Preparation method of mesoporous amorphous alloy film
By combining electrochemical deposition with autocatalytic chemical reduction, the problem of uneven pore size and distribution in mesoporous amorphous alloy films was solved, achieving efficient preparation of mesoporous structures and improving catalytic performance and material reproducibility.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XI AN JIAOTONG UNIV
- Filing Date
- 2026-05-09
- Publication Date
- 2026-06-19
AI Technical Summary
In existing technologies, the pore size and distribution of mesoporous amorphous alloy films prepared by chemical reduction methods are uneven and difficult to control precisely, resulting in uneven pore distribution in the alloy films and affecting their performance in the field of electrochemical catalysis.
A combination of electrochemical deposition and autocatalytic chemical reduction was employed to nucleate and form a regular template in the gaps between polymer micelles using an electric field. By combining linear voltammetric scanning and autocatalytic chemical deposition, mesoporous amorphous alloy films were prepared. Metal atoms were induced to grow mildly and controllably on the initial framework through electrodeposition, forming a uniform mesoporous structure.
The controllable synthesis of mesoporous amorphous alloy films with uniform pore size and consistent three-dimensional porosity was achieved, which improved the active sites and electron migration rate of electrochemical reactions, and enhanced catalytic performance and material reproducibility.
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Figure CN122235754A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of metal thin film technology, and in particular to a method for preparing mesoporous amorphous alloy thin films. Background Technology
[0002] Two-dimensional (2D) mesoporous metal films combine high specific surface area, efficient mass transfer channels, and excellent conductivity, making them promising candidates for electrocatalysis. The fixed atomic arrangement of traditional crystalline alloys limits the number of active sites and electron transfer. In contrast, the short-range ordered / long-range disordered structure of amorphous alloys provides a more flexible electronic structure and disordered atomic arrangement, offering more active sites, lowering reaction barriers, and enhancing corrosion resistance. Iron group (Ni, Co, Fe) amorphous films exhibit soft magnetic behavior, high resistivity, low coercivity, and isotropic magnetic response, making them valuable in electrochemical catalysis.
[0003] In existing technologies, chemical reduction is often used to prepare mesoporous amorphous alloy films, relying on chemical reducing agents to provide electrons for the reduction of metal ions. Some researchers have prepared porous, nodular cobalt-nickel boride electrodes by using hydrogen bubbles generated during the chemical reduction process to form pores in the material. The process involves: based on the principle of liquid-phase chemical reduction, using chemical reducing agents such as hypophosphite, borohydride, and dimethylamine borane as electron donors, inducing the reduction and precipitation of metal ions on the substrate surface through an autocatalytic reaction, accompanied by the co-deposition of metal-like elements, resulting in an alloy film with an amorphous structure.
[0004] However, the nucleation location, growth rate, and detachment timing of hydrogen bubbles generated during the chemical reduction process are difficult to control precisely, resulting in pore sizes of alloy films ranging from nanometers to micrometers, and significant differences in porosity along the film plane and thickness direction, leading to uneven pore distribution in the alloy films. Summary of the Invention
[0005] Therefore, it is necessary to provide a method for preparing mesoporous amorphous alloy thin films to address the aforementioned technical problems.
[0006] This invention provides a method for preparing mesoporous amorphous alloy thin films, comprising: A mixed solution containing polymer micelles was obtained by mixing a diblock polymer, an organic solvent, water, and a metal salt precursor; and a boron-containing reducing agent was added to the mixed solution to obtain an electrolyte. Using a Pt wire as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and a conductive substrate as the working electrode, a three-electrode system was used to perform linear voltammetric scanning in the electrolyte to perform electrodeposition on the conductive substrate and obtain an initial deposition layer. The initial deposited layer was placed in an electrolyte and allowed to stand. Autocatalytic chemical deposition was then carried out under the action of a protective gas to continue growth on the initial deposited layer, thus obtaining the initial alloy film. The initial alloy film was immersed in an organic solvent to remove polymer micelles, resulting in a mesoporous amorphous alloy film loaded on a conductive substrate.
[0007] Optionally, the diblock polymer is polystyrene-b-polyethylene oxide.
[0008] Optionally, the metal salt precursor includes nickel acetate, cobalt acetate, and ferric chloride.
[0009] Optionally, the boron-containing reducing agent is a dimethylamineborane solution.
[0010] Optionally, the potential window for linear voltammetric scanning is -0.2 V to -2.0 V relative to the saturated Ag / AgCl electrode, the scan rate is 50 mV / s to 200 mV / s, and the number of scan cycles is 2 to 10.
