A method for preparing high-entropy alloy based on laser-induced localized surface plasmon resonance effect

Abstract

The application discloses a method for preparing high-entropy alloy based on laser-induced local surface plasmon resonance effect. 2+ , Pd 2+ , Ru 3+ , Rh 3+ , Ir 3+ salt solution; then, the colloid and the noble metal ion salt are thoroughly mixed and uniformly distributed by using ultrasonic and magnetic stirring; finally, the uniformly mixed solution is irradiated by using a modulated 532nm waveband nanosecond pulse laser for 20 minutes, and gold-based high-entropy alloy single-crystal nanoparticles with uniform size can be obtained. The gold colloid and the reduced Pt, Pd and other metals rapidly nucleate and crystallize to generate high-entropy alloy under the promotion of configuration entropy.

Description

Technical Field

[0001] This invention relates to a novel method for preparing high-entropy alloys, and more particularly to a method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect. Background Technology

[0002] High-entropy alloys have attracted widespread attention in applications such as electrocatalysis, thermocatalysis, and clean energy conversion due to their unique microstructure, good thermal stability, and excellent catalytic activity for various reactions.

[0003] High-entropy alloys (HEAs) are an emerging material system in the current technology field. Their unique composition and structure endow them with many excellent physical and chemical properties. HEAs are typically composed of five or more elements, with each element accounting for 5% to 35% of the total molar ratio. Compared to traditional single-element or binary alloys, HEAs have higher melting points, hardness, strength, and toughness, as well as better corrosion resistance and thermal stability. These characteristics make HEAs a promising material for applications in high-temperature, high-pressure, highly corrosive, and high-load environments, such as aerospace, energy, chemical, medical device, and electronics fields. However, HEAs also present some challenges and limitations, such as the selection, proportion, and uniformity of alloying elements, the difficulty and cost of the alloying process, and the control and adjustment of microstructure.

[0004] Each element in a high-entropy alloy possesses different physicochemical properties, and traditional synthesis methods (wet chemical methods, electrochemical methods, high-temperature pyrolysis methods, etc.) easily lead to phase separation during nucleation and growth. To overcome thermodynamic limitations, the nucleation and growth of each component in the alloy must be kinetically controlled.

[0005] like Figure 1 As shown, the synthesis strategy summarized from the kinetic simulation of multi-component nucleation and growth is to synthesize high-entropy alloys through rapid heating and cooling of the raw materials. Currently, the most mature preparation method is the two-step carbothermal shock method. Its process flow is as follows: First, under argon protection, polypropylene fibers are carbonized at 800℃ for two hours to obtain the required carbon nanotubes; then, the carbon nanotubes are thoroughly impregnated with the required metal ion salt solution and dried; subsequently, the dried carbon nanotubes are connected to electrodes at both ends on a glass slide, and after high-voltage electrical treatment, the carbon nanotubes and the adsorbed metal ion salt are rapidly heated to 2000K within 5ms, rapidly generating a molten metal alloy through a carbothermal reaction. After holding at this temperature for 55ms, the alloy is rapidly cooled by air at a cooling rate of 105K / s, preventing the growth and phase separation of the alloy nanoparticles loaded on the carbon nanotubes. Other methods include nanodroplet dielectric deposition, fast moving bed pyrolysis, and polyol methods.

[0006] Currently reported methods for synthesizing high-entropy alloys generally suffer from serious problems such as complex and dangerous operation steps, long reaction time, harsh reaction conditions, and surfactant contamination.

[0007] In view of this, the present invention is hereby proposed. Summary of the Invention

[0008] The purpose of this invention is to provide a method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect, so as to solve the above-mentioned technical problems existing in the prior art.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] The method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect of the present invention includes:

[0011] First, different volumes of 1mM-10mM gold colloidal aqueous solution were placed in a quartz container, and then different volumes of 5-15mg / mL metal ion salt solution were added sequentially. The choice of concentration and volume is related to the element content distribution in the final product.

[0012] Then, ultrasonic and magnetic stirring are used to thoroughly mix the colloid and the metal ion salt.

