Controllable preparation method of catalyst with highly dispersed active components

Abstract

The invention relates to a controllable preparation method of a catalyst with highly dispersed active components, which realizes epitaxial growth and high dispersion of the active components on the surface of a carrier through lattice matching, and specifically comprises the step of realizing epitaxial growth and high dispersion of the active components on the surface of the carrier through a lattice matching principle. The preparation method comprises the following specific steps: selecting a specific carrier with an adjustable lattice constant, and preparing and calcining; measuring lattice parameters of the carrier as a basis for screening active components; selecting lattice-matched active components based on the parameter; and promoting the active components to form a uniform epitaxial growth layer on the surface of the carrier by using a lattice matching effect through a dipping, hydrothermal or vapor deposition method, and carrying out post-treatment to obtain a finished product of the catalyst. Compared with the prior art, through lattice matching, epitaxial growth and high dispersion of active components on the surface of the carrier are achieved, the activity and stability of the catalyst are effectively improved, and the catalyst is suitable for various oxidation-reduction reactions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material preparation, and particularly relates to a controllable preparation method of a catalyst with highly dispersed active components. BACKGROUND

[0002] The noble metal catalysts exhibit excellent catalytic performance in redox reactions, and are widely used in fuel cells, hydrogen production by water electrolysis, tail gas treatment and other fields. However, the high cost and limited resource reserves of noble metal catalysts limit their large-scale application, so improving the utilization efficiency and catalytic performance of noble metal catalysts has become a research hotspot. Traditional catalyst preparation methods such as impregnation method, coprecipitation method and sol-gel method are difficult to realize the high dispersion of active components, and often lead to the agglomeration of active components on the surface of the carrier, thereby affecting the activity and stability of the catalyst.

[0003] In view of the above problems, there are various attempts in the prior art. For example, the publication CN102470362A proposes a waste gas purification catalyst and a manufacturing method thereof, which grows noble metal particles epitaxially relative to the crystalline metal oxide carrier, and uses a masking agent to mask the surface of the carrier to inhibit the sintering and growth of the noble metal particles. Although this method improves the dispersion of noble metal to some extent, it still has limitations in practical application: the selection and processing conditions of the masking agent may not completely cover the defect area on the surface of the carrier, leading to the preferential adsorption of noble metal particles on the crystalline edge or step area, rather than uniform dispersion on the platform area, thereby causing the risk of local agglomeration. In addition, this method is insufficient in controlling the loading of noble metal on the internal surface of the carrier (such as the inner wall of the fine pores), and it is difficult to realize the overall high dispersion of active components.

[0004] Similarly, the publication CN116440900A provides a three-way catalyst and a preparation method thereof, which forms a solid solution by modifying CeO2-ZrO2 composite oxide with a doping element, and constructs a heterojunction to enhance the thermal stability and catalytic efficiency. Although this technology improves the oxygen vacancy density through in-situ nucleation of heterogeneous phase and doping-induced lattice distortion, it is still insufficient in controlling the high dispersion of active components: noble metal particles are prone to migration and agglomeration during high-temperature treatment due to the uneven interface energy barrier of the carrier, especially when the proportion of the doping element or the ratio of the electronic auxiliary agent is improper, the noble metal cannot be effectively anchored, leading to a decrease in catalytic active sites and performance degradation.

[0005] Therefore, the key problem commonly existing in the prior art is the difficulty in realizing the high dispersion of active components, which often leads to the agglomeration of active components on the surface of the carrier, thereby affecting the activity and stability of the catalyst. This technical problem directly restricts the improvement of the efficiency and the prolongation of the life of the noble metal catalyst. SUMMARY

[0006] The present application aims to overcome the defects of the prior art and provide a controllable catalyst preparation method with highly dispersed active components, lattice matching, and epitaxial growth and highly dispersed active components on the surface of the carrier.

[0007] The object of the present application can be achieved by the following technical solutions: The present application provides a controllable catalyst preparation method with highly dispersed active components, lattice matching, and epitaxial growth and highly dispersed active components on the surface of the carrier, which specifically comprises: S1, selecting a metal oxide or solid solution thereof with adjustable lattice constant and stable structure as the carrier, the metal oxide being selected from Sn 0.2 Ti 0.8 O2, In x Ti 1-x O2, CeO2-ZrO2, x being 0.01-0.99, the carrier being prepared by one of a hydrothermal method, a sol-gel method, and a co-precipitation method and being calcined and shaped; S2, determining the lattice parameters of the carrier after calcination and shaping by XRD or HRTEM as reference information for the selection of active components; S3, selecting active components based on the reference information, the active components including at least one of noble metal nanoparticles, noble metal single atoms, and bimetallic alloys; S4, impregnating, hydrothermal, or vapor deposition of the active components and the carrier, and using the effect of lattice matching to promote the active components to form a uniform epitaxial growth layer on the surface of the carrier, thereby realizing the highly dispersed active components, and obtaining a catalyst product through post-processing; The active components can form metal active sites with the carrier by lattice matching.