[0011] Optionally, the protective gas may include nitrogen or argon.
[0012] Optionally, the organic solvent is N,N-dimethylformamide.
[0013] Optionally, the conductive substrate includes: carbon paper, carbon cloth, nickel foam, copper foil, or ITO conductive glass.
[0014] Optionally, the method further includes placing the mesoporous amorphous alloy film in a tube furnace and calcining it under the action of a mixed gas including hydrogen and argon to obtain a mesoporous crystalline alloy film.
[0015] The method for preparing a mesoporous amorphous alloy thin film provided in this invention has the following advantages compared with the prior art: This invention combines electrochemical reduction and chemical reduction techniques. Electrochemical deposition, under the control of an electric field, precisely induces metal atoms to uniformly nucleate in the intercellular spaces of polymer micelles, forming an initial ordered framework with regular template sites. This establishes a regular substrate for mesoporous structures and suppresses violent hydrogen evolution side reactions. While preserving the template-confined environment, a surface-catalyzed autocatalytic chemical reduction process allows for the mild and controllable epitaxial growth of metal atoms on the active sites of the initial framework. This synergistic technique utilizes the high efficiency of electroreduction and the controllability of chemical reduction through an electrodeposition-induced autocatalytic process, achieving the controllable synthesis of mesoporous amorphous alloy films with uniform pore size and consistent three-dimensional porosity. Attached Figure Description
[0016] Figure 1 X-ray diffraction pattern of an alloy thin film according to a method for preparing a mesoporous amorphous alloy thin film provided in one embodiment; Figure 2 This is a schematic diagram of a mesoporous amorphous nickel-cobalt-iron-boron alloy thin film prepared according to a method for preparing a mesoporous amorphous alloy thin film in one embodiment. Figure 2 Image (a) is a low-magnification SEM image of a mesoporous amorphous nickel-cobalt-iron-boron alloy thin film. Figure 2 Image (b) is a SEM image of a mesoporous amorphous nickel-cobalt-iron-boron alloy thin film at medium magnification. Figure 2 (c) is a high-magnification SEM image of a mesoporous amorphous nickel-cobalt-iron-boron alloy thin film; Figure 3 The image shows the catalytic activity curve of the oxygen evolution reaction of an alloy thin film prepared by a method for preparing a mesoporous amorphous alloy thin film in one embodiment. Figure 4 The figure shows the stability test evaluation results of a method for preparing a mesoporous amorphous alloy thin film provided in one embodiment; Figure 5 This is a schematic flowchart illustrating a method for preparing a mesoporous amorphous alloy thin film in one embodiment. Detailed Implementation
[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0018] Electrolysis of water to produce hydrogen is a device that converts electrical energy into hydrogen gas for energy storage. It enables the on-site conversion and storage of surplus electrical energy, and is an effective way to solve the problem of renewable energy power consumption and ensure the stable and efficient operation of new power systems. However, the oxygen evolution reaction (OER) at the anolyte, due to its high reaction barrier and slow kinetics caused by four-electron transfer, severely restricts further improvements in the efficiency of water electrolysis devices. Designing the microstructure of the catalyst and optimizing its electronic structure is key to obtaining high-performance OER catalysts.
[0019] To synthesize high-performance two-dimensional thin film materials for electrocatalysis, researchers have induced the co-precipitation of metal ions by reacting a mixed solution containing cobalt and vanadium sources with an alkaline solution, thus synthesizing amorphous and ultrathin cobalt vanadium (hydrogen) oxide catalysts. The synergistic effect between the metals significantly improved the oxygen evolution reaction performance. However, the metals in two-dimensional mesoporous films are usually in an oxidized hydroxide state, not a metal state. Physical deposition methods (such as magnetron sputtering) and chemical vapor deposition can be used to prepare amorphous magnetic films, but due to the high-energy growth environment, these techniques have limited control over the nanostructure, making it difficult to form the desired mesoporous structure.
[0020] In contrast, electroplating (electrodeposition) is a simple and versatile chemical method that can rapidly prepare thin films under mild conditions and, when combined with polymeric micellar pore-forming agents, can introduce mesoporous structures into materials. However, this strategy is currently limited to crystalline structures and noble metals. Some researchers have synthesized a series of ternary iron-cobalt-nickel nanostructured films with different cobalt contents on indium tin oxide (ITO) glass substrates using lower negative deposition potentials. However, electroplating of iron group metals can only produce dense crystalline films without porosity.