[0013] Finally, the mixed solution was uniformly irradiated with a modulated 532nm nanosecond pulse laser for 20 minutes to obtain uniformly sized gold-based high-entropy alloy single-crystal nanoparticles.

[0014] Compared with the prior art, the present invention provides a method for preparing high-entropy alloys based on laser-induced local surface plasmon resonance effect. The present invention can prepare monodisperse gold-based high-entropy alloys in one step by irradiating a gold nanocolloid with a series of metal ion salt mixed solutions with a 532nm nanosecond pulsed laser.

[0015] This method, for the first time, utilizes the unique localized surface plasmon resonance effect of gold nanoparticles and the rapid heating and quenching characteristics of liquid-phase lasers to easily and quickly prepare a series of gold-based high-entropy alloys. Attached Figure Description

[0016] Figure 1 A schematic diagram of the kinetics simulation of nucleation and growth of multi-component alloys;

[0017] Figure 2 This is a schematic diagram of the synthesis of gold-based high-entropy alloys according to an embodiment of the present invention;

[0018] Figure 3 The TEM image of the gold-based high-entropy alloy is shown in the embodiment of the present invention.

[0019] Figure 4The XRD pattern of a face-centered cubic single crystal of a gold-based high-entropy alloy according to an embodiment of the present invention is shown.

[0020] Figure 5 This is an EDS analysis spectrum of a gold-based high-entropy alloy according to an embodiment of the present invention. Detailed Implementation

[0021] 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.

[0022] First, the following explanations are provided for the terms that may be used in this article:

[0023] 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".

[0024] 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.

[0025] The method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect of the present invention includes:

[0026] First, different volumes of 1mM-10mM gold colloidal aqueous solution were placed in a quartz container, and then different volumes of 5-15mg / mL metal ion salt solution were added sequentially. The choice of concentration and volume is related to the element content distribution in the final product.

[0027] Then, ultrasonic and magnetic stirring are used to thoroughly mix the colloid and the metal ion salt.

[0028] Finally, the mixed solution was uniformly irradiated with a modulated 532nm nanosecond pulse laser for 20 minutes to obtain uniformly sized gold-based high-entropy alloy single-crystal nanoparticles.

[0029] The metal ion salt solution includes Cu 2+ Ag + Pt 2+ Pd 2+ Ru 3+ ,Rh 3+ Ir3+ etc. solution.

[0030] In summary, the method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance (LSPR) of this invention is the first to utilize the reduction effect generated by the thermionic excitation of gold nanoparticles induced by a specific wavelength (532 nm) pulsed laser, as well as the localized high temperature generated by photo-acoustic coupling. This allows the gold nanoparticles to not only reduce Cu through the excited thermionic electrons, but also... 2+ Ag + Pt 2+ Pd 2+ Ru 3+ ,Rh 3+ Ir 3+ Metal ions, etc. At the same time, the high temperature of the molten metal combined with the rapid quenching environment provided by the liquid medium (an ideal environment for the formation of high-entropy alloys) allows the gold colloid and metals such as Pt and Pd produced by reduction to rapidly nucleate and crystallize under the promoting effect of configuration entropy, forming high-entropy alloys.

[0031] A novel and efficient method for preparing high-entropy alloys has been developed at room temperature and pressure, relying solely on laser-induced physicochemical reactions within the nanoparticles themselves. Utilizing the unique localized surface plasmon resonance properties of gold nanoparticles, a specific wavelength (532 nm) laser irradiates a colloidal gold nanoparticle solution. Simultaneously, the thermal electrons induction reduces metal ions in the colloidal solution, while the photo-acoustic coupling effect between the light and the metal particles rapidly heats and melts the gold nanoparticles with the reduced metal elements, resulting in alloying. The liquid medium facilitates a faster quenching effect than air, and kinetically controlled processes prevent particle growth and phase separation. Since the experimental process only requires laser irradiation of a mixture of gold colloidal particles and metal ion salts, the high-temperature and high-pressure physicochemical reactions occur within the localized area of ​​the nanoparticles. The operating environment remains at room temperature and pressure, ensuring operator safety and ensuring simple and reliable operation. Furthermore, the reaction process avoids the introduction of surfactants such as oleic acid and oleylamine, making it more environmentally friendly.

