial hindrance for the growth of the composite quantum dots 3, slowing down the growth of the composite quantum dots 3, and making the size of the composite quantum dots 3 smaller and more uniform. Furthermore, in this embodiment, at least a portion of the carbon and hydrogen of the oleic acid is a radioactive isotope. That is, the carbon portion of the hydrocarbon chain of the oleic acid is replaced with carbon-14 (C14), or the hydrogen portion of the hydrocarbon chain of the oleic acid is replaced with tritium (3H), or the carbon and hydrogen portions of the hydrocarbon chain of the oleic acid are respectively replaced with carbon-14 and tritium.

[0020] The nano-metal particles 4 are selected from at least one of gold (Au), silver (Ag), and copper (Cu). When the fluorescent light emitted by the quantum dots irradiates the nano-metal particles 4, the free electrons of the nano-metal particles 4 couple with the electric field of the incident light to generate collective oscillations, forming surface plasmas that resonate with the light field, thereby creating a localized surface plasma enhancement effect and enhancing the fluorescence intensity. In this embodiment, the nano-metal particles 4 are illustrated using nano-gold particles as an example.

[0021] The aforementioned composite quantum dots 3 are obtained by the following steps.

[0022] Step (a): A fatty acid is added to a solution containing the M1 precursor to form a first mixed solution, and then heated to 230 to 330°C. The fatty acid is selected from oleic acid, which has a radioactive isotope. At least a portion of the carbon and hydrogen elements of the oleic acid are radioactive isotopes. The oleic acid is sourced from commercially available oleic acid with bio-tracking capabilities (selected from SHOWA's SBH-035A model). The M1 is selected from cadmium. The solution containing the M1 precursor is a solution containing trioctylphosphine cadmium (TOPCd) obtained by adding a cadmium-containing compound to trioctylphosphine (TOP).

[0023] Step (a) involves adding the radioactive isotope oleic acid to a solution containing trioctylphosphine cadmium (TOPCd) to obtain the first mixed solution, and heating the first mixed solution to a temperature range between 230 and 330°C.

[0024] Step (b) involves injecting a solution containing a C1 precursor into the first mixed solution at 300 to 340°C, reacting to form the core 31, and allowing the core 31 to grow to a particle size between 2 and 12 nanometers to obtain a second mixed solution.

[0025] In this case, C1 is selected from selenium, and the solution containing the C1 precursor is prepared in a similar manner to the solution containing the M1 precursor described above, except that a selenium-containing compound is added to trioctylphosphine (TOP) to form a solution containing trioctylphosphine selenide (TOPSe).

[0026] It should be noted that the particle size of these nuclei 31 can be monitored and their growth and particle size distribution calculated by observing the spectral absorption characteristics of these nuclei 31. Once the desired spectral characteristics are observed, the reaction can be stopped, thereby controlling the particle size distribution range of these nuclei 31.

[0027] Step (c) involves adding a solution containing an M2 precursor and a solution containing a C2 precursor to the second mixed solution at 270 to 340°C and holding the temperature for a predetermined time, so that a shell 32 composed of M2 and C2 grows on the surface of the nucleus 31, and the oleic acid with radioactive isotopes is attached to the surface of the shell 32 to become the ligands 33.

[0028] Wherein, M2 is selected from zinc, and C2 is selected from selenium. The solution containing the M2 precursor is formed by heating the aforementioned oleic acid with radioactive isotopes and zinc-containing compounds to a temperature range of 270 to 340°C to form a solution containing zinc oleate (ZnOA), which is the solution containing the M2 precursor.

[0029] The solution containing the C2 precursor is prepared in a similar manner to the solution containing the M1 precursor described above, except that a selenium-containing compound or a sulfur-containing compound is added to trioctylphosphine to form a solution containing trioctylphosphine selenide or trioctylphosphine sulfide. This embodiment uses trioctylphosphine selenide as an example. Step (c) involves adding the solution containing zinc oleate (ZnOA) and the solution containing trioctylphosphine selenide to the second mixed solution and holding the reaction at a predetermined temperature for a predetermined time to obtain the composite quantum dots 3.

[0030] The self-luminescent composite material of the present invention can then be prepared using these composite quantum dots 3.

[0031] The method for preparing the self-luminous composite material using these composite quantum dots 3 is described below.

[0032] Referring to Figure 2, the preparation method of this self-luminous composite material embodiment includes a dispersion step, a film formation step, and a polymerization step.

