A method for rapidly preparing CuAg bimetallic catalyst by inductive heating and electrocatalytic hydrogenation of 5-hydroxymethylfurfural / 5-chloromethylfurfural

Abstract

This invention discloses a method for the rapid induction thermal preparation of CuAg bimetallic catalysts and the electrocatalytic reduction of 5-hydroxymethylfurfural (HMF) and 5-chloromethylfurfural (CMF) to 2,5-furandiethanol (BHMF). Using copper foam as a substrate, silver nanodendrons are grown in situ via a displacement reaction, followed by short-time thermal shock treatment with induced current to obtain a CuAg-IH catalyst rich in non-equilibrium oxygen vacancies. This catalyst forms an Ag-CuOv dual-site synergistic structure, enabling efficient reduction of high-concentration HMF. The BHMF Faradaic efficiency is close to 100% at low overpotentials, and the cycling performance is stable. It can convert chlorinated CMF substrates, is resistant to chloride ion corrosion, and achieves a BHMF yield of 86.76%. This invention features short preparation time, excellent catalytic activity and substrate tolerance, and has promising prospects for industrial application.

Description

Technical Field

[0001] This invention belongs to the field of biomass electrocatalytic conversion catalyst technology, specifically relating to a method for rapidly preparing oxygen-vacancy-rich CuAg bimetallic catalysts by induction thermal shock, and an application method of the catalyst for electrocatalytic reduction of 5-hydroxymethylfurfural (HMF) and 5-chloromethylfurfural (CMF) to prepare 2,5-furandiethanol (BHMF). Background Technology

[0002] 5-Hydroxymethylfurfural (HMF), an important biomass platform molecule derived from lignocellulose, has significant application potential in high-value chemical processing and renewable polymer fields when catalytically reduced to 2,5-furandiethanol (BHMF). 5-Chloromethylfurfural (CMF) is also an important biomass platform molecule that can be converted into high-value chemicals through electrocatalytic reduction. Electrocatalytic hydrogenation (ECH) using water as a hydrogen source offers advantages such as low energy consumption and mild reaction conditions, providing an environmentally friendly green solution for the high-value utilization of biomass.

[0003] However, while neutral electrolytes such as phosphate-buffered saline (PBS) can prevent the self-polymerization of high-concentration HMF, the extreme scarcity of free protons in neutral media leads to sluggish water dissociation kinetics, severely limiting the efficiency of electrocatalytic hydrogenation reactions. Copper-based catalysts are widely used due to their specific adsorption and activation capabilities for water and carbonyl-containing compounds, but in neutral electrolytes, the water dissociation activation barrier on the surface of pure Cu catalysts is high, making it difficult to supply active hydrogen species; furthermore, under relatively negative overpotentials, a violent competitive hydrogen evolution reaction (HER) is triggered, reducing the Faraday efficiency and yield of the target reduction product.

[0004] Silver (Ag), as a metal that can promote the dissociation of interfacial water and accelerate the generation of active hydrogen, is an effective method for enhancing the electrocatalytic reduction activity of HMF when introduced into a copper substrate. However, when Ag is introduced into a Cu substrate through conventional physical or chemical deposition, it is often limited by poor interfacial contact and electron transfer barriers, resulting in the inefficient participation of the active hydrogen generated at the interface in the hydrogenation reaction of the substrate. In the traditional slow heating process of a tube furnace to prepare CuAg catalysts, Cu is easily deeply oxidized to form inactive CuO, and low-valence Cu... + The low proportion of the (Cu2O) active phase limits its catalytic performance. Currently, there is a lack of CuAg bimetallic catalytic systems that can simultaneously adapt to high concentrations of HMF and chlorine-containing CMF substrates, and possess high activity, high selectivity, and long-term cycling stability. Summary of the Invention

