A method for supporting small-size noble metals on a molybdenum carbide carrier

Abstract

The application discloses a kind of liquid-phase laser preparation methods of molybdenum carbide carrier load metal composite material, first based on liquid-phase pulse laser ablation technology in acetone ablation elemental Ag or Au target material, obtain the Ag or Au nanoparticle of uniform dispersion with 1-2 layers carbon layer coating, the process metal nanoparticle size distribution is uniform and adjustable.Then utilize pulse laser irradiation technology to make oxide MoO3 powder in high carbon reduction liquid phase environment (acetone) in situ carbonization change into MoC nanoparticle.Finally, using 355nm wavelength laser irradiation metal nanoparticle and MoC mixed liquid can prepare Ag@MoC or Au@MoC etc. series composite materials.The method improves the traditional metal doped molybdenum carbide process, without adding any other surfactant, stabilizer and other chemical reagents, avoid the generation of other impurity products.Operation is simple, green and efficient, and strong universality.

Description

Technical Field

[0001] This invention relates to a technique for preparing composite materials by doping / loading noble metals with molybdenum carbide, and more particularly to a method for loading small-sized noble metals onto a molybdenum carbide carrier. Background Technology

[0002] Molybdenum carbide (MoCb), as a non-precious metal material, has attracted widespread attention due to its good biocompatibility, photothermal tumor therapeutic efficacy, and excellent catalytic activity. MoCb can modify its catalytic behavior by adjusting the charge density of the supported metal. Doping MoCb with metal elements can improve its microwave absorption properties. To meet the diverse application requirements of MoCb, doping and defect engineering techniques are often used to develop MoCb-based composite materials.

[0003] Currently, the preparation of molybdenum carbide-doped / loaded noble metal composites generally employs high-temperature sintering. However, this method results in molybdenum carbide-based composites that are prone to aggregation and exhibit uneven distribution of the loaded metal particles. Furthermore, the use of various chemical reagents during the experiments inevitably leads to residual impurities, and the process is complex, cumbersome, and potentially dangerous.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a method for loading small-sized noble metals onto a molybdenum carbide support, so as to solve the above-mentioned technical problems existing in the prior art.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] The method for loading small-sized noble metals onto a molybdenum carbide support according to the present invention includes the following steps:

[0008] Step 1) First, based on liquid phase laser ablation technology, elemental Ag, Au, or Pt target material is ablated in 20 mL of acetone to obtain a uniformly dispersed colloidal solution of Ag, Au, or Pt nanoparticles coated with 1 to 2 carbon layers.

[0009] Step 2) Then, using pulsed laser irradiation technology, 1 mg of MoO3 powder is carbonized in situ in a 10 mL acetone or ethanol liquid environment to transform it into a colloidal solution containing MoC nanoparticles.

[0010] Step 3) Finally, the obtained colloidal solution containing Ag, Au, or Pt nanoparticles is mixed with the colloidal solution containing MoC nanoparticles and ultrasonically treated. Then, it is irradiated with a laser with a wavelength of 355nm for 20 minutes to prepare Ag@MoC, Au@MoC, or Pt@MoC series composite materials.

[0011] Compared with existing technologies, the method for loading small-sized noble metals onto molybdenum carbide supports provided by this invention utilizes the instantaneous high-temperature and high-pressure effect generated by laser to load metal particles onto the molybdenum carbide support in situ. It eliminates the need for stabilizers, surfactants, and other chemical reagents, making the operation simple, green, and efficient. Furthermore, the size of the loaded noble metal particles is adjustable and their distribution is uniform. This method provides a new approach and concept for the preparation and application of noble metal nanoparticles loaded onto molybdenum carbide supports. The noble metals involved include Au, Ag, and Pt, and the carbon supports include molybdenum carbide and graphene. The method process is described in detail using Ag@MoC and Au@MoC composite materials as examples. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart illustrating the preparation of ultra-small noble metal nanocomposites on a molybdenum carbide support based on liquid phase laser technology in an embodiment of the present invention.