[0008] Further, in S3, the specific process of selecting active components based on the reference information comprises: Analyzing the lattice parameters of the preselected active components to obtain the crystal structure and size information of the active components; Comparing the lattice parameters of the active components with the lattice parameters of the carrier after calcination and shaping, and selecting active components with lattice parameters matching the carrier after calcination and shaping, so that the active components can effectively epitaxially grow and highly disperse on the surface of the carrier.

[0009] Further, the specific process of selecting active components with lattice parameters matching the carrier after calcination and shaping comprises: Obtaining the lattice parameter data of the preselected active components; Using material science software analysis and XRD characterization technology to compare the crystal structure and lattice parameters of the active components and the carrier after calcination and shaping; The lattice mismatch rate is calculated by comparing the lattice parameters of the active component and the support after calcination and molding, i.e., Δa / a, wherein Δa is the difference between the lattice parameters of the active component and the support, and a is the lattice parameter of the support; The epitaxial growth process of the active component on the surface of the support is simulated using simulation software to predict the dispersion and interaction thereof; The interaction energy between the active component and the support is calculated by density functional theory software to predict the possibility and stability of epitaxial growth; Based on the analysis simulation and calculation results, the matching degree of different active components and supports is evaluated, and the best active component is selected.

[0010] Further, in the process of obtaining the lattice parameter data of the preselected active component, the lattice parameter data of the active component is obtained from the Crystallography Open Database of the International Union of Crystallography or scientific literature; The material science software includes one of Materials Studio, CrystalMaker, and VESTA; The epitaxial growth process of the active component on the surface of the support is simulated using VASP or Quantum ESPRESSO simulation software.

[0011] Further, the matching degree of different active components and supports satisfies the following conditions: Complete lattice matching: the lattice constant of the support and the active component is close, and no lattice distortion occurs at the interface; Partial lattice matching: the lattice constants of the two materials are not completely the same, but the mismatch rate is less than 6%.

[0012] Further, the specific process of simulating the epitaxial growth process of the active component on the surface of the support using simulation software to predict the dispersion and interaction thereof includes: An atomic structure model of the support surface and a crystal structure model of the active component are constructed, and then the required parameter conditions for simulation are set. The adsorption, migration, and final nucleation assembly of the active component atoms or molecules on the surface of the support are simulated by molecular dynamics method or Monte Carlo method. The uniformity of the dispersion of the active component on the surface of the support and the strength of the interaction therebetween are evaluated by analyzing the position distribution, coordination environment, and evolution of system energy of the active component atoms in the simulation results. The specific process of calculating the interaction energy between the active component and the support by density functional theory software to predict the possibility and stability of epitaxial growth includes: A periodic supercell calculation model is constructed for the interface between the active component and the carrier, the geometric structure of the model is optimized until the total energy of the system converges to a set threshold, and then the total energy of the interface system, the energy of the isolated carrier and the energy of the isolated active component are calculated, wherein the relationship between the three is that the interaction energy of the interface is equal to the total energy of the system minus the energy of the carrier and then minus the energy of the active component, and the negative value of the interaction energy indicates that the combination is stable, and the greater the absolute value, the easier the epitaxial growth and the more stable the structure; Further, based on the analysis simulation and calculation results, the matching degree of different active components and carriers is evaluated, and the specific process of selecting the best active component includes: The lattice mismatch rate values between each candidate active component and the carrier are compared, the components with a mismatch rate lower than 6% are listed as primary selected objects, then the dispersion indexes predicted by the molecular simulation are comprehensively considered, including the surface coverage and particle size distribution of the active component, and the interaction energy size calculated by the density functional theory, based on the set selection standard, the active component with a more negative interaction energy value, i.e. a stronger combination, and a uniform dispersion structure formed by simulation is preferentially selected, so as to determine the active component with the best lattice matching degree with the carrier as the final selection.

