Polymer and cuprous oxide composite crystal particle and preparation method thereof

Abstract

The invention relates to the technical field of nano composite materials, in particular to a polymer and cuprous oxide composite crystal particle and a preparation method thereof. The specific technical scheme is as follows: the polymer-cuprous oxide composite crystal particle takes polymer nanoparticles as object particles and cuprous oxide as a host crystal, so that the object particles are dispersed in the host crystal to form the polymer-cuprous oxide composite crystal particle, the problem of oxygen vacancy defect distribution regulation and control in the cuprous oxide crystal is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of nanocomposite materials, and particularly relates to a polymer@cuprous oxide composite crystal particle and a preparation method thereof. Background Art

[0002] Cuprous oxide (Cu 2 2O) is a semiconductor material with rich reserves, low cost and non-toxicity on the earth. It has an antifluorite crystal structure with a direct band gap of 2-2.2 eV, and can absorb sunlight in a wide spectral range. Its narrow band gap and appropriate conduction band and valence band energies make it an ideal material for photocatalytic water splitting to produce hydrogen and photocatalytic degradation of organic pollutants. However, the catalytic efficiency of unmodified cuprous oxide is relatively low, which limits the wide application of cuprous oxide materials.

[0003] By utilizing the interaction between the surface functional groups of polymer nanoparticles and the crystal, the inlay of polymer nanoparticles in cuprous oxide crystals is realized, thereby constructing polymer@crystal composite crystal particles. Oxygen vacancies (V O O) and other defects are generated at the interface between polymer nanoparticles and the crystal, which endows the material with new physical and chemical properties or enhanced catalytic performance. In recent years, there have been numerous studies on oxygen vacancies. Oxygen vacancies generated in semiconductor crystals such as titanium dioxide (TiO 2 2), zinc oxide (ZnO), bismuth oxychloride (BiOCl) and tungsten trioxide (WO 3 3) have been widely studied. Generally speaking, methods for constructing oxygen vacancies include heat treatment, chemical reduction, ultraviolet irradiation and ion doping, etc. However, these methods usually require high energy input or complex procedures, and it is still a major challenge to control internal defects spatially. There is no relevant report on constructing oxygen vacancies by the controllable inlay of guest nanoparticles in cuprous oxide crystals. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a polymer@cuprous oxide composite crystal particle and a preparation method thereof. Amphiphilic block copolymer nanoparticles with uniform particle size distribution and good colloidal stability are synthesized by polymerization-induced self-assembly (PISA) mediated by reversible addition-fragmentation chain transfer (RAFT) polymerization, and then polymer@cuprous oxide composite crystal particles are synthesized in-situ. By changing the addition amount of the block copolymer nanoparticles, the inlay depth in cuprous oxide crystals is controlled, so as to realize the precise regulation of the spatial distribution of oxygen vacancies, and solve the problem of regulating the distribution of oxygen vacancy defects in cuprous oxide crystals.

[0005] To achieve the above object, the present invention is realized through the following technical solutions:

[0006] The present invention discloses a kind of polymer@cuprous oxide composite crystal particles. The composite crystal particles use polymer nanoparticles as guest particles and cuprous oxide as the host crystal, and the guest particles are dispersed in the host crystal to form polymer@cuprous oxide composite crystal particles.

[0007] Preferably, the guest nanoparticles are block copolymer nanoparticles or polymer surface-modified nanoparticles, with a particle size of 5 - 200 nm, and the size of the polymer@cuprous oxide composite crystal particles is 0.2 - 100.0 μm.

[0008] Correspondingly, a preparation method of polymer@cuprous oxide composite crystal particles is to disperse polymer nanoparticles in a cuprous oxide precursor solution, mix evenly, and heat to form polymer@cuprous oxide composite crystal particles; the polymer nanoparticles are block copolymer nanoparticles or polymer surface-modified nanoparticles; the cuprous oxide precursor solution is a mixed solution of copper sulfate, potassium hydroxide, ammonia water, and D-(+)-glucose.

