Method for enhancing activity of monatomic catalyst, fluorinated monatomic catalyst and water splitting hydrogen production method

Abstract

The invention relates to the technical field of contact electrocatalysis and energy materials, in particular to a method for enhancing the activity of a monatomic catalyst, a fluorinated monatomic catalyst and a water splitting hydrogen production method. The method for enhancing the activity of the monatomic catalyst comprises the following steps: providing a monatomic catalyst, and carrying out fluorination treatment on the surface of the monatomic catalyst by using a fluorine-containing silane organic solvent to obtain a fluorinated monatomic catalyst, according to the fluorinated monatomic catalyst, the contact electrification capability of the carrier is enhanced based on the contact electrocatalytic effect, and an interface electric field can be formed around the monatomic active center in the monatomic catalyst, so that the catalytic activity of the monatomic catalyst is enhanced. A brand new thought is provided for solving the technical problem that an existing monatomic catalyst is weak in catalytic activity, through the thought, the technical problem that the monatomic catalyst is weak in catalytic activity can be solved, and the monatomic catalyst capable of improving the catalytic activity can be applied to the field of hydrogen production to improve the hydrogen production efficiency.

Description

Technical Field

[0001] This invention relates to the field of contact electrocatalysis and energy materials technology, specifically to a method for enhancing the activity of single-atom catalysts, fluorinated single-atom catalysts, and a method for hydrogen production through water splitting. Background Technology

[0002] Single-atom catalysts (SACs), representing a major breakthrough in heterogeneous catalysis, have demonstrated immense potential in energy conversion and chemical synthesis due to their highest atom utilization efficiency and unique electronic structure. However, current research on SACs generally treats the support material as an inert substrate, thus limiting the improvement of catalytic performance. Furthermore, existing SAC-based catalytic systems often rely on external light fields, electric fields, or chemical sacrificial agents, which not only increases system complexity and operating costs but also limits their practical applications. In addition, the hydrogen production efficiency of existing SACs in pure water systems is often limited by slow water dissociation kinetics and insufficient proton supply. Traditional approaches typically promote water dissociation by alkalizing the electrolyte or using sacrificial agents, which not only increases the complexity of the entire system but may also introduce side reactions. Summary of the Invention

[0003] To address the technical problem of weak catalytic activity in existing single-atom catalysts, this invention provides a method for enhancing the activity of single-atom catalysts, a fluorinated single-atom catalyst, and a method for hydrogen production through water splitting.

[0004] This invention employs the following technical solution: a method for enhancing the activity of a single-atom catalyst, comprising providing a single-atom catalyst containing a support and a single atom supported on the support. A fluorinated single-atom catalyst is obtained by fluorinating the surface of the single-atom catalyst with a fluorinated organic solvent containing a fluorinated silane. The fluorinated single-atom catalyst enhances the contact electrification capability of the support based on the contact electrocatalytic effect, and the charge accumulation caused by contact electrification forms an interfacial electric field around the single-atom active center in the single-atom catalyst to enhance the reduction activity of the single-atom site, thereby enhancing the catalytic activity of the single-atom catalyst.

[0005] As a further improvement of the present invention, the organic solvent for the fluorinated silane is a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution.

[0006] As a further improvement of the present invention, the single-atom catalyst is Ru / SiO2.

[0007] As a further improvement of the present invention, the fluorination treatment time is 12h~48h.

[0008] As a further improvement of the present invention, the concentration of the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution is 1mM~20mM.

[0009] As a further improvement of the present invention, the carrier includes any one of organic polymers, inorganic oxides or carbon-based materials.

[0010] As a further improvement of the present invention, when the carrier is an organic polymer, it includes any one of polytetrafluoroethylene powder, nylon film, and cellulose microspheres.

[0011] As a further improvement of the present invention, when the carrier is an inorganic oxide, it includes any one of mesoporous silica, alumina, and titanium dioxide.

[0012] As a further improvement of the present invention, when the carrier is a carbon-based material, it includes any one of activated carbon, graphene, and nitrogen-doped carbon nanotubes.

[0013] As a further improvement of the present invention, the carrier may be in the form of powder, thin film material or three-dimensional porous structure.

[0014] As a further improvement of the present invention, when the carrier is in powder form, its particle size ranges from 100 nm to 10 μm.