[0013] Further, in S4, the active component and the carrier are combined by one of impregnation, hydrothermal and vapor deposition, and the lattice matching effect is used to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, and the specific process includes: The precursor solution of the active component is mixed with the carrier powder, and the temperature and reaction time are controlled during the impregnation or hydrothermal or vapor deposition process to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, and the lattice matching effect enables the active component to be uniformly distributed on the surface of the carrier to form a highly dispersed structure, so as to obtain a catalyst precursor structure.

[0014] Further, the process of controlling the temperature and reaction time during impregnation or hydrothermal or vapor deposition includes: Temperature control: the temperature of the active component precursor solution is controlled in the range of 40-150℃ by water bath to ensure uniform dispersion of the active component; Reaction time: the reaction time of impregnation, hydrothermal, vapor deposition and other methods is controlled in the range of 5-25 hours to enable the active component to fully contact and mix with the carrier, while avoiding excessive reaction to cause agglomeration of the active component.

[0015] Further, the process of post-treatment includes any one or more of drying, filter washing, drying, reduction, calcination, tabletting, grinding and sieving.

[0016] As an embodiment of the present application, the specific process includes the following steps: Specifically, the active component is mixed with the carrier, the effect of lattice matching is utilized to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, thereby realizing high dispersion of the active component, and finally through post-processing, a catalyst product is obtained, and the preparation steps include, in addition to lattice matching: Mixing: the uniformly ground carrier powder is weighed and added to the previously prepared suspension containing RuO2 nanoparticles; Water bath stirring: the mixture is stirred for 16 hours under the condition of a water bath at 50°C to ensure uniform mixing and preliminary interaction between the active component and the carrier; Concentration: the stirred mixed solution is transferred to a round-bottom flask, and rotary evaporation is performed under reduced pressure to obtain a catalyst precursor loaded with RuO2 nanoparticles; Drying: the precursor is dried at 150°C in an air atmosphere for 16 hours to obtain a solid powder; Washing: the solid powder is washed with deionized water and anhydrous ethanol for multiple times until there is no residual chloride ion in the filtrate; Calcination: the washed sample is calcined at 450°C in an air atmosphere for 16 hours to obtain the final catalyst powder; Shaping: the calcined catalyst powder is tableted, ground, and sieved to obtain particles of 40-60 mesh.

[0017] As another embodiment of the present application, the following steps are specifically included: the active component is mixed with the carrier, the effect of lattice matching is utilized to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, thereby realizing high dispersion of the active component, and finally through post-processing, a catalyst product is obtained, and the preparation steps include, in addition to lattice matching: Preparation of rutile TiO2 as a carrier; The precursor of Pt is introduced onto the TiO2 carrier by impregnation or chemical vapor deposition method, the Pt precursor is decomposed and forms a PtO2 atomic layer on the surface of TiO2; After the PtO2 atomic layer is formed, reduction treatment is performed to form a close interface between PtO2 and TiO2, and a Pt / PtO2 / TiO2 structure is formed.

[0018] Compared with the prior art, the present application has the following technical advantages: 1) This invention focuses on the lattice matching between the support and the active component. By optimizing the matching between the metal oxide support and the noble metal oxide with a special crystal form, it achieves epitaxial growth and high dispersion of the active component on the support surface. Lattice matching effectively avoids the aggregation of the active component, significantly improving the activity and stability of the catalyst. The catalyst prepared by this method is suitable for various redox reaction systems, and the preparation method has a certain degree of universality. It not only improves the performance of the catalyst but also expands its application potential in environmental remediation and energy conversion.

[0019] 2) The catalyst preparation method provided by this invention achieves uniform epitaxial growth and high dispersion of active components on the support surface through precise lattice matching technology, significantly improving catalyst performance. This not only enhances the utilization rate of active components and the stability of the catalyst but also broadens its application range in various redox reactions. Through carefully designed lattice matching conditions, the catalyst exhibits excellent catalytic activity, providing strong support for the development of clean energy technologies and environmental catalysis technologies.

[0020] 3) The method of this invention, through scientific data analysis and the application of simulation software, achieves precise evaluation and selection of the matching degree between the active component and the support, thereby optimizing the design and preparation process of the catalyst. The universality and high efficiency of this method provide new ideas for the innovative development of catalysts, contributing to technological progress and industrial applications in related fields, particularly in improving the utilization efficiency of precious metal catalysts and reducing costs, which has significant practical implications. Attached Figure Description

[0021] Figure 1 The images shown are XRD patterns of RuO2 active components before and after loading onto different carriers in Example 1. The small image in the upper right corner shows the magnified signals at 28.1° and 35.1°. Figure 2 For example, (A) RuO2 / Aanatase-TiO2 and (B) RuO2 / Sn in Example 1 0.2 Ti 0.8 EDS-Mapping characterization results of O2 samples.