[0033] Referring to Figure 2(a), the dispersion step involves mixing the composite quantum dots 3 with the nano-metal particles 4, a dispersant, and reactive monomers and / or reactive oligomers to form a mixed solution. The reactive monomers and reactive oligomers can be acrylic monomers or acrylic oligomers. The dispersant assists in dispersing the composite quantum dots 3 and the nano-metal particles 4 to prevent aggregation, and can be selected from poly(methyl methacrylate) (PMMA), polyethylene glycol (PEG), oleic acid, or trioctylphosphine oxide.

[0034] Referring to Figure 2(b), the film-forming step involves applying the mixed solution onto a thin sheet by spin coating, injection molding, or doctor blade coating to form a polymer. The thin sheet can be made of polyethylene (PE) or other transparent sheets, and its thickness can vary depending on requirements, and is not limited to polyethylene.

[0035] Referring to Figure 2(c), the polymerization step involves curing the polymer to be produced by irradiating it with ultraviolet light to form the polymer matrix 2, thereby obtaining the self-luminous composite material.

[0036] This self-luminescent composite material can be applied to a solar energy system. By combining the self-luminescent composite material of this invention with the solar energy system, the fluorescence emitted by the self-luminescent composite material is absorbed by the solar panel of the solar energy system and converted into electrical energy. The electrical energy is then connected to the external current loop through the wire unit and supplied to the outside.

[0037] In summary, this invention uses oleic acid with radioactive isotopes (carbon-14 and tritium) as a medium. During the synthesis of the composite quantum dots 3, the oleic acid with radioactive isotopes (carbon-14 and tritium) acts as ligands 33 and binds to the shells 32 of the composite quantum dots 3. A β-radioactive source is introduced into the composite quantum dots 3, causing the composite quantum dots 3 to emit fluorescence through the β-particles emitted by the ligands 33. Furthermore, the fluorescence emitted by the composite quantum dots 3 excites the localized surface plasma resonance effect generated by the nano-metal particles 4, thereby enhancing the fluorescence intensity of the composite quantum dots 3. Therefore, the objective of this invention is indeed achieved.

[0038] However, the above description is merely an embodiment of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the patent specification of the present invention shall still fall within the scope of the patent of the present invention.

[0039] 2: Polymer matrix 3: Composite quantum dots 31: Nucleus 32: Shell 33: Ligands 4: Nano-metal particles

Claims

1. A self-luminescent composite material comprising: a polymer matrix; a plurality of composite quantum dots with an average particle size between 2 and 12 nanometers dispersed in the polymer matrix, each composite quantum dot comprising a quantum dot and a plurality of ligands attached to the surface of the quantum dot and having a radioactive isotope capable of emitting β particles, wherein, Each quantum dot comprises a core and a shell covering the outer surface of the core, wherein ligands are attached to the outer surface of the shell and are selected from fatty acids having radioactive isotopes, the core has a structure of M1C1, the shell has a structure of M2C2, M1 is selected from at least one of cadmium, zinc, and indium, C1 is selected from at least one of selenium and sulfur, M2 is selected from zinc, and C2 is selected from at least one of sulfur and selenium; and a plurality of nano-metal particles dispersed in the polymer matrix.

2. The self-luminous composite material as described in claim 1, wherein, The core has the structure of cadmium selenide, cadmium sulfide, or cadmium zinc selenide (CdZnSe), and the shell has the structure of zinc selenide, zinc sulfide, or zinc selenide / zinc sulfide.

3. The self-luminous composite material as described in claim 1, wherein, The fatty acid in question is oleic acid.

4. The self-luminous composite material as described in claim 1, wherein, The radioactive isotope is selected from at least one of carbon-14 (C14) and tritium (3H).

5. The self-luminous composite material as described in claim 1, wherein, The nano-metal particles are selected from at least one of gold, silver, and copper.

6. The self-luminous composite material as described in claim 1, wherein, The polymer matrix is ​​a polyacrylic acid compound.

7. The self-luminous composite material as described in claim 1, wherein, These composite quantum dots are obtained by the following method: adding a fatty acid to a solution containing an M1 precursor to form a first mixed solution and heating it to 230 to 330°C, wherein at least a portion of one of the carbon and hydrogen elements of the fatty acid is a radioactive isotope; injecting a solution containing a C1 precursor into the first mixed solution at 300 to 340°C to form a core composed of the M1C1 precursor, and allowing the core to grow to a particle size between 2 and 12 nanometers to obtain a second mixed solution; and adding a solution containing an M2 precursor and a solution containing a C2 precursor into the second mixed solution at 270 to 340°C and holding the temperature for a predetermined time to allow a shell composed of the M2C2 precursor to grow on the surface of the core, while the fatty acid acts as a ligand attached to the surface of the shell, thereby obtaining the composite quantum dots.

Images