[0014] Figure 2 The TEM images and elemental distribution diagrams of Ag@MoC(a) and Au@MoC(b) in the embodiments of the present invention are shown.

[0015] Figure 3 The images show XRD patterns of light absorption of Ag@MoC (a) and (c) and light absorption of Au@MoC (b) and (d) in embodiments of the present invention.

[0016] Figure 4 The temperature-time curves of different concentrations of Ag@MoC under 808nm laser irradiation within 10 min are shown in (a) in this embodiment of the invention. The antibacterial performance of Ag@MoC against two bacteria (E. coil and S. aureus) was evaluated over different time periods (0, 10, 30 min) (b). Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them, and do not constitute a limitation on the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0018] First, the following explanations are provided for the terms that may be used in this article:

[0019] The term "and / or" means that either or both can be achieved simultaneously. For example, X and / or Y means that it includes both "X" or "Y" as well as the three cases of "X and Y".

[0020] The terms “including,” “contains,” “comprising,” “having,” or other similar semantic descriptions shall be interpreted as non-exclusive inclusion.

[0021] The contents not described in detail in the embodiments of this invention are prior art known to those skilled in the art. Where specific conditions are not specified in the embodiments of this invention, they shall be performed according to conventional conditions in the art or conditions recommended by the manufacturer. Where the manufacturers of the reagents or instruments used in the embodiments of this invention are not specified, they are all conventional products that can be purchased commercially.

[0022] The method for loading small-sized noble metals onto a molybdenum carbide support according to the present invention includes the following steps:

[0023] Step 1) First, based on liquid phase laser ablation technology, elemental Ag, Au, or Pt target material is ablated in 20 mL of acetone to obtain a uniformly dispersed colloidal solution of Ag, Au, or Pt nanoparticles coated with 1 to 2 carbon layers.

[0024] Step 2) Then, using pulsed laser irradiation technology, 1 mg of MoO3 powder is carbonized in situ in a 10 mL acetone or ethanol liquid environment to transform it into a colloidal solution containing MoC nanoparticles.

[0025] Step 3) Finally, the obtained colloidal solution containing Ag, Au, or Pt nanoparticles is mixed with the colloidal solution containing MoC nanoparticles and ultrasonically treated. Then, it is irradiated with a laser with a wavelength of 355nm for 20 minutes to prepare Ag@MoC, Au@MoC, or Pt@MoC series composite materials.

[0026] In step 1), the metal target is dissolved in acetone or ethanol at a laser wavelength of 1064nm or 532nm, resulting in metal nanoparticles with uniform and adjustable size distribution.

[0027] Step 2) involves ultrasonically dispersing the MO3 powder in acetone or ethanol.

[0028] Step 3) involves a laser wavelength of 355nm and an irradiation time of 20min.

[0029] The preparation process requires no high-temperature environment, no inert gas protection, and no addition of surfactants or stabilizers.

[0030] This invention first utilizes liquid-phase laser ablation technology to ablate elemental Ag or Au targets in acetone, obtaining uniformly dispersed Ag or Au nanoparticles coated with 1-2 carbon layers. This process results in a uniform and tunable size distribution of the metal nanoparticles. Then, pulsed laser irradiation is used to in-situ carbonize MoO3 oxide powder into MoC nanoparticles in a high-carbon reducing liquid environment (acetone). Finally, laser irradiation of the mixture of metal nanoparticles and MoC yields a series of composite materials such as Ag@MoC or Au@MoC. This method improves upon traditional metal-doped molybdenum carbide processes, eliminating the need for any additional surfactants, stabilizers, or other chemical reagents, thus avoiding the formation of other impurity products. It also eliminates the need for prolonged high-temperature heat treatment, preventing the agglomeration of metal nanoparticles. The loaded metal particles have tunable and uniform particle size distribution, promising potential in catalysis and biology. Furthermore, this method is simple to operate, green, efficient, and widely applicable. This not only provides a new approach and idea for the preparation and application of small-sized, highly dispersed noble metal loads on molybdenum carbide-supported nanocomposites, but also expands new applications of liquid phase laser irradiation technology.