[0022] Figure 3 The Pt-Ru / Sn prepared in Example 2 0.2 Ti 0.8 EDS-Mapping characterization results of O2 bimetallic catalysts.

[0023] Figure 4 The Pt@Ru / Sn prepared in Example 3 0.2 Ti 0.8 EDS-Mapping characterization results of O2 catalyst.

[0024] Figure 5 Flow chart of controllable preparation method of active component highly dispersed catalyst in the application. DETAILED DESCRIPTION

[0025] The application will be described in detail below with reference to the drawings and specific examples. In the technical solution, if the preparation methods, materials, structures or component ratios and other features that are not explicitly described are considered as common technical features disclosed in the prior art.

[0026] Example 1 The controllable preparation method of active component highly dispersed catalyst in the embodiment realizes epitaxial growth and high dispersion of the active component on the surface of the carrier through lattice matching, and specifically includes the following steps: S1, a metal oxide or a solid solution thereof with adjustable lattice constant and stable structure is selected as the carrier, and the metal oxide is selected from Sn 0.2 Ti 0.8 O2, In x Ti 1-x O2, CeO2-ZrO2, x is 0.01-0.99, and the carrier is prepared by one of a hydrothermal method, a sol-gel method and a coprecipitation method and is calcined and shaped; S2, the lattice parameters of the carrier after calcination and shaping are determined by XRD or HRTEM as reference information for selection of the active component; S3, the active component is selected based on the reference information, and the active component includes at least one of a noble metal nanoparticle, a noble metal single atom and a bimetallic alloy; S4, the active component and the carrier are combined by one of impregnation, hydrothermal treatment and vapor deposition, and the effect of lattice matching is used to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, so that high dispersion of the active component is realized, and a catalyst finished product is obtained through post-processing; The active component can form a metal active site with the carrier by lattice matching.

[0027] In S3, the specific process of selecting the active component based on the reference information includes: The lattice parameters of the preselected active component are analyzed to obtain crystal structure and size information of the active component; The lattice parameters of the active component are compared with the lattice parameters of the carrier after calcination and shaping, and the active component with lattice parameters matching the carrier after calcination and shaping is selected, so that the active component can realize effective epitaxial growth and high dispersion on the surface of the carrier.

[0028] In specific implementation, the specific process of selecting the active component with lattice parameters matching the carrier after calcination and shaping includes: obtaining lattice parameter data of pre-selected active components; comparing the crystal structure and lattice parameters of the active component and the support after calcination and shaping using material science software analysis and XRD characterization techniques; comparing the lattice parameters of the active component and the support after calcination and shaping, calculating the lattice mismatch rate, i.e. Δa / a, where Δa is the difference in lattice parameters between the active component and the support, and a is the lattice parameter of the support; simulating the epitaxial growth process of the active component on the surface of the support using simulation software to predict its dispersion and interaction; calculating the interaction energy between the active component and the support using density functional theory software to predict the possibility and stability of epitaxial growth; based on the results of analysis, simulation and calculation, evaluating the matching degree of different active components and supports, and selecting the best active component.

[0029] In specific implementation, in the process of obtaining lattice parameter data of pre-selected active components, the lattice parameter data of the active component is obtained from the Crystallography Open Database of the International Union of Crystallography or scientific and technological literature; The material science software includes one of Materials Studio, CrystalMaker, and VESTA; The simulation software VASP or Quantum ESPRESSO is used to simulate the epitaxial growth process of the active component on the surface of the support.

[0030] In specific implementation, the matching degree of different active components and supports meets the following conditions: complete lattice matching: the lattice constant of the support is close to that of the active component, and no lattice distortion occurs at the interface; partial lattice matching: the lattice constants of the two materials are not completely the same, but the mismatch rate is less than 6%.