[0009] Preferably, the preparation process of the polymer@cuprous oxide composite crystal particles is as follows: at 300 - 500 rpm, add a potassium hydroxide solution to a copper sulfate solution, add a polymer nanoparticle dispersion solution after 1 - 10 minutes, then sequentially add ammonia water and a D-(+)-glucose solution, and continue stirring; then react under oil bath conditions without stirring; after the reaction ends, centrifuge and wash in water to obtain polymer@cuprous oxide composite crystal particles.

[0010] Preferably, the volume ratio of the copper sulfate solution, potassium hydroxide solution, polymer nanoparticle dispersion solution, ammonia water, and D-(+)-glucose solution is 1200:60 - 600:1 - 60:1 - 20:60 - 600.

[0011] Preferably, the concentration of the copper sulfate solution is 0.01 - 0.5 mol / L, the concentration of the potassium hydroxide solution is 0.5 - 5 mol / L, the concentration of the polymer nanoparticles is 5 - 20%, w / w, the concentration of ammonia water is 5% - 28%, w / w, and the concentration of the D-(+)-glucose solution is 0.1 - 5 mol / L.

[0012] Preferably, the preparation process of the polymer nanoparticles is as follows: add a macromolecular chain transfer agent and an initiator to a solvent to dissolve, then add a monomer; after purging with an inert gas to remove oxygen, heat and stir to polymerize to form block copolymer nanoparticles;

[0013] The macromolecular chain transfer agent is polymethacrylic acid glycerol ester modified with a single-terminal dithioester, the initiator is an azo initiator, and the monomer is a methacrylate.

[0014] Preferably, the molar ratio of the macromolecular chain transfer agent, initiator and monomer is 1:5:50-500, the solvent is water, and the ratio of the total mass of the macromolecular chain transfer agent, initiator and monomer to the mass of the solvent is 1:4-19.

[0015] Preferably, inert gas is introduced for deoxygenation in an ice-water bath for 15-25 min, and then the reaction is carried out in an oil bath at 50-70 °C for 12-36 h, and the stirring speed is 500-650 rpm.

[0016] The present invention has the following beneficial effects:

[0017] 1. The present invention provides a simple method to embed guest nanoparticles into cuprous oxide crystals to obtain a class of polymer@cuprous oxide composite crystal particles. Oxygen vacancies are generated at the interface between the guest nanoparticles and the cuprous oxide crystals, and the embedding depth is regulated by changing the nanoparticle concentration, thereby regulating the spatial distribution of oxygen vacancies in the cuprous oxide crystals. This method solves the problem of regulating the distribution of oxygen vacancy defects in cuprous oxide crystals.

[0018] 2. The amphiphilic block copolymer nanoparticles with uniform particle size distribution and good colloidal stability are synthesized by polymerization-induced self-assembly mediated by reversible addition-fragmentation chain transfer polymerization. The hydroxyl (-OH) functional groups contained in the surface stabilizing chains of the block copolymer nanoparticles can strongly interact with Cu + As the crystal grows, the guest nanoparticles are embedded into the cuprous oxide crystals to obtain polymer@cuprous oxide composite crystal particles. Description of the Drawings

[0019] Figure 1 Transmission electron microscope photograph of the block copolymer nanoparticles poly(glycerol methacrylate) 51 -poly(benzyl methacrylate) 100 prepared in Example 1;

[0020] Figure 2 Low-magnification scanning electron microscope photograph of the pure cuprous oxide crystal particles prepared in Example 2, and scanning electron microscope photograph of the cross-section of a single pure cuprous oxide crystal obtained after argon ion beam milling;

[0021] Figure 3 Low-magnification scanning electron microscope photograph of the polymer@cuprous oxide crystal particles prepared in Example 3, and scanning electron microscope photograph of the cross-section of a single polymer@cuprous oxide composite crystal obtained after argon ion milling;

[0022] Figure 4Low-magnification scanning electron microscope photograph of the polymer@cuprous oxide crystal particles prepared in Example 4, and scanning electron microscope photograph of the cross-section of a single polymer@cuprous oxide composite crystal obtained after argon ion milling;

[0023] Figure 5 Electron paramagnetic resonance spectra of the pure cuprous oxide crystal particles and polymer@cuprous oxide crystal particles prepared in Examples 2-4. Detailed implementation manners

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Unless otherwise specified, the technical means used in the implementation examples are conventional means well known to those skilled in the art.