[0015] As a further improvement of the present invention, when the carrier is in the form of a thin film material, its thickness is 10μm~200μm.

[0016] As a further improvement of the present invention, when the carrier has a three-dimensional porous structure, its pore size is 2nm~50nm.

[0017] The present invention also includes a fluorinated single-atom catalyst, which is obtained by the method for enhancing the activity of single-atom catalysts as described above. The fluorinated single-atom catalyst comprises a single-atom catalyst and an organic solvent containing a fluorinated silane; the mass-to-volume ratio of the single-atom catalyst to the organic solvent containing the fluorinated silane is 5 g: 1 L.

[0018] The present invention also includes a water splitting method for hydrogen production, comprising: providing a fluorinated single-atom catalyst as described above; adding the fluorinated single-atom catalyst and water in a mass-to-volume ratio of 0.1 g to 1.0 g: 1 L into a sealed reactor, and subjecting the reactor to ultrasonic treatment under an inert atmosphere, thereby causing alternating contact and separation between the fluorinated single-atom catalyst and water, resulting in the accumulation of electrons on the surface of the fluorinated single-atom catalyst; the accumulated electrons are transferred to hydrogen ions during subsequent contact and separation between the fluorinated single-atom catalyst and water, thereby reducing hydrogen ions to hydrogen gas.

[0019] As a further improvement of the present invention, the frequency of ultrasonic treatment is 20kHz~200kHz.

[0020] As a further improvement of the present invention, the water includes either pure water or seawater.

[0021] The technical solution provided by this invention has the following beneficial effects: (1) The key innovation of this scheme is to fully utilize the contact electrification characteristics of the support material in the single-atom catalyst based on the emerging technical path of contact electrocatalysis, thereby enhancing the contact electrification capability of the support. Furthermore, based on the charge accumulation phenomenon caused by contact electrification, a spontaneous high-intensity electric field can be constructed around the single-atom active center of the single-atom catalyst. The synergistic effect of these two factors significantly enhances the catalytic activity of the single-atom catalyst. This scheme utilizes the physical characteristic of contact electrocatalysis of the support to regulate the catalytic activity of the single-atom catalyst through the interfacial electric field it generates. This provides a novel approach to solving the technical problem of weak catalytic activity in existing single-atom catalysts. Moreover, this approach not only solves the technical problem of weak catalytic activity in single-atom catalysts but also allows the application of the enhanced catalytic activity single-atom catalyst in the field of hydrogen production to improve hydrogen production efficiency.

[0022] (2) The water splitting hydrogen production method provided in this scheme uses a fluorinated single-atom catalyst that has undergone fluorination treatment. On the one hand, it enhances the contact electrification ability of the support by utilizing the contact electrocatalytic property of the support, and promotes the dissociation of water molecules through frequent contact and separation with water, thereby providing a sufficient proton source for the subsequent hydrogen production reduction reaction. On the other hand, the charge accumulation phenomenon caused by the contact electrification effect on the support surface can also construct an interfacial electric field around the active sites of the single atoms. The interfacial electric field can not only enhance the reduction activity of the single-atom sites in the single-atom catalyst, but also generate a physical shielding effect, effectively improving the corrosion resistance and long-term stability of the single-atom catalyst. This allows the fluorinated single-atom catalyst to be applied to the complex hydrogen production environment of seawater electrolysis, thereby expanding its practical application prospects. Attached Figure Description

[0023] Figure 1 A flowchart of a method for enhancing the activity of single-atom catalysts provided by the present invention.

[0024] Figure 2 This is a schematic diagram of the mechanism for enhancing the catalytic activity of single-atom catalysts in the method for enhancing the activity of single-atom catalysts provided by the present invention.

[0025] Figure 3 This is a schematic diagram illustrating the mechanism of hydrogen production through hydrolysis based on Ru / F-SiO2 in this invention.

[0026] Figure 4 This is a graph showing the trend of hydrogen production concentration over time when different catalysts are used for hydrogen production in the performance testing section of this invention.