[0021] Another method is chemical reduction (autocatalysis). Unlike electroplating, it does not require a continuous electron supply from an external DC power source. Instead, it relies on a chemical reducing agent to provide electrons for the reduction of metal ions. During this process, heteroatoms such as boron (B) or phosphorus (P) can be incorporated into the metal lattice to alter the crystal structure (e.g., amorphization) and affect performance. However, chemical reduction requires precise control of process parameters (e.g., pH, temperature, and complexing agents), and the resulting films are typically dense, non-mesoporous structures. Some researchers have prepared porous, nodular cobalt-nickel boride electrodes by utilizing the release of hydrogen during chemical reduction. The resulting microporous channels facilitate electrolyte permeation and gas expulsion, enhancing their catalytic performance. However, the resulting structures exhibit uneven pore distribution and limited compositional tunability.
[0022] This invention provides a method for preparing mesoporous amorphous alloy thin films, such as... Figure 5 As shown, the method includes: A mixed solution containing polymer micelles was obtained by mixing a diblock polymer, an organic solvent, water, and a metal salt precursor. A boron-containing reducing agent was added to the mixed solution to obtain an electrolyte. A Pt wire was used as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and a conductive substrate as the working electrode. A three-electrode system was used to perform linear voltammetry scanning in the electrolyte to electrodeposit an initial deposition layer on the conductive substrate. The initial deposition layer was then left to stand in the electrolyte and subjected to autocatalytic chemical deposition under a protective gas atmosphere to continue growth, yielding an initial alloy film. The initial alloy film was then immersed in an organic solvent to remove the polymer micelles, resulting in a mesoporous amorphous alloy film supported on the conductive substrate.
[0023] The diblock polymer is polystyrene-b-polyethylene oxide. The metal salt precursors include nickel acetate, cobalt acetate, and ferric chloride. The boron-containing reducing agent is a dimethylamine borane solution, and the organic solvent is N,N-dimethylformamide. The protective gas includes nitrogen or argon, and the conductive substrate includes carbon paper, carbon cloth, nickel foam, copper foil, or ITO conductive glass.
[0024] Preferably, the potential window for the linear voltammetric scan is -0.2 V to -2.0 V relative to the saturated Ag / AgCl electrode, the scan rate is 50 mV / s to 200 mV / s, and the number of scan cycles is 2 to 10.
[0025] Preferably, the process further includes placing the mesoporous amorphous alloy film in a tube furnace and calcining it under the action of a mixed gas including hydrogen and argon to obtain a mesoporous crystalline alloy film.
[0026] This invention combines electrochemical reduction and chemical reduction techniques to propose an amorphous nickel-cobalt-iron-boron alloy thin film with ordered mesoporous distribution and its preparation method. Furthermore, this preparation method exhibits strong applicability to various conductive substrates. In one specific embodiment, the technical solution includes the following steps:
[0027] (1) 10 mg of the diblock polymer (polystyrene-b-polyethylene oxide) was ultrasonically dissolved in 3 ml of N,N-dimethylformamide (DMF), and 3 ml of deionized water was added to form a micelle solution. In 0.15 g of (CH3CH2CH2CH2)4N(Br), nickel acetate (Ni(CH3COO)2·4H2O) solution, cobalt acetate (Co(CH3COO)2·4H2O) solution, and ferric chloride (FeCl3) solution were added in appropriate molar ratios to ensure complete dissolution. This solution was then added to the micelle solution to obtain a mixed solution containing polymer micelles. Finally, 6 ml of 0.5 mol / L dimethylaminoborane (DMAB) solution was added to the above solution to form an electrolyte solution.
[0028] (2) Electrodeposition was performed in a typical three-electrode system, with a Pt wire as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and carbon paper as the working electrode. Linear sweep voltammetry (LSV) was repeated from -0.2V to -2.0V (vs Ag / AgCl) at a scan rate of 100 mV / s, for a total of 6 cycles with a 1-minute interval between each cycle to avoid concentration differences near the electrode caused by continuous electrodeposition.
[0029] (3) The electrodeposited carbon paper is kept in the electrolyte for a certain period of time, during which nitrogen protective gas is continuously introduced above the liquid surface. Finally, the carbon paper is taken out and immersed in N,N-dimethylformamide (DMF) to remove the diblock polymer, thereby obtaining a mesoporous amorphous nickel-cobalt-iron-boron alloy film loaded on the carbon paper.
[0030] The beneficial effects achieved by this invention include, but are not limited to: (1) Synergistic construction of mesoporous structure and metallic amorphous structure.