[0032] This invention expands the ideas for preparing novel materials by combining nanosecond pulsed lasers with material properties, and also provides a new path for the preparation of high-entropy alloys.

[0033] 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.

[0034] Example 1

[0035] A schematic diagram of the specific synthesis of gold-based high-entropy alloys is shown below. Figure 2 As shown: A gold colloidal aqueous solution of appropriate concentration was placed in a quartz container, followed by the addition of metal ion salts of appropriate concentrations (Pt).2+ Pd 2+ Ru 3+ ,Rh 3+ Ir 3+ The solution (e.g., gold colloid and metal ion salt) is thoroughly mixed using ultrasound and magnetic stirring. Finally, the homogeneous mixture is irradiated with a modulated 532nm nanosecond pulsed laser for 20 minutes to obtain gold-based high-entropy alloy single-crystal nanoparticles with relatively uniform size.

[0036] The present invention relates to a simple and rapid one-step experiment for preparing high-entropy alloys, and the entire preparation process is clean and efficient. It fully combines the technical characteristics of liquid-phase laser irradiation, the unique physical properties of gold nanoparticles, and the preparation conditions required for the synthesis of high-entropy alloys.

[0037] To identify the product, the sample was first analyzed by transmission electron microscopy (TEM), and the results showed that... Figure 3 The sample exhibits a grape-like shape, with small particles assembled together, and the size is relatively uniform. High-resolution lattice analysis shows that the particles are in the form of metallic single crystals.

[0038] The sample was then analyzed by powder X-ray diffraction (XRD), such as... Figure 4 As shown, the sample is matched with a face-centered cubic (FCC) single crystal of Pt group noble metals. Due to the single crystal solid solution formed by the doping of multiple elements, some lattices are slightly shifted.

[0039] In addition, another option is to select Figure 3 Nanoparticles in TEM were subjected to X-ray energy dispersive spectroscopy (EDS) analysis. Figure 5 It was found that elements such as Au, Pt, Pd, Ru, and Ir were uniformly distributed in the formed single-crystal particles. This proves that the gold-based high-entropy single-crystal solid solution alloy with uniform element distribution was successfully prepared through the experiment designed in this invention.

[0040] This invention provides a novel, green, simple, and efficient method for preparing high-entropy alloys. Utilizing the localized surface plasmon resonance effect of gold nanoparticles under 532nm wavelength light induction, this invention, for the first time, uses a 532nm nanosecond pulsed laser to irradiate a mixed solution of gold colloid and metal ion salt, resulting in a one-step preparation of high-entropy alloys with relatively uniform size and clean surfaces. The entire experiment is conducted at room temperature and pressure, ensuring simple and safe operation; furthermore, it eliminates the need for end-capping agents, surfactants, or other environmentally friendly substances. The resulting high-entropy alloy exhibits stable properties, small size, large specific surface area, and is free from end-capping agent interference. Moreover, the elemental ratio of the final product can be effectively adjusted by changing the concentrations of gold colloid and metal ion salt, demonstrating exceptional surface activity and physical stability. This method holds promise for applications in electrocatalysis, biology, and mechanics. It enriches the application range of liquid-phase laser processing technology for preparing novel materials and further expands the synthetic ideas for high-entropy alloys.

[0041] 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 preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect, characterized in that, include: First, different volumes of 1mM-10mM gold colloidal aqueous solution were placed in a quartz container, and then different volumes of 5-15mg / mL metal ion salt solution were added sequentially. The choice of concentration and volume is related to the element content distribution in the final product. Then, ultrasonic and magnetic stirring are used to thoroughly mix the gold colloid with the metal ion salt. Finally, the mixed solution was uniformly irradiated with a modulated 532nm nanosecond pulse laser for 20 minutes to obtain uniformly sized gold-based high-entropy alloy single-crystal nanoparticles.

2. The method for preparing high-entropy alloys based on laser-induced localized surface plasmon resonance effect according to claim 1, characterized in that, The metal ion salt solution includes Cu 2+ Ag + Pt 2+ Pd 2+ Ru 3+ ,Rh 3+ Ir 3+ Solution.

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