[0027] Figure 5 This is a graph showing the trend of hydrogen production over time during the stability test of the Ru / F-SiO2 single-atom catalyst in seawater in the performance testing section of this invention. Detailed Implementation

[0028] The present invention will now be further described in conjunction with specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0029] In the description of this invention, it should be noted that directional terms such as "center," "lateral," "longitudinal," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific scope of protection of this invention. The terms "first," "second," etc., in the specification and claims of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "comprising" and "having," and any variations thereof, in the specification and claims of this invention, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0030] To enhance the catalytic performance of single-atom catalysts, researchers have developed various strategies, primarily including precise control of the local coordination environment of single-atom sites, optimization of metal-support interactions, and induction of polarization using external field effects (such as light and electric fields). These methods, through chemical modification or external energy input, have improved the catalytic performance of single-atom catalysts to some extent. However, these strategies mainly focus on controlling the chemical properties of the catalyst itself, neglecting the significant impact of the physical properties of the support material on catalytic performance. It is particularly noteworthy that single-atom catalysts are typically supported on various dielectric support materials, and existing research often treats the support as an inert substrate, ignoring its potential physical functions, which limits further improvements in single-atom catalyst performance. The recently emerging contact electrocatalysis (CEC) technology offers a new solution for catalytic reactions through an innovative pathway of direct mechanical-chemical energy conversion. Studies have shown that under mechanical action, the support material can generate polarization with an intensity as high as 10⁻⁶ around it through the contact electrochemical effect. 9 An electric field of V / m. This high-intensity electric field generated during contact electrocatalysis can significantly improve the reactivity of metal catalysts. More importantly, due to the "point discharge" effect, the polarization effect of the interfacial electrostatic field on the active sites becomes more significant when the catalyst size is reduced to the atomic level. Based on this, this scheme proposes for the first time a method to enhance the activity of single-atom catalysts. Its key innovation lies in the ingenious use of the emerging technology of contact electrocatalysis, through reasonable material design, to construct a high-intensity electric field around the single-atom active center, thereby significantly improving catalytic performance. Please refer to... Figure 1 and Figure 2 A method for enhancing the activity of a single-atom catalyst includes providing a support and a single-atom catalyst supported on the support. The single-atom catalyst is fluorinated by fluorinating its surface with a fluorosilane-containing organic solvent to obtain a fluorinated single-atom catalyst. The fluorinated single-atom catalyst enhances the contact electrification ability of the support based on the contact electrocatalytic effect and forms an interfacial electric field around the single-atom active sites in the single-atom catalyst to enhance the reduction activity of the single-atom sites, thereby enhancing the catalytic activity of the single-atom catalyst. In this method, the enhanced catalytic activity of the single-atom catalyst mainly stems from two mechanisms: firstly, the surface of the support after fluorination promotes the dissociation of water molecules based on the contact electrification effect, providing a sufficient proton source for subsequent reduction reactions; secondly, the strong interfacial electric field formed after fluorination significantly improves the reduction activity of the single-atom sites in the single-atom catalyst. The synergistic effect of these two aspects enhances the catalytic activity of the single-atom catalyst.

[0031] The organic solvent for fluorosilanes can be a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution. The single-atom catalyst can be Ru / SiO2. Functional modification of the Ru / SiO2 single-atom catalyst surface with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FDTES) aims to enhance the catalyst's contact electrostatic ability. The mechanism by which 1H,1H,2H,2H-perfluorodecyltriethoxysilane can modify the single-atom catalyst is that, due to the strong electron affinity of the fluorine atom, the single-atom catalyst modified with 1H,1H,2H,2H-perfluorodecyltriethoxysilane more easily captures electrons from water upon contact, while hydrogen ions (H+) are absorbed. + The process of gaining electrons from the surface of a single-atom catalyst is relatively difficult to occur, leading to the accumulation of electrons on the surface of the single-atom catalyst. A schematic diagram of this mechanism is shown below. Figure 3 As shown in the figure, in this invention, the surface of the Ru / SiO2 catalyst is functionalized by 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FDTES). On the one hand, the fluorinated SiO2 substrate can promote water splitting through contact electrocatalysis (CEC)-driven water oxidation reaction, providing a proton source for the subsequent reduction hydrogen production process. On the other hand, the charge accumulation phenomenon caused by the contact electrochemical effect on the SiO2 support surface can also introduce a high-strength electric field at the interface. Ru atoms are polarized under this high-strength electric field, resulting in the accumulation of electrons on the surface of Ru atoms. The potential barrier for transferring electrons to hydrogen ions is reduced, thereby significantly improving the reduction hydrogen production activity of Ru single atoms.