[0005] Addressing the challenges of uncontrollable interface structure, poor hydrogenation kinetics in neutral media, deactivation at high substrate concentrations, and Cl... -To address the shortcomings of poor corrosion resistance, time-consuming preparation, and easy formation of inert CuO, this invention provides a method for rapid induction thermal preparation of CuAg-IH bimetallic catalysts. This method constructs an Ag-Cu2O dual-site heterostructure rich in non-equilibrium oxygen vacancies through millisecond-level thermal shock. Simultaneously, it provides a complete process for the electrocatalytic reduction of HMF and CMF to prepare BHMF using this catalyst, solving the industry pain points of slow water dissociation in neutral systems, low substrate concentration tolerance, and chlorine corrosion deactivation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In one embodiment, the present invention provides a method for rapid induction thermal preparation of CuAg bimetallic catalyst, comprising the following steps: S1. Pretreatment of copper foam: The copper foam substrate is ultrasonically cleaned sequentially with hydrochloric acid solution, deionized water and ethanol, and dried to obtain pretreated copper foam; S2. Replacement growth of Ag dendrites: The pretreated copper foam obtained in step S1 is placed in an aqueous solution containing silver ions, and Ag nano-dendrites are grown in situ on the surface of the copper foam through a replacement reaction to obtain a CuAg precursor; S3. Rapid induction thermal treatment: The CuAg precursor obtained in step S2 is placed at the center of an induction coil, and an induced current is applied for rapid heating, so that the Ag nano-dendrites melt and reconstruct into a highly interconnected defect structure under thermal shock, and are naturally cooled to room temperature to obtain a CuAg-IH bimetallic catalyst rich in non-equilibrium oxygen vacancies.

[0008] In another embodiment, in step S2 of the present invention, the aqueous solution containing silver ions is an aqueous solution of silver nitrate, the concentration of silver nitrate is 50-200mM, the displacement reaction time is 10-60min, and the reaction temperature is room temperature; in step S3, the induction current is 150-450A, the heating time is 10-60s, and the induction coil has 2-5 layers and an inner diameter of 2-6cm.

[0009] In another embodiment, in step S2 of the present invention, the aqueous solution containing silver ions is selected from any one or more combinations of aqueous solutions of silver nitrate, silver acetate, silver perchlorate, or silver sulfate. The displacement reaction is carried out at room temperature and in the dark, and the morphology and loading of Ag nanodendritic crystals are controlled by adjusting the concentration of silver ions and the reaction time.

[0010] In another embodiment, in step S1 of the present invention, the concentration of the hydrochloric acid solution is 0.5-2M, the ultrasonic cleaning time is 5-30 min, the ultrasonic cleaning time of ethanol is 5-20 min, the drying method is vacuum drying or oven drying, and the drying temperature is 40-80℃; the specific surface area of ​​the foamed copper is 1-10 m². 2 / g has a three-dimensional interconnected channel structure.

[0011] In another embodiment, in step S3 of the present invention, the rapid induction heat treatment is carried out in air or an inert atmosphere, with a thermal shock rate of 50-500℃ / s. The thermal shock causes abundant non-equilibrium oxygen vacancies to be formed instantaneously at the material surface interface, while simultaneously stripping oxygen atoms from the crystal lattice, inhibiting the deep oxidation of Cu2O to catalytically inert CuO, and stabilizing the copper active centers in Cu. 0 Mixed valence state with Cu+.

[0012] In one embodiment, the present invention provides a CuAg-IH bimetallic catalyst prepared by the method described in the present invention; the catalyst uses copper foam as a substrate, and the surface has a Cu2O phase rich in non-equilibrium oxygen vacancies and Ag nanoparticles, with Ag and Cu2O forming a rapid mass transfer heterogeneous interface at the nanoscale; Ag exists stably in a single metallic state, serving as an active center for hydrogen production through water dissociation; Cu exists in Cu... 0 and Cu + Mixed valence states exist, in which Cu + The phase serves as the substrate's activated electrophilic center.

[0013] In another embodiment, the oxygen vacancy concentration on the catalyst surface of the present invention accounts for 15%-40% of the total oxygen species, the Ag nanoparticles have a particle size of 20-200 nm, and form a close, non-planar contact with the Cu₂O crystal plane at the nanoscale, constituting an Ag-CuOv spatially decoupled dual-site synergistic structure, wherein the Ag sites are active centers for water dissociation and hydrogen production, and the Cu₂O₂ crystal planes form a synergistic structure with two spatially decoupled sites. + / Oxygen vacancy sites serve as electrophilic activation centers for the carbonyl groups of substrates.

[0014] In one embodiment, the CuAg-IH bimetallic catalyst of the present invention is used in the electrocatalytic reduction of 5-hydroxymethylfurfural to prepare 2,5-furandiethanol. A three-electrode system is constructed with the catalyst as the working electrode. A platinum sheet is selected as the counter electrode, an Ag / AgCl electrode is selected as the reference electrode, a 0.5M phosphate buffer is used as the electrolyte, the initial HMF concentration is 50-200mM, the applied potential is -0.25V to -0.45V, and the electrolysis temperature is room temperature.