[0031] In specific implementation, the specific process of simulating the epitaxial growth process of the active component on the surface of the support using simulation software to predict its dispersion and interaction includes: constructing an atomic structure model of the support surface and a crystal structure model of the active component, then setting the required parameter conditions for simulation, using molecular dynamics method or Monte Carlo method to simulate the whole process of adsorption, migration and finally nucleation and assembly of active component atoms or molecules on the surface of the support, and evaluating the uniformity of the dispersion of the active component on the surface of the support and the strength of the interaction between the two by analyzing the position distribution, coordination environment and evolution of system energy of the active component atoms in the simulation results; In specific implementation, the specific process of calculating the interaction energy between the active component and the support using density functional theory software to predict the possibility and stability of epitaxial growth includes: A periodic supercell calculation model of the interface between the active component and the carrier is constructed, the geometric structure of the model is optimized until the total energy of the system converges to a set threshold, and then the total energy of the interface system, the energy of the isolated carrier and the energy of the isolated active component are calculated, respectively, wherein the relationship among the three is that the interaction energy is equal to the total energy of the system minus the carrier energy minus the active component energy, and the negative value of the interaction energy indicates that the combination is stable, and the greater the absolute value, the easier the epitaxial growth and the more stable the structure. In specific implementation, based on the analysis simulation and calculation results, the matching degree of different active components and carriers is evaluated, and the specific process of selecting the best active component includes: The lattice mismatch rate values between each candidate active component and the carrier are compared, and the components with a mismatch rate lower than 6% are listed as primary selection objects, then the dispersion indexes predicted by molecular simulation are comprehensively considered, including the surface coverage and particle size distribution of the active component, and the interaction energy size calculated by density functional theory, based on the set selection standard, the active component with a more negative interaction energy value, i.e. stronger combination, and which can form a uniform dispersion structure as shown in simulation is preferentially selected, so as to determine the active component with the best lattice matching degree with the carrier as the final selection.

[0032] In specific implementation in S4, the specific process of using one of impregnation, hydrothermal and vapor deposition to form a uniform epitaxial growth layer of the active component on the surface of the carrier by the effect of lattice matching includes: The precursor solution of the active component is mixed with the carrier powder, and the temperature and reaction time are controlled during impregnation or hydrothermal or vapor deposition to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, and the effect of lattice matching enables the active component to be uniformly distributed on the surface of the carrier to form a highly dispersed structure, thereby obtaining a catalyst precursor structure.

[0033] The embodiment overcomes the key technical problems in the prior art, i.e. the agglomeration of the active component on the surface of the carrier and the low utilization rate of the active site, overcomes the deficiencies of the prior art, and provides a method for realizing epitaxial growth and high dispersion of the active component on the surface of the catalyst carrier by lattice matching of the carrier and the active component. The active component includes but is not limited to special crystal type noble metal oxides such as RuO2 and PtO2, and the carrier includes but is not limited to rutile TiO2 and Sn x Ti 1-xO2, and mixed metal oxides / doped metal oxides with the same or similar crystal structure as the active component. When the lattice parameters of the active component are similar or completely matched with the carrier, the active component can be combined with the carrier by simple mixing to achieve epitaxial growth of the active component on the carrier surface, thereby achieving high dispersion. This not only helps to evenly distribute the active component on the carrier surface, but also improves its surface availability and chemical activity. The catalyst prepared by this method has high activity and stability, and is suitable for various oxidation-reduction reactions.

[0034] In the implementation of this embodiment: Collect the lattice parameter data of potential active components from the Crystallography Open Database (COD) of the International Union of Crystallography or related scientific literature to obtain the lattice parameter data (such as lattice constants a, b, c, interplanar spacing, etc.) of potential active components (such as RuO2, PtO2, PdO, etc.).

[0035] Example: If the target active component is RuO2, the database query shows that the tetragonal system parameters are a = 4.49 Å and c = 3.11 Å.

[0036] Collect the lattice parameters of the selected carrier by experimental determination (such as XRD, HRTEM) or database query.

[0037] Example: The carrier after calcination is Sn 0.2 Ti 0.8 O2, which is determined by XRD to have a rutile structure with lattice constants a = 4.65 Å and c = 2.98 Å.

[0038] Use materials science software for analysis and comparison, and use Materials Studio or VESTA software to build crystal models of the active component (RuO2) and the carrier (Sn 0.2 Ti 0.8 O2), and visually compare the crystal face matching.

[0039] Example: In the software, simulate the stacking of the RuO2 (110) crystal face and the Sn 0.2 Ti 0.8 O2 (110) crystal face, and observe the matching degree of atomic arrangement.

[0040] Calculate the lattice mismatch rate, formula: Δa / a = |a(active component) - a(carrier)| / a(carrier) Example: RuO2 and Sn 0.2 Ti 0.8The mismatch rate of O2 in the a-axis direction = |4.49 - 4.65| / 4.65 ≈ 3.4% (<6%), which meets the partial lattice matching condition.

[0041] Simulate the epitaxial growth process, use VASP software to simulate the epitaxial growth of RuO2 on Sn 0.2 Ti 0.8 O2 surface, set temperature, pressure and other parameters, observe atomic layer arrangement and interface energy. Output: Simulation results show that RuO2 forms a uniform monolayer on the carrier surface, with low interface energy (-1.2 eV / atom), indicating high stability.