[0032] The concentration of the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution is 1mM~20mM; the fluorination treatment time is 12h~48h. Since the fluorination reaction is a gradual permeation / film formation process, if the time is too short (e.g., less than 12h), the fluorinating agent may not be able to fully penetrate the material surface or matrix defects, resulting in a thin and discontinuous fluorinated film that cannot effectively improve the material's corrosion resistance, wear resistance, and surface conditioning effect. If the fluorination time is too long (more than 48h), it will damage the molecular chain structure of the material surface, leading to a decrease in surface catalysis and toughness. This scheme, by setting the fluorination time to 12h~48h, allows the fluorinating agent to undergo sufficient chemical adsorption or chemical reaction with the material surface, forming a uniform and dense surface fluorinated modification layer, thereby ensuring the stable performance of the treated single-atom catalyst.

[0033] It is understandable that when fluorinating single-atom catalysts, they can also be modified by small molecules such as fluorinated silane coupling agents and perfluoropolyethers, or by plasma treatment with fluorine-containing gases such as CF4 / SF6 to achieve fluorination of the single-atom catalyst surface.

[0034] The support can be any one of organic polymers, inorganic oxides, or carbon-based materials. All three types of supports can be modified by surface modification to regulate the electronic structure of metal single atoms, optimizing the activity of single-atom catalysts and thus improving their catalytic activity. Specifically, when the support is an organic polymer, it can include any one of polytetrafluoroethylene (PTFE) powder, nylon film, ethyl cellulose microspheres, etc. When the support is an inorganic oxide, it can include any one of mesoporous silica, alumina, titanium dioxide, etc. For oxides, their surfaces can contain a large number of active sites such as hydroxyl groups (-OH), oxygen vacancies, and lattice defects. These sites can firmly anchor isolated metal atoms through coordination bonds or charge transfer effects, forming stable active centers and preventing single atoms from migrating and agglomerating into nanoparticles during the reaction, thereby significantly improving the structural stability of the single-atom catalyst. When the support is a carbon-based material, it can include any one of activated carbon, graphene, nitrogen-doped carbon nanotubes, etc. For carbon-based materials (such as activated carbon and graphene), they have excellent electronic conductivity, which can accelerate the electron transfer between the single-atom active center and the external circuit, thereby significantly improving the catalytic kinetic rate of the single-atom catalyst.

[0035] The support can take the form of powder, thin film, or three-dimensional porous structure. When the support is in powder form, its particle size can range from 100 nm to 10 μm. For powder, the particle size is typically in the nanometer to micrometer range, lacking a continuous dense structure; the particles are loosely packed, providing an extremely high specific surface area. This allows the single-atom sites loaded on the support to be fully exposed, reducing the probability of single-atom sites being encapsulated and significantly improving atomic utilization. When the support is in thin film form, its thickness can range from 10 μm to 200 μm. Thin film materials are typically prepared using methods such as vapor deposition, spin coating, and blade coating. Single-atom sites are generally anchored to the film surface or outer layer and are not easily detached or lost, improving the stability of the single-atom catalyst. When the support is in three-dimensional porous structure, its pore size can range from 2 nm to 50 nm. For three-dimensional porous structures, the porous structure can provide high-density single-atom anchoring points, while the pores can also serve as transport channels for reactants and products, significantly reducing mass transfer resistance, preventing reactants from accumulating on the surface of active sites, and improving the catalytic efficiency and lifetime of single-atom catalysts.