[0015] In another embodiment, the present invention achieves HMF conversion, BHMF yield, and Faraday efficiency close to 100% within a potential range of -0.25V to -0.30V; under high concentration HMF conditions of 100-200mM, the BHMF yield remains above 90%; and after 20 consecutive electrolysis cycles, the Faraday efficiency and yield of BHMF remain above 95%.

[0016] In one embodiment, the present invention provides the application of the CuAg-IH bimetallic catalyst in the electrocatalytic reduction of 5-chloromethylfurfural (CMF) to prepare high-value chemicals, comprising the following steps: a. CMF substrate pretreatment: dissolving the CMF sample in boiling deionized water, heating in a constant temperature oil bath at 100-120℃ for 30-60s, and immediately cooling in an ice-water bath. After cooling, adding the buffer salts required for preparing 0.5M PBS according to the stoichiometric ratio, and stirring to dissolve to obtain a PBS precursor dispersion; b. Electrocatalytic reduction: constructing a three-electrode system with the catalyst as the working electrode, using the PBS precursor dispersion obtained in step a as the electrolyte, wherein the CMF concentration is 5-20mM, the applied potential is -0.15V to -0.35V, and the electrolysis temperature is room temperature; the BHMF yield reaches more than 80% at -0.30V, and maintains stability in a Cl--containing system for 10 consecutive cycles.

[0017] Compared with existing technologies, this invention has the following outstanding technical advantages:

[0018] (1) The present invention has high preparation efficiency: through a rapid induction heating strategy, the catalyst can be prepared within minutes. Compared with the disadvantage of the traditional tube furnace and other long-term slow heating process, which easily leads to deep oxidation of the copper substrate and the formation of catalytically inert CuO, thermal shock can not only greatly suppress Cu 2+ Excessive generation, precisely stabilizing the active center in a low-valence Cu with extremely high activity. + The (Cu2O) phase can also utilize thermal shock to melt and reconstruct the originally sharp Ag nanodendritic crystals at the microscale.

[0019] (2) The present invention features dual-site oxygen vacancy synergistic catalysis: a large number of non-equilibrium oxygen vacancy constructs spatially decoupled dual active sites: the Ag site significantly reduces the water dissociation energy barrier in neutral medium and generates active hydrogen in high flux; the oxygen-containing Cu2O specifically polarizes the substrate C=O, and the two work together to significantly improve hydrogenation kinetics and significantly reduce the Tafel slope.

[0020] (3) The present invention has ultra-high substrate concentration tolerance: it can be adapted to 200mM industrial-grade high concentration HMF, and the BHMF yield and Faraday efficiency are maintained at over 95%; the performance does not significantly decrease after 20 cycles.

[0021] (4) This invention is resistant to chlorine corrosion and compatible with CMF substrates: the matching high-temperature dissolution and rapid cooling pretreatment process for CMF solves the problem of poor CMF solubility; the CuAg-IH heterostructure and oxygen vacancy structure resist Cl - Adsorption and poisoning were applied, and the catalytic performance remained stable after 10 cycles, with the highest BHMF yield reaching 86.76%.

[0022] (5) The electrochemical active area of ​​the present invention is greatly improved: the induced thermal shock exposes abundant defect active sites, the double layer capacitance is 3 times that of conventional CuAg catalyst, and the number of reactive active sites is significantly increased. Attached Figure Description

[0023] Figure 1 The following is a schematic diagram of the preparation process and morphological characterization diagram of the CuAg-IH catalyst in this embodiment of the invention: Figure 1 a is a schematic diagram of the catalyst preparation process, showing, in sequence, a copper foam substrate, a CuAg precursor after replacing Ag dendrites, and a CuAg-IH catalyst after induction heat treatment at 350A / 30s; accompanied by SEM morphology images of different stages, showing the original copper foam framework, dendritic Ag, and the morphology of reconstructed interconnection defects in CuAg-IH. Figure 1 b shows the LSV curves of samples treated with different induced currents, comparing the catalyst current densities at 150A, 250A, 350A, and 450A heat treatments. Figure 1 c represents the LSV polarization curves of four catalysts: pure Cu, untreated CuAg, conventionally treated CuAg-H, and CuAg-IH of the present invention, after the addition of HMF. Figure 1 d represents the temperature-time curve during the 350A induction heat treatment process, reflecting the characteristics of instantaneous thermal shock heating. Figure 1 e represents the XRD patterns of Cu, CuAg, CuAg-H, and CuAg-IH samples, verifying the Cu, Ag, and Cu2O phases. The Cu2O characteristic peak intensity of CuAg-IH is significantly enhanced. Figure 1 f and g are HRTEM high-resolution images of the CuAg-IH catalyst; Figure 1 h and i are SEM and EDS elemental mapping images, showing that Cu, Ag, and O elements are uniformly distributed on the catalyst surface.