[0042] Calculate the interaction energy, perform density functional theory (DFT) calculations using Quantum ESPRESSO, and analyze the electronic coupling and binding energy of RuO2 and Sn 0.2 Ti 0.8 O2.

[0043] Results: The binding energy is -2.5 eV, confirming strong interaction and the feasibility of epitaxial growth.

[0044] Evaluate the matching degree and select the best active component Analysis: Comparing the simulation data of RuO2 and PtO2, RuO2 has a lower mismatch rate (3.4% vs. 5.1% for PtO2) and better interface stability, so RuO2 is finally selected.

[0045] Based on the preferred results from computer simulation, the catalyst with highly dispersed active components can be prepared in this embodiment by the following steps (taking RuO2 / Sn 0.2 Ti 0.8 O2 preparation as an example): Carrier preparation. A series of Sn 0.2 Ti 0.8 O2 mixed metal oxides are prepared by co-precipitation method. First, dissolve an appropriate amount of tin chloride in 120 ml of deionized water and stir for 2 hours; then, slowly add the corresponding chemical equivalent of tetrabutyl titanate (TBT) to the solution and stir vigorously. After uniform mixing, gradually add ammonium hydroxide at a rate of about 60 drops per minute and continue stirring until the pH = 10. Let the mixture stand for 12 hours, then wash it with deionized water and ethanol for 6 times. Finally, dry the obtained precipitate at 110°C for 12 hours, then calcine it at 550°C for 5 hours to obtain the mixed metal oxide powder.

[0046] Suspension. In the experiments of this chapter, RuO2 nanoparticles were prepared in advance to ensure the full oxidation of the loaded Ru. The specific operation was as follows: 195 mg of RuCl3·H2O was dissolved in an appropriate amount of deionized water and stirred evenly on a magnetic stirrer. Then, 39 mL of a pre-prepared 15% H2O2 solution was added dropwise to the RuCl3 solution while maintaining high-speed stirring during the addition. The resulting solution was then heated in a water bath at 95 °C for 2 hours, stirred, and cooled to obtain a black suspension of RuO2 nanoparticles.

[0047] Weigh 5 g of thoroughly ground and homogeneous carrier powder and add it to the suspension obtained in the previous step. Stir in a water bath at 50 ℃ for 16 hours. Then transfer the resulting solution to a round-bottom flask and evaporate under reduced pressure using a rotary evaporator to obtain a catalyst precursor uniformly loaded with RuO2 nanoparticles. Dry the precursor at 150 ℃ in air for 16 hours to obtain a solid powder. Wash the obtained solid powder repeatedly with deionized water and anhydrous ethanol until no precipitate forms when the filtrate is added dropwise to AgNO3 solution (after thorough washing). -1 The obtained sample was then dried for 12 hours, thoroughly ground, and calcined at 450 °C in air for 16 hours to obtain catalyst powder with a theoretical mass fraction of 2.5% for the active component RuO2. The catalyst powder was then pressed into tablets, ground, and sieved to obtain 40-60 mesh particles.

[0048] Catalytic performance evaluation of the catalyst. The feed flow rate was controlled at 75 mL / min. -1 At a volumetric rate of [value missing], the feed consisted of 1000 ppm DCM and 20% O2, with N2 used to maintain equilibrium. 200 mg of 40-60 mesh particulate catalyst was charged into the reactor at a mass hourly space velocity (HHSV) of 22500 mL·g⁻¹. -1 ·h -1 The concentrations of DCM and other products in the effluent were measured using Gasmet.

[0049] Sn was prepared by co-precipitation method using tin-titanium doping. 0.2 Ti 0.8 O2 carrier, and loaded with RuO2. Through Figure 1 XRD characterization results revealed no new signals for the catalyst sample with RuO2 supported on the rutile support. This is because RuO2 is highly dispersed on the surface of the rutile support. Figure 2The EDS-Mapping characterization results show that the Anatase-TiO2 support and the RuO2 crystal lattice mismatch, leading to the RuO2 agglomerate growth on its surface, causing a large number of exposed TiO2 surface. The characterization results reveal that the lattice mismatch degree of RuO2 and the support oxide is the key factor to regulate its agglomerate growth and epitaxial growth on the support surface, realizing the highly dispersed RuO2 on the Sn 0.2 Ti 0.8 O2 support surface. The Anatase-Sn 0.2 Ti 0.8 O2 mixed metal oxide with a high active surface suitable for the epitaxial growth of RuO2 is constructed, and a series of catalysts for common redox reactions (such as CVOCs catalytic removal, CO oxidation, etc.) are prepared by this site controllable distribution preparation method, which expands the application potential of catalysts in various redox reactions, promotes the green development of energy conversion, environmental protection and sustainable chemical industry.