[0036] This embodiment also provides a fluorinated single-atom catalyst, which can be obtained by the method of enhancing the activity of the single-atom catalyst as described above. The fluorinated single-atom catalyst includes a single-atom catalyst and an organic solvent containing fluorinated silane; the mass-volume ratio of the single-atom catalyst to the organic solvent containing fluorinated silane is 5g:1L. The single-atom catalyst can be Ru / SiO2. The organic solvent containing fluorinated silane can be 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution. The specific process of fluorinating Ru / SiO2 with 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution is described below: (1) Take 1g of commercial silica-supported ruthenium single-atom catalyst Ru / SiO2, the ruthenium loading in the single-atom catalyst Ru / SiO2 is 0.5wt%. First, rinse the single-atom catalyst Ru / SiO2 three times each with anhydrous ethanol and ultrapure water to remove surface impurities. Then place the rinsed single-atom catalyst in a vacuum drying oven at 40℃ and dry for 24 hours. (2) Prepare 200 mL of a 5 mM 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution. Add the pretreated Ru / SiO2 single-atom catalyst from step (1) to the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution and stir at 600 rpm for 24 hours at room temperature to complete the fluorination modification of the Ru / SiO2 single-atom catalyst surface. After the reaction, rinse three times with isopropanol and finally dry overnight under vacuum at 40°C to obtain the fluorinated single-atom catalyst Ru / F-SiO2. This scheme can enhance the contact charging ability of the single-atom catalyst through the above fluorination treatment, achieve a breakthrough improvement in the performance of the single-atom catalyst, and thus lay the foundation for subsequent water cracking and hydrogen production by the fluorinated single-atom catalyst. Furthermore, based on the aforementioned advantages of the fluorinated single-atom catalyst provided by this scheme, the fluorinated single-atom catalyst provided by this scheme can not only be applied to the field of hydrogen production, but also extended to important chemical processes such as carbon dioxide reduction and efficient ammonia synthesis, thereby significantly broadening the application field of fluorinated single-atom catalysts.

[0037] Based on the fluorinated single-atom catalyst described above, a novel water splitting method for hydrogen production can be constructed. This method includes: providing a fluorinated single-atom catalyst as described above, and adding the fluorinated single-atom catalyst and water in a mass-to-volume ratio of 0.1 g to 1.0 g: 1 L to a sealed reactor. Under an inert atmosphere, ultrasonic treatment is performed, allowing alternating contact and separation between the fluorinated single-atom catalyst and water, resulting in the accumulation of electrons on the surface of the fluorinated single-atom catalyst. These accumulated electrons are transferred to hydrogen ions during subsequent contact and separation between the fluorinated single-atom catalyst and water, thereby reducing the hydrogen ions to hydrogen gas. The principle behind the water splitting method for hydrogen production provided by this scheme effectively increasing the hydrogen production rate is as follows: firstly, this scheme enhances the contact electrocatalysis capability of the support by utilizing its contact electrocatalytic properties, and secondly, promotes the dissociation of water molecules through frequent contact and separation with water, thus providing a sufficient proton source for the subsequent reduction reaction for hydrogen production. On the other hand, the charge accumulation phenomenon caused by contact electrocoagulation on the support surface can also construct an interfacial electric field around the active sites of single atoms. This interfacial electric field not only enhances the reduction activity of single-atom sites in the single-atom catalyst but also generates a physical shielding effect, effectively improving the corrosion resistance and long-term stability of the single-atom catalyst. This allows fluorinated single-atom catalysts to be applied in the complex hydrogen production environment of seawater electrolysis, thus expanding their practical application prospects. Furthermore, this scheme utilizes the physical property of contact electrocatalysis on the support to regulate the catalytic activity of the single-atom catalyst through the interfacial electric field it generates. This provides a novel approach to solving the technical problem of weak catalytic activity in existing single-atom catalysts. Moreover, this approach not only solves the problem of weak catalytic activity in single-atom catalysts but also allows for the application of single-atom catalysts with enhanced catalytic activity in hydrogen production to improve hydrogen production efficiency.

[0038] The ultrasonic treatment frequency in the water splitting hydrogen production method provided in this scheme can be 20kHz~200kHz, and the water splitting hydrogen production method can be carried out at room temperature. The fluorinated single-atom catalyst can be Ru / F-SiO2. The mechanism based on Ru / F-SiO2 and according to the above-described water splitting hydrogen production method is shown in the schematic diagram below. Figure 3 As shown. (Through) Figure 3 It is known that during the alternating contact and separation process with water, fluorinated single-atom catalysts can accumulate a large number of electrons on their surface based on contact electrocatalysis. These accumulated electrons can be transferred to hydrogen ions during the subsequent contact and separation process between the fluorinated single-atom catalyst and water, thereby achieving the purpose of hydrogen production.