[0031] In summary, the method for loading small-sized noble metals onto a molybdenum carbide support in this invention utilizes liquid-phase laser irradiation of a mixed solution of metal nanoparticles and molybdenum carbide to directly obtain molybdenum carbide-based composite materials with uniformly distributed sizes of different metal loads. During laser irradiation, the molybdenum carbide support absorbs light energy and generates localized high temperature and pressure, directly loading metal nanoparticles with 1-2 carbon layers onto the molybdenum carbide support. This invention expands the application of liquid-phase laser preparation technology in materials synthesis and provides new avenues and bases for in-depth research on molybdenum carbide-based nanocomposites and their applications. It is a novel method for molybdenum carbide-based loaded metal nanoparticle composite materials.

[0032] To more clearly demonstrate the technical solution and its effects provided by the present invention, the embodiments of the present invention will be described in detail below with reference to specific examples.

[0033] Example 1

[0034] The specific experimental procedure is as follows Figure 1 As shown:

[0035] First, a 532 nm wavelength laser with an output energy of 90 mJ / pulse was used to ablate a pure Ag target in 20 mL of acetone for 20 min, obtaining uniformly dispersed Ag nanoparticles coated with 1-2 carbon layers. Then, a 532 nm wavelength pulsed laser with an output energy of 200 mJ / pulse was used to in-situ carbonize 1 mg of MoO3 oxide powder in 10 mL of acetone, transforming it into a MoC-containing nanoparticle colloidal solution. Finally, the Ag@MoC composite material was prepared by irradiating the ultrasonically treated Ag nanoparticle and MoC mixture with a 355 nm wavelength laser for 20 min.

[0036] Example 2

[0037] The specific experimental procedure is as follows Figure 1 As shown:

[0038] First, a 532 nm wavelength laser with an output energy of 90 mJ / pulse was used to ablate a pure Au target in 20 mL of acetone for 20 min, obtaining a uniformly dispersed Au nanoparticle colloid coated with 1-2 carbon layers. Then, a 532 nm wavelength pulsed laser with an output energy of 200 mJ / pulse was used to in-situ carbonize 1 mg of MoO3 oxide powder in 10 mL of acetone, transforming it into a MoC-containing nanoparticle colloidal solution. Finally, the Au@MoC composite material was prepared by irradiating the ultrasonically treated Au nanoparticle and MoC mixture with a 355 nm wavelength laser for 20 min.

[0039] Morphology and performance testing

[0040] The Ag@MoC composite material prepared in Example 1 of the present invention and the Au@MoC composite material prepared in Example 2 of the present invention were subjected to the following morphological and performance tests:

[0041] (1) To characterize the morphology of the products of Examples 1 and 2 of the present invention, the Ag@MoC composite material prepared in Example 1 and the Au@MoC composite material prepared in Example 2 of the present invention were observed by transmission electron microscopy, respectively. Figure 2 As shown, Ag or Au nanoparticles are uniformly distributed on the MoC support. Such a unique structural material may exhibit special properties in catalysis and biological fields.

[0042] (2) In order to further determine the formation and phase of the products of Example 1 and Example 2 of the present invention, light absorption and XRD tests were performed on the Ag@MoC composite material prepared in Example 1 of the present invention and the Au@MoC composite material prepared in Example 2 of the present invention, respectively. Figure 3 (a) and (c) are the light absorption and XRD patterns of Ag@MoC in the embodiments of the present invention. Figure 3 (b) and (d) are the optical absorption and XRD patterns of Au@MoC. Figure 3 As can be seen from (a) and (b) in the figures, compared with the light absorption spectra of MoC, Ag, and Au alone, the Ag@MoC nanocomposite material prepared in Example 1 of this invention exhibits an Ag ultraviolet absorption peak, and the Au@MoC nanocomposite material prepared in Example 2 of this invention exhibits an Au ultraviolet absorption peak. Figure 3 XRD patterns (c) and (d) show that the Ag@MoC nanocomposite material prepared in Example 1 of this invention exhibits both MoC and Ag phases. Similarly, the Au@MoC nanocomposite material prepared in Example 2 of this invention exhibits both MoC and Au phases. This further demonstrates that Example 1 of this invention successfully loaded small-sized Ag nanoparticles onto a MoC support, and Example 2 of this invention successfully loaded small-sized Au nanoparticles onto a MoC support. These results are consistent with the aforementioned TEM results.