[0026] 1. The present invention discloses a polymer@cuprous oxide composite crystal particle, which is a polymer@cuprous oxide composite crystal particle formed by taking block copolymer nanoparticles as guest particles and cuprous oxide as the host crystal, that is, the guest particles are dispersed in the host crystal. The particle size of the block copolymer nanoparticles is 5-200 nm, and the size of the polymer@cuprous oxide composite crystal particle is 0.2-100.0 μm. As another implementation manner, nanoparticles surface-modified with polymers can also be used as guest particles, such as gold nanoparticles, silica nanoparticles, and metal-organic framework nanoparticles.

[0027] 2. The present invention discloses a preparation method of a polymer@cuprous oxide composite crystal particle. Amphiphilic block copolymer nanoparticles with uniform particle size distribution and good colloidal stability are synthesized by reversible addition-fragmentation chain transfer polymerization-mediated polymerization-induced self-assembly. Then, the block copolymer nanoparticles are used as additives, and polymer@cuprous oxide composite crystal particles are in-situ synthesized by hydrothermal reaction.

[0028] Specifically: The block copolymer nanoparticles are dispersed in a precursor solution and mixed evenly, and then heated to form polymer@cuprous oxide composite crystal particles. The precursor solution is a mixed solution of copper sulfate, potassium hydroxide, ammonia water, and D-(+)-glucose.

[0029] The preparation process of the polymer@cuprous oxide composite crystal particles is as follows: Set the rotation speed to 300 - 500 rpm. Add potassium hydroxide solution to the copper sulfate solution. After 1 - 10 minutes, add the block copolymer nanoparticle dispersion. Subsequently, add ammonia water and D-(+)-glucose solution in sequence, and continue stirring for 1 - 20 minutes. Then react under the condition of an oil bath at 40 - 60 °C for 3 - 12 h without stirring. After the reaction, centrifuge and wash three times with water to obtain the polymer@cuprous oxide composite crystal particles.

[0030] Among them, the volume ratio of the copper sulfate solution, potassium hydroxide solution, block copolymer nanoparticle dispersion, ammonia water, and D-(+)-glucose solution is 1200:60 - 600:1 - 60:1 - 20:60 - 600. The concentration of the copper sulfate solution is 0.01 - 0.5 mol / L, the concentration of the potassium hydroxide solution is 0.5 - 5 mol / L, the concentration of the block copolymer nanoparticles is 5 - 20%, w / w, the concentration of ammonia water is 5% - 28%, w / w, and the concentration of the D-(+)-glucose solution is 0.1 - 5 mol / L.

[0031] Furthermore, the block copolymer nanoparticles are synthesized by a polymerization-induced self-assembly method mediated by reversible addition-fragmentation chain transfer polymerization. The preparation process is as follows: Dissolve the macromolecular chain transfer agent and the initiator in the solvent, and then add the monomer. After purging with an inert gas to remove oxygen, heat and stir to polymerize to form block copolymer nanoparticles.

[0032] The macromolecular chain transfer agent is poly(glycerol methacrylate) modified with a single-terminal dithioester, the initiator is an azo initiator such as 4,4'-azobis(4-cyanovaleric acid), and the monomer is a methacrylate such as benzyl methacrylate.

[0033] Furthermore, the molar ratio of the macromolecular chain transfer agent, initiator, and monomer is 1:5:50 - 500, the solvent is water, and the ratio of the total mass of the macromolecular chain transfer agent, initiator, and monomer to the mass of the solvent is 1:4 - 19. Purge with an inert gas (such as nitrogen) in an ice-water bath to remove oxygen for 15 - 25 min, and then react in an oil bath at 50 - 70 °C for 12 - 36 h with a stirring speed of 500 - 650 rpm.

[0034] The following further elaborates the present invention with specific examples.