[0039] In summary, the hydrogen production method constructed based on the theory of enhancing the catalytic activity of single-atom catalysts through electrostatic polarization has the following advantages: (1) In terms of catalytic performance, the hydrogen production rate of the water splitting hydrogen production method provided by this scheme is about 7.04 times higher than that of existing hydrogen production methods; (2) In terms of energy consumption and cost, this scheme only requires mechanical energy input, which simplifies the preparation process, reduces the cost of catalysts in the hydrogen production process, significantly improves the practicality and economy of hydrogen production technology, and solves the technical problem that traditional hydrogen production methods require external energy input (such as light fields, electric fields or chemical sacrificial agents), resulting in high operating costs of the entire hydrogen production system. In terms of operational convenience, the hydrogen production method of this scheme is free from dependence on sacrificial agents and complex equipment, and realizes simple operation at room temperature and pressure. In terms of environmental adaptability, this scheme fluorinates the single-atom catalyst, enabling the single-atom catalyst to exhibit excellent stability and continuous catalytic activity in a real water environment.

[0040] Performance testing To verify the hydrogen production performance of the water splitting hydrogen production method provided in this embodiment, the technicians conducted the following experiments.

[0041] Hydrogen production experiment: Three groups of experiments were set up, namely the experimental group, the control group, and the blank control group.

[0042] For the experimental group, the specific steps are as follows: Disperse 10-20 mg of Ru / F-SiO2 in 50 mL of deionized water (resistivity 18.2 MΩ·cm), and place the deionized water containing Ru / F-SiO2 into a 150 mL borosilicate glass reactor. First, bubble high-purity (99.999%) argon gas into the borosilicate glass reactor for 15-30 minutes to remove dissolved oxygen and air. Then, close the inlet and outlet valves of the sealed borosilicate glass reactor and place it in a 40 kHz ultrasonic cleaning tank, maintaining the water temperature at 25 ± 2 °C.

[0043] For the control group, the operating procedures were exactly the same as those for the experimental group, except that the catalyst used was Ru / SiO2 that had not undergone fluorination treatment.

[0044] For the blank control group, the operating procedure is exactly the same as that of the experimental group, except that no catalyst is added to the water.

[0045] For the three hydrogen production experiments described above, 1 mL of top gas was extracted through the sampling port at 0, 30, 60, 120, and 180 minutes, respectively. Quantitative analysis of hydrogen was performed using a gas chromatograph-TCD equipped with a thermal conductivity detector (GC-TCD). Figure 4 Through the analysis of Figure 4Analysis revealed that the blank control group produced virtually no hydrogen through the aforementioned water splitting method. However, for both the control and experimental groups, the hydrogen production rate in the control group, using the single-atom catalyst Ru / SiO2, was approximately 0.223 mmol·g⁻¹ within 180 min. -1 ·h -1 The experimental group, using fluorinated Ru / F-SiO2 as a single-atom catalyst, achieved a hydrogen production rate of approximately 1.57 mmol·g over 180 min. -1 ·h -1 Therefore, it can be seen that fluorination of the single-atom catalyst Ru / SiO2 can significantly improve the hydrogen production rate, by approximately 7.04 times. This confirms the strong synergistic effect of the electrostatic polarization strategy. Through chemical means such as fluorination modification, the intensity of contact electrification and the interfacial electric field can be controlled, achieving controllable enhancement of catalytic performance.

[0046] Stability test The specific steps are as follows: Disperse 10-20 mg of Ru / F-SiO2 in 50 mL of seawater, and place the deionized water containing Ru / F-SiO2 into a 150 mL borosilicate glass reactor. First, bubble high-purity (99.999%) argon gas into the borosilicate glass reactor for 15-30 minutes to remove dissolved oxygen and air. Then, close the inlet and outlet valves of the sealed borosilicate glass reactor and place it in a 40 kHz ultrasonic cleaning tank, maintaining the water temperature at 25 ± 2 °C.

[0047] 1 mL of top gas was extracted through the sampling port at 0, 20, 40, 60, 80, 100, 120, 140, 160, 180, and 200 hours, and hydrogen was quantitatively analyzed using a gas chromatograph equipped with a thermal conductivity detector (GC-TCD). Figure 5 Through the analysis of Figure 5 Analysis shows that the hydrogen production efficiency of the water splitting method provided in this scheme is consistently above 1.06 mmol·g⁻¹ within 200 h. -1 ·h -1The fluorinated single-atom catalyst exhibits high activity even after 200 hours of continuous operation, maintaining over 90% of its initial activity. This demonstrates that the fluorinated single-atom catalyst provided by this invention maintains high activity even after 200 hours of continuous operation in real seawater, showcasing its excellent resistance to complex ion interference and long-term stability, thus greatly expanding its application scenarios in the hydrogen evolution field. Therefore, the electrostatic polarization strategy proposed in this invention utilizes a spontaneously formed interfacial electric field to regulate the catalytic behavior of the single-atom catalyst, providing a universal and efficient method for designing high-performance, high-stability single-atom catalysts. Furthermore, the fluorinated single-atom catalyst, after fluorination treatment, demonstrates excellent hydrogen production efficiency in both deionized water and seawater, which is of great significance for promoting the development of green energy technologies and provides a new technical path for the development of marine hydrogen energy.