[0043] (3) Some work has already been done on the application of Ag@MoC in photothermal antibacterial processes. From Figure 4 (a) It can be seen that as the concentration of Ag@MoC increases, its temperature continuously rises under 808nm laser irradiation, reaching a maximum of 45℃. Ag@MoC exhibits excellent photothermal conversion capabilities. Heat treatment can cause bacterial cell membrane rupture, thereby exerting an antibacterial effect. Figure 4 (b) It can be seen that, compared with the control group, the survival rate of the two bacteria (E. coli and S. aureus) was significantly reduced after Ag@MoC was irradiated with 808 nm near-infrared light for different durations, indicating that Ag@MoC has excellent photothermal synergistic antibacterial ability. The silver ions (Ag) released by Ag nanoparticles... + Ag plays an important role in killing bacteria. However, the uncontrolled release of Ag from pure Ag nanoparticles... + Ions can cause severe cytotoxicity and resource waste. Therefore, loading Ag nanoparticles onto a MoC support can reduce the amount of Ag used and... + Ion release is controllable. Moreover, the ultra-small noble metal nanocomposites loaded on the molybdenum carbide support prepared by this method do not contain other harmful chemical reagents, and have great application potential in the biological field.

[0044] In summary, the embodiments of the present invention can not only achieve the loading of metal nanoparticles on molybdenum carbide supports, but also these metal nanoparticles have the advantages of adjustable size and uniform dispersion. The preparation process is easy to operate, low in cost, and does not require the addition of any surfactants and stabilizers, nor does it require high temperature and inert gas protection. It has good application prospects in the fields of biology and catalysis.

[0045] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims. The information disclosed in the background section is intended only to enhance the understanding of the overall background technology of the present invention and should not be construed as an admission or implication in any way that such information constitutes prior art known to those skilled in the art.

Claims

1. A method for loading small-sized noble metals onto a molybdenum carbide support, characterized in that, Including the following steps: Step 1) First, based on liquid phase laser ablation technology, elemental Ag or Au or Pt target material is ablated in 20 mL of acetone or ethanol to obtain a uniformly dispersed colloidal solution of Ag or Au or Pt nanoparticles coated with 1 to 2 carbon layers. Step 2) Then, using pulsed laser irradiation technology, 1 mg of MoO3 powder is carbonized in situ in 10 mL of acetone or ethanol liquid phase environment to transform it into a colloidal solution containing MoC nanoparticles. Step 3) Finally, the obtained colloidal solution containing Ag, Au, or Pt nanoparticles is mixed with the colloidal solution containing MoC nanoparticles and ultrasonically treated. Then, it is irradiated with a laser with a wavelength of 355nm for 20 minutes to prepare Ag@MoC, Au@MoC, or Pt@MoC series composite materials.

2. The method for loading small-sized noble metals onto a molybdenum carbide support according to claim 1, characterized in that, In step 1), the metal target is dissolved in acetone or ethanol at a laser wavelength of 1064nm or 532nm, resulting in metal nanoparticles with uniform and adjustable size distribution.

3. The method for loading small-sized noble metals onto a molybdenum carbide support according to claim 1, characterized in that, Step 2) involves ultrasonically dispersing MoO3 powder in acetone or ethanol.

4. The method for loading small-sized noble metals onto a molybdenum carbide support according to any one of claims 1 to 3, characterized in that, The preparation process requires no high-temperature environment, no inert gas protection, and no addition of surfactants or stabilizers.

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