[0031] This invention overcomes the challenge of simultaneously achieving a well-defined mesoporous network and amorphous metallic structure in iron-group alloys by combining electrodeposition and autocatalysis. Compared to existing physical deposition processes that are limited by high-temperature and high-energy environments, the mesoporous amorphous alloys prepared under mild conditions in this invention retain the metal-boron bonds and disordered atomic arrangement in the amorphous state, increasing the intrinsic active sites for electrochemical reactions and significantly improving the electron migration rate.
[0032] (2) To achieve precise quantitative control of thin film structure parameters.
[0033] Existing technologies often struggle to precisely control film thickness and composition due to the sensitivity of process conditions and the complexity of parameter coupling. This invention, by adjusting the concentration of the metal precursor and the autocatalytic growth time, enables precise control of film thickness and allows for the adjustment of compositions from binary to quaternary alloys, significantly improving the repeatability and process flexibility of material preparation.
[0034] (3) This invention has strong universality to different conductive substrates and can achieve good loading on carbon cloth, carbon paper, nickel foam, copper foil and ITO conductive glass. This broad compatibility greatly expands the application scenarios of this material in industrial fields such as energy conversion, electrochemical sensing and magnetic storage.
[0035] Example 1: A controllable synthesis strategy for electrodeposition-induced autocatalysis of mesoporous amorphous alloy thin films.
[0036] (1) Preparation of electrolyte.
[0037] 10 mg of biblock polymer PS 5000 -b-PEO 2000 The solution was ultrasonically dissolved in 3 ml of N,N-dimethylformamide (DMF), and 3 ml of deionized water was added to form a micelle solution. A 60 mmol / L aqueous solution of Co(CH3COO)2·4H2O, Ni(CH3COO)2·4H2O, and FeCl3 was prepared. Since FeCl3 is prone to hydrolysis, argon gas was continuously bubbled through the fresh FeCl3 solution to inhibit hydrolysis. 1 ml of Ni(CH3COO)2·4H2O solution, 2.2 ml of Co(CH3COO)2·4H2O solution, and 0.8 ml of FeCl3 solution were added to (CH3CH2CH2CH2)4N(Br) and allowed to dissolve completely before being added to the micelle solution. Finally, 6 ml of 0.5 mol / L DMAB solution was added to the above solution to form an electrolyte solution.
[0038] (2) Electrodeposition.
[0039] Electrodeposition was performed in a typical three-electrode system, with a Pt wire as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and carbon paper as the working electrode. Repeated LSV scans were performed at a scan rate of 100 mV / s from -0.2 V to -2.0 V (vs Ag / AgCl), for six cycles, with a one-minute interval between each cycle, to avoid concentration gradients near the electrodes caused by continuous electrodeposition.
[0040] (3) Chemical deposition.
[0041] The electrodeposited carbon paper was kept stagnant in the electrolyte for a certain period of time, during which nitrogen protective gas was continuously circulated above the liquid surface. Finally, the carbon paper was removed and immersed in DMF to remove the diblock polymer, obtaining a mesoporous amorphous alloy film a-NiCoFeB loaded on the carbon paper.
[0042] like Figure 2 As shown, the mesoporous amorphous alloy thin film a-NiCoFeB obtained in Example 1 can be uniformly deposited on the surface of carbon paper to form a distinct mesoporous structure.
[0043] Example 2: A controllable synthesis strategy for electrodeposition-induced autocatalysis of mesoporous crystalline alloy thin films.
[0044] (1) Preparation of electrolyte.
[0045] 10 mg of biblock polymer PS 5000 -b-PEO 2000 The solution was ultrasonically dissolved in 3 ml of N,N-dimethylformamide (DMF), and 3 ml of deionized water was added to form a micelle solution.
[0046] Prepare 60 mmol / L aqueous solutions of cobalt acetate (Co(CH3COO)2·4H2O), nickel acetate (Ni(CH3COO)2·4H2O), and FeCl3. Since FeCl3 is prone to hydrolysis, argon gas is continuously bubbled through the fresh FeCl3 solution to inhibit hydrolysis. Add 1 ml of nickel acetate aqueous solution (Ni(CH3COO)2·4H2O), 2.2 ml of cobalt acetate aqueous solution (Co(CH3COO)2·4H2O), and 0.8 ml of FeCl3 solution to 0.15 g of tetrabutylammonium bromide ((CH3CH2CH2CH2)4N(Br)) until fully dissolved, then add to the micelle solution.
[0047] Finally, 6 ml of 0.5 mol / L DMAB solution was added to the above solution to form an electrolyte solution.
[0048] (2) Electrodeposition.