[0048] The basic principles, main features, and advantages of this invention have been described above. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made without departing from the spirit and scope of the invention, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection claimed by this invention is defined by the appended claims and their equivalents.

Claims

1. A method for enhancing the activity of a single-atom catalyst, characterized in that, It includes: A single-atom catalyst comprising a support and a single atom supported on the support is provided; Fluorinated single-atom catalysts are obtained by fluorinating the surface of single-atom catalysts with organic solvents containing fluorinated silanes. Fluorinated single-atom catalysts enhance the contact electrification ability of the support based on the contact electrocatalytic effect, and the charge accumulation caused by contact electrification can form an interfacial electric field around the single-atom active center in the single-atom catalyst to enhance the reduction activity of the single-atom site, thereby enhancing the catalytic activity of the single-atom catalyst.

2. The method for enhancing the activity of a single-atom catalyst as described in claim 1, characterized in that, The organic solvent for the fluorinated silane is a 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution. And / or, the single-atom catalyst is Ru / SiO2; And / or, the fluorination treatment time is 12h~48h.

3. The method for enhancing the activity of a single-atom catalyst as described in claim 2, characterized in that, The concentration of the 1H,1H,2H,2H-perfluorodecyltriethoxysilane / isooctane solution is 1 mM to 20 mM.

4. The method for enhancing the activity of a single-atom catalyst as described in claim 1, characterized in that, The carrier includes any one of organic polymers, inorganic oxides, or carbon-based materials.

5. The method for enhancing the activity of a single-atom catalyst as described in claim 4, characterized in that, When the carrier is an organic polymer, it includes any one of polytetrafluoroethylene powder, nylon film, and cellulose microspheres; And / or, when the carrier is an inorganic oxide, it includes any one of mesoporous silica, alumina, and titanium dioxide; And / or, when the carrier is a carbon-based material, it includes any one of activated carbon, graphene, and nitrogen-doped carbon nanotubes.

6. The method for enhancing the activity of a single-atom catalyst as described in claim 1, characterized in that, The carrier can be in the form of powder, thin film material, or three-dimensional porous structure.

7. The method for enhancing the activity of a single-atom catalyst as described in claim 6, characterized in that, When the carrier is in powder form, its particle size ranges from 100 nm to 10 μm. And / or, when the carrier is a thin film material, its thickness is 10μm~200μm; And / or, when the carrier has a three-dimensional porous structure, its pore size is 2nm~50nm.

8. A fluorinated single-atom catalyst, characterized in that, It is obtained by the method of enhancing the activity of a single-atom catalyst as described in any one of claims 1-7, wherein the fluorinated single-atom catalyst comprises a single-atom catalyst and an organic solvent containing a fluorinated silane; the mass-to-volume ratio of the single-atom catalyst to the organic solvent containing the fluorinated silane is 5 g: 1 L.

9. A method for hydrogen production through water splitting, characterized in that, It includes: Provide a fluorinated single-atom catalyst as described in claim 8; The fluorinated single-atom catalyst and water are added to a sealed reactor at a mass-volume ratio of 0.1g to 1.0g: 1L, and ultrasonic treatment is performed under an inert atmosphere. This allows the fluorinated single-atom catalyst and water to alternately contact and separate, accumulating electrons on the surface of the fluorinated single-atom catalyst. The accumulated electrons are transferred to hydrogen ions during the subsequent contact and separation process between the fluorinated single-atom catalyst and water, thereby reducing hydrogen ions to hydrogen gas.

10. The water splitting method for hydrogen production as described in claim 9, characterized in that, The frequency of the ultrasonic treatment is 20kHz~200kHz; And / or, the water includes either pure water or seawater.

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