[0050] Example 2 Based on the preferred results simulated by the computer, the active component highly dispersed catalyst controllable preparation method in this embodiment mainly includes the following steps: taking Sn 0.2 Ti 0.8 O2 as the support, first loading H2PtCl6 by the impregnation method to prepare Pt / Sn 0.2 Ti 0.8 O2, and then loading RuCl3 by the second impregnation method to prepare Pt-Ru / Sn 0.2 Ti 0.8 O2 bimetallic catalyst. Since Sn 0.2 Ti 0.8 O2 has a good lattice matching relationship with Pt and Ru, a highly dispersed Pt-Ru nanostructure with a synergistic effect is formed after subsequent reduction treatment, Figure 3 The EDS-Mapping characterization results show that the Pt-Ru dispersion is good, and there is a good matching degree between the support. The highly dispersed active component thus improves the CO oxidation.

[0051] Example 3 Based on the preferred results simulated by the computer, the active component highly dispersed catalyst controllable preparation method in this embodiment mainly includes the following steps: First, the Pt@Ru core-shell nanoparticles are prepared by the reduction method: taking H2PtCl6 as the precursor, the Pt nanocore is synthesized under the reduction condition of NaBH4, and then the Ru shell layer is coated on the surface to form the Pt@Ru core-shell structure. Then the Pt@Ru nanoparticles are loaded on the pre-synthesized Sn 0.2 Ti 0.8The O2 carrier is dried and calcined to obtain the catalyst. Figure 4 The EDS-Mapping characterization results show that, due to the Pt@Ru and Sn 0.2 Ti 0.8 The Pt@Ru and Sn O2 have a good lattice matching relationship, which can promote the metal nanoparticles to form a uniform distribution and stable combination of epitaxial structure on the surface of the carrier, thereby realizing high dispersity and excellent interface stability. The catalyst is suitable for various redox reactions and has high catalytic activity and thermal stability.

[0052] The above description of the embodiments is for the purpose of enabling one of ordinary skill in the art to understand and use the application. It will be apparent to those skilled in the art that various modifications can be made to the embodiments and the general principles described herein can be applied to other embodiments without departing from the scope of the application. Thus, the present application is not intended to be limited to the embodiments described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A process for the controllable preparation of a catalyst with a high dispersion of active components, characterized in that The active component is epitaxially grown and highly dispersed on the surface of the carrier by lattice matching, specifically including: S1, a metal oxide with adjustable lattice constant and stable structure or a solid solution thereof is selected as the carrier, the metal oxide is selected from Sn 0.2 Ti 0.8 O2, In x Ti 1-x O2, CeO2-ZrO2, one of them, x is 0.01-0.99, the carrier is prepared by one of hydrothermal method, sol-gel method, coprecipitation method and is calcined into shape; S2, determining the lattice parameters of the carrier after calcination and molding by XRD or HRTEM as reference information for selecting the active component; S3, selecting the active component based on the reference information, the active component including at least one of noble metal nanoparticles, noble metal single atoms, and bimetallic alloys; S4, impregnating, hydrothermal, or vapor deposition of the active component and the carrier, and using the effect of lattice matching to promote the active component to form a uniform epitaxial growth layer on the surface of the carrier, thereby achieving high dispersion of the active component, and obtaining a catalyst product through post-processing; Wherein, the active component can form a metal active site with the carrier lattice matching.

2. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 1, characterized in that, In S3, the specific process of selecting the active component based on the reference information includes: Analyzing the lattice parameters of the preselected active component to obtain the crystal structure and size information of the active component; Comparing the lattice parameters of the active component with the lattice parameters of the carrier after calcination and molding, and selecting the active component with matching lattice parameters with the carrier after calcination and molding, so that the active component can effectively epitaxially grow and highly disperse on the surface of the carrier.

3. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 2, characterized in that, The specific process of selecting the active component with matching lattice parameters with the carrier after calcination and molding includes: Obtaining the lattice parameter data of the preselected active component; Using material science software analysis, XRD characterization technology to compare the crystal structure and lattice parameters of the active component and the carrier after calcination and molding; Comparing the lattice parameters of the active component and the carrier after calcination and molding, calculating the lattice mismatch rate, i.e. Δa / a, where Δa is the difference between the lattice parameters of the active component and the carrier, and a is the lattice parameter of the carrier; Using simulation software to simulate the epitaxial growth process of the active component on the surface of the carrier to predict its dispersibility and interaction; Using density functional theory software to calculate the interaction energy between the active component and the carrier to predict the possibility and stability of epitaxial growth; Based on the analysis, simulation and calculation results, the matching degree of different active components and carriers is evaluated, and the best active component is selected.

4. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 3, characterized in that, In the process of obtaining the lattice parameter data of the preselected active component, the lattice parameter data of the active component is obtained from the Crystallography Open Database of the International Union of Crystallography or scientific and technological literature; The material science software includes one of Materials Studio, CrystalMaker, and VESTA; Using VASP or Quantum ESPRESSO simulation software to simulate the epitaxial growth process of the active component on the surface of the carrier.

5. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 3, characterized in that, The matching degree of different active components and carriers includes: Complete lattice matching: the lattice constant of the carrier and the active component is close, and no lattice distortion occurs at the interface; Partial lattice matching: the lattice constants of the two materials are not completely the same, but the mismatch rate is less than 6%.

6. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 3, characterized in that, The specific process of using simulation software to simulate the epitaxial growth process of the active component on the surface of the carrier to predict its dispersibility and interaction includes: The atomic structure model of the carrier surface and the crystal structure model of the active component are constructed, and then the parameter conditions required for simulation are set. The whole process of adsorption, migration and finally nucleation and assembly of active component atoms or molecules on the carrier surface is simulated by using molecular dynamics method or Monte Carlo method. The uniformity of the dispersion of the active component on the carrier surface and the interaction between them are evaluated by analyzing the position distribution, coordination environment and evolution of the system energy of the active component atoms in the simulation results; The specific process of predicting the possibility and stability of epitaxial growth by calculating the interaction energy between the active component and the carrier through the density functional theory software includes: A periodic supercell calculation model containing the active component and the carrier interface is constructed. The geometric structure of the model is optimized until the total energy of the system converges to a set threshold. Then the total energy of the interface system, the energy of the isolated carrier and the energy of the isolated active component are calculated respectively. The relationship between the three is that the interface interaction energy is equal to the total energy of the system minus the energy of the carrier and then minus the energy of the active component. The negative value of the interaction energy indicates that the combination is stable. The larger the absolute value, the more likely the epitaxial growth occurs and the more stable the structure is.

7. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 3, characterized in that, Based on the analysis of the simulation and calculation results, the matching degree of different active components and carriers is evaluated, and the specific process of selecting the best active component includes: Compare the lattice mismatch rate values between each candidate active component and the carrier. Components with a mismatch rate lower than 6% are selected as primary candidates. Then, considering the dispersion index predicted by molecular simulation, including the surface coverage of the active component and the particle size distribution, and the interaction energy calculated by density functional theory, based on the set selection criteria, the active component with a more negative interaction energy value, i.e. stronger combination, and which can form a uniformly dispersed structure according to simulation, is selected as the final selection.

8. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 1, characterized in that, In S4, the active component and the carrier are combined by one of impregnation, hydrothermal and vapor deposition, and the effect of lattice matching is used to promote the active component to form a uniform epitaxial growth layer on the carrier surface. The specific process includes: Mix the precursor solution of the active component with the carrier powder. Control the temperature and reaction time during impregnation, hydrothermal or vapor deposition to promote the active component to form a uniform epitaxial growth layer on the carrier surface. The effect of lattice matching enables the active component to be uniformly distributed on the carrier surface, forming a highly dispersed structure, thus obtaining the catalyst precursor structure.

9. A process for the controlled preparation of a catalyst with a high dispersion of active components according to claim 8, characterized in that, The process of controlling the temperature and reaction time during impregnation, hydrothermal or vapor deposition includes: Temperature control: The temperature of the active component precursor solution is controlled in the range of 40-150°C by water bath to ensure uniform dispersion of the active component; Reaction time: The reaction time of impregnation, hydrothermal, vapor deposition and other methods is controlled in the range of 5-25 hours to ensure sufficient contact and mixing of the active component and the carrier, while avoiding excessive reaction leading to agglomeration of the active component.

10. The process for the controlled preparation of a catalyst with highly dispersed active components according to claim 1, characterized in that, The post-treatment process includes any one or more of drying, washing, drying, reduction, calcination, tabletting, grinding and sieving.

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