[0049] Electrodeposition was performed in a typical three-electrode system, with a Pt wire as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and carbon paper as the working electrode. Repeated LSV scans were performed at a scan rate of 100 mV / s from -0.2 V to -2.0 V (vs Ag / AgCl), for six cycles, with a one-minute interval between each cycle, to avoid concentration gradients near the electrodes caused by continuous electrodeposition.
[0050] (3) Chemical deposition.
[0051] The electrodeposited carbon paper was kept stagnant in the electrolyte for a certain period of time, during which nitrogen protective gas was continuously circulated above the liquid surface. Finally, the carbon paper was removed and immersed in DMF to remove the diblock polymer, obtaining a mesoporous amorphous alloy film a-NiCoFeB loaded on the carbon paper.
[0052] (4) High-temperature calcination.
[0053] The mesoporous amorphous alloy film a-NiCoFeB obtained above was placed in a tube furnace, and a 4% H2 / Ar mixed gas was introduced. It was calcined at 350°C for 2 hours to obtain the mesoporous crystalline alloy film c-NiCoFeB-350. As a comparison, the mesoporous crystalline alloy films c-NiCoFeB-250 and c-NiCoFeB-450 were obtained by calcining at 250°C and 450°C for 2 hours.
[0054] like Figure 1 As shown, Figure 1 The red curve in the image is the X-ray diffraction curve of α-NiCoFeB. Figure 1 The green curve in the image is the X-ray diffraction curve of c-NiCoFeB-250. Figure 1 The blue curve in the image is the X-ray diffraction curve of c-NiCoFeB-350. Figure 1 The purple curve in the image represents the X-ray diffraction pattern of c-NiCoFeB-450. It can be seen that a-NiCoFeB does not exhibit any obvious diffraction peaks, only a weak, broad peak at 2θ = 45°. This characteristic matches the typical XRD pattern of amorphous materials, indicating that the prepared film has an amorphous structure.
[0055] like Figure 3 As shown, Figure 3 The red curve in the figure represents the oxygen evolution reaction activity curve of α-NiCoFeB. Figure 3 The blue curve in the image represents the oxygen evolution reaction activity curve of c-NiCoFeB. Figure 3 The gray curve in the figure represents the oxygen evolution reaction activity curve of RuO2. It can be seen that a-NiCoFeB exhibits superior catalytic efficiency, with an overpotential significantly lower than that of c-NiCoFeB and commercial RuO2.
[0056] like Figure 4 As shown, Figure 4 The red curve in the figure represents the potential curve of α-NiCoFeB. Figure 4 The gray curve in the figure represents the potential curve of RuO2. It can be seen that, compared to commercial RuO2, the potential of a-NiCoFeB remained almost stable during the 2000-hour test, indicating that this catalyst possesses good durability and stability in long-term reactions.
[0057] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.
Claims
1. A method for preparing a mesoporous amorphous alloy thin film, characterized in that, include: A mixed solution containing polymer micelles was obtained by mixing a diblock polymer, an organic solvent, water, and a metal salt precursor. A boron-containing reducing agent is added to the mixed solution to obtain an electrolyte; Using a Pt wire as the counter electrode, a saturated Ag / AgCl electrode as the reference electrode, and a conductive substrate as the working electrode, a three-electrode system was used to perform linear voltammetric scanning in the electrolyte to perform electrodeposition on the conductive substrate and obtain an initial deposition layer. The initial deposited layer is placed in the electrolyte and allowed to stand. Under the action of a protective gas, autocatalytic chemical deposition is carried out to continue growth on the initial deposited layer to obtain an initial alloy film. The initial alloy film is immersed in the organic solvent to remove the polymer micelles, thereby obtaining a mesoporous amorphous alloy film loaded on the conductive substrate.
2. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The diblock polymer is polystyrene-b-polyethylene oxide.
3. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The metal salt precursor includes nickel acetate, cobalt acetate, and ferric chloride.
4. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The boron-containing reducing agent is a dimethylaminoborane solution.
5. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The linear voltammetric scan has a potential window of -0.2 V to -2.0 V relative to the saturated Ag / AgCl electrode, a scan rate of 50 mV / s to 200 mV / s, and a scan cycle of 2 to 10 times.
6. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The protective gas includes nitrogen or argon.
7. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The organic solvent is N,N-dimethylformamide.
8. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The conductive substrate includes: carbon paper, carbon cloth, nickel foam, copper foil, or ITO conductive glass.
9. The method for preparing a mesoporous amorphous alloy thin film as described in claim 1, characterized in that, The method also includes placing the mesoporous amorphous alloy film in a tube furnace and calcining it under the action of a mixed gas including hydrogen and argon to obtain a mesoporous crystalline alloy film.