[0035] Example 1

[0036] The preparation process of the block copolymer nanoparticles is as follows:

[0037] Add 167.8 mg of poly(glycerol methacrylate) 51A macromolecular chain transfer agent, 1.1 mg of 4,4'-azobis(4-cyanovaleric acid), and 4.7 g of deionized water were added to a 10 mL round-bottom flask equipped with a magnetic stir bar. After the solids in the flask were completely dissolved, 352.4 mg of benzyl methacrylate was added. The flask was sealed with a rubber stopper, and nitrogen gas was introduced into the flask in an ice-water bath for 20 min to remove oxygen. Then, the flask was placed in an oil bath at 70 °C and reacted for 24 h with a stirring speed of 650 rpm. After the reaction was completed, the flask was immersed in an ice-water bath and exposed to air to quench the reaction, and finally block copolymer nanoparticles poly(glycerol methacrylate) 51 -poly(benzyl methacrylate) 100 were obtained, and its transmission electron micrograph is shown as Figure 1 below, with an average diameter of about 30 nm.

[0038] Example 2

[0039] The preparation process of pure cuprous oxide crystal particles was as follows:

[0040] The rotation speed was set at 400 rpm. 24 mL of 0.0125 mol / L copper sulfate solution was added to a 75 mL round-bottom flask equipped with a magnetic stir bar, and then 3 mL of 0.8 mol / L potassium hydroxide solution was added. After 2 minutes, 0.06 mL of 12.5%, w / w ammonia water and 3 mL of 0.158 mol / L D-(+)-glucose solution were added in sequence, and stirring was continued for 5 minutes. The reaction was carried out in an oil bath at 40 °C for 3 h without stirring. After the reaction was completed, it was centrifuged and washed three times in water to obtain pure cuprous oxide crystal particles. The low-magnification scanning electron micrograph of the crystal particles and the scanning electron micrograph of the cross-section of a single pure cuprous oxide crystal obtained after argon ion milling are shown as Figure 2 below, and the crystal particle size is 2 - 10 μm.

[0041] Example 3

[0042] The preparation process of polymer@cuprous oxide composite crystal particles was as follows:

[0043] Set the rotation speed to 400 rpm. Add 24 mL of 0.0125 mol / L copper sulfate solution to a 75 mL round-bottom flask equipped with a magnetic stir bar, and then add 3 mL of 0.8 mol / L potassium hydroxide solution. After 2 minutes, add 0.3 mL of 10%, w / w block copolymer nanoparticle dispersion (the concentration of nanoparticles in the whole system is 0.1%, w / w), and then sequentially add 0.06 mL of 12.5%, w / w ammonia water and 3 mL of 0.158 mol / L D-(+)-glucose solution, and continue stirring for 5 minutes. React for 3 h under the condition of a 40 °C oil bath without stirring. After the reaction is completed, centrifuge and wash three times with water to obtain polymer@cuprous oxide composite crystal particles. The low-magnification scanning electron microscope photograph and the scanning electron microscope photograph of the cross-section of a single polymer@cuprous oxide composite crystal obtained after argon ion milling are as shown in Figure 3 shown, and the size of the composite crystal particles is 1 - 4 μm.

[0044] Example 4

[0045] The preparation process of the polymer@cuprous oxide composite crystal particles is as follows:

[0046] Set the rotation speed to 400 rpm. Add 24 mL of 0.0125 mol / L copper sulfate solution to a 75 mL round-bottom flask equipped with a magnetic stir bar, and then add 3 mL of 0.8 mol / L potassium hydroxide solution. After 2 minutes, add 0.61 mL of 10%, w / w block copolymer nanoparticle dispersion (the concentration of nanoparticles in the whole system is 0.2%, w / w), and then sequentially add 0.06 mL of 12.5%, w / w ammonia water and 3 mL of 0.158 mol / L D-(+)-glucose solution, and continue stirring for 5 minutes. React for 3 h under the condition of a 40 °C oil bath without stirring. After the reaction is completed, centrifuge and wash three times with water to obtain polymer@cuprous oxide composite crystal particles. The low-magnification scanning electron microscope photograph and the scanning electron microscope photograph of the cross-section of a single polymer@cuprous oxide composite crystal obtained after argon ion milling are as shown in Figure 4 shown, and the size of the composite crystal particles is 1 - 3 μm.

[0047] Example 5

[0048] The test process of electron paramagnetic resonance spectroscopy is as follows:

[0049] Respectively take 35 mg of the pure cuprous oxide crystal particles prepared in Example 2 and the polymer@cuprous oxide crystal particles prepared in Example 3 and Example 4 and place them in a standard quartz tube with an outer diameter of 5 mm, and set the microwave power to 10 mW. The results are shown in Figure 5As shown, it indicates that the polymer@cuprous oxide composite crystal particles have obvious oxygen vacancy signals, and it is found by analyzing the spectrogram that the oxygen vacancy concentration increases with the increase of the concentration of block copolymer nanoparticles.

[0050] The embodiments described above are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A polymer@cuprous oxide composite crystal particle, characterized in that: The composite crystal particles use polymer nanoparticles as guest particles and cuprous oxide as host crystals, so that the guest particles are dispersed in the host crystals to form polymer@cuprous oxide composite crystal particles.

2. The polymer@cuprous oxide composite crystal particles according to claim 1, characterized in that: The guest nanoparticles are block copolymer nanoparticles or polymer surface-modified nanoparticles, and the particle size thereof is 5 to 200 nm. The size of the polymer@cuprous oxide composite crystal particles is 0.2 to 100.0 μm.

3. A method for preparing polymer@cuprous oxide composite crystal particles, characterized in that: The polymer nanoparticles are dispersed in a cuprous oxide precursor solution, mixed evenly, and heated to form polymer@cuprous oxide composite crystal particles; the polymer nanoparticles are block copolymer nanoparticles or polymer surface-modified nanoparticles; the cuprous oxide precursor solution is a mixed solution of copper sulfate, potassium hydroxide, ammonia water, and D-(+)-glucose.

4. The preparation method according to claim 3, characterized in that: The preparation process of the polymer@cuprous oxide composite crystal particles is as follows: adding a potassium hydroxide solution to a copper sulfate solution at 300-500 rpm, adding a polymer nanoparticle dispersion after 1-10 minutes, and then adding ammonia water and D-(+)-glucose solution in sequence, and continuing to stir; then reacting under oil bath conditions without stirring; and after the reaction is completed, centrifuging and washing in water to obtain the polymer@cuprous oxide composite crystal particles.

5. The preparation method according to claim 4, characterized in that: The volume ratio of the copper sulfate solution, the potassium hydroxide solution, the polymer nanoparticle dispersion, the ammonia water and the D-(+)-glucose solution is 1200:60-600:1-60:1-20:60-600.

6. The preparation method according to claim 4 or 5, characterized in that: The concentration of the copper sulfate solution is 0.01-0.5 mol / L, the concentration of the potassium hydroxide solution is 0.5-5 mol / L, the concentration of the polymer nanoparticles is 5-20%, w / w, the concentration of the ammonia water is 5%-28%, w / w, and the concentration of the D-(+)-glucose solution is 0.1-5 mol / L.

7. The preparation method according to claim 3 or 4, characterized in that: The preparation process of the polymer nanoparticles is as follows: adding a macromolecular chain transfer agent and an initiator into a solvent to dissolve them, and then adding a monomer; introducing an inert gas to remove oxygen, heating and stirring, and polymerizing to form block copolymer nanoparticles; The macromolecular chain transfer agent is polymethacrylate modified with single-end dithioester, the initiator is an azo initiator, and the monomer is methacrylate.

8. The preparation method according to claim 7, characterized in that: The molar ratio of the macromolecular chain transfer agent, the initiator and the monomer is 1:5:50-500, the solvent is water, and the ratio of the total mass of the macromolecular chain transfer agent and the monomer to the mass of the solvent is 1:4-19.

9. The preparation method according to claim 7, characterized in that: Inert gas is introduced into an ice-water bath to deoxygenate for 15 to 25 minutes, and then the mixture is reacted in an oil bath at 50 to 70°C for 12 to 36 hours with a stirring speed of 500 to 650 rpm.

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