[0024] Figure 2 XPS characterization of the electronic structure of the catalyst surface in this invention: Figure 2 a shows the O 1s spectra of four groups of samples: Cu, CuAg, CuAg-H, and CuAg-IH. The CuAg-IH sample shows a significant defect oxygen characteristic peak, indicating the generation of a large number of oxygen vacancies. Figure 2 b is the Ag 3d XPS spectrum, confirming that Ag is present in all samples as Ag. 0 The elemental state exists stably. Figure 2 c represents the Cu 2p XPS spectrum, and Cu in CuAg-IH is... 2+ The satellite peak intensity is significantly reduced, indicating a low content of inert CuO. Figure 2 d is the Cu LMM Auger spectrum, and the main peak of CuAg-IH corresponds to Cu2O (Cu + ), proving low-priced Cu + It is the main active copper species;

[0025] Figure 3 The electrocatalytic performance test spectrum of this invention is as follows: Figure 3 a is the LSV comparison curve of pure Cu, CuAg, CuAg-H, and CuAg-IH with or without 50mMMHMF; Figure 3 b is a histogram of the Tafel slope fitting for the four catalysts; Figure 3 c is the fitting curve of the double-layer capacitance; Figure 3 d represents the XANES spectrum of synchrotron radiation; Figure 3 e is a bar chart of HMF conversion, BHMF yield, and Faraday efficiency at different potentials; Figure 3 f represents the catalytic performance at different HMF concentrations of 50 / 100 / 200mM; Figure 3 g represents the LSV curve of CuAg-IH electrolyte with and without 10mM pretreated CMF; Figure 3 h is a bar chart showing the CMF electrocatalytic BHMF yield versus Faraday efficiency at different potentials; Figure 3 i represents the CMF cyclic stability curve; Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; the materials and reagents used are commercially available unless otherwise specified; and the experimental conditions are conventional conditions in the art.

[0027] Example 1: Preparation of CuAg-IH bimetallic catalyst rich in non-equilibrium oxygen vacancies

[0028] This embodiment fully implements the catalyst preparation process of the present invention. This embodiment corresponds to the appendix... Figure 1 (a) Appendix Figure 1 (d)

[0029] 1. Pretreatment of copper foam substrate (S1)

[0030] The copper foam was cut into 1cm×1cm samples and ultrasonically cleaned in 1mol / L hydrochloric acid solution for 15min to remove the original oxide layer on the surface. Then, it was ultrasonically cleaned with deionized water and anhydrous ethanol for 10min each. After cleaning, it was dried in an oven to obtain the pretreated copper foam.

[0031] 2. Ag nanodendritic substitution growth (S2)

[0032] Measure 10 mL of 100 mmol / L silver nitrate aqueous solution and place it into the dried copper foam sample. Let it stand at room temperature for 30 min to carry out the displacement reaction. Relying on the potential difference between copper and silver ions, Ag nanodendritic crystals are grown in situ on the surface of the copper foam skeleton to obtain the CuAg precursor.

[0033] 3. Rapid induction thermal shock treatment (S3)

[0034] The CuAg precursor was placed in the center of a 3-layer induction coil with an inner diameter of 4 cm, and heated for 30 seconds by an induced current of 350 A. The instantaneous thermal shock caused the sharp Ag nanodendritic crystals to melt and reconstruct into a highly interconnected rough defect structure, while oxygen atoms were stripped from the Cu2O lattice to generate a large number of non-equilibrium oxygen vacancies. After natural cooling to room temperature, the CuAg-IH bimetallic catalyst was obtained.

[0035] Example 2: Characterization of catalyst phase, microstructure and electronic structure

[0036] The CuAg-IH catalyst prepared in Example 1 was characterized by XRD, SEM, HRTEM, EDS elemental mapping, and XPS. The test results correspond to the attached figures. Figure 1 (e) Appendix Figure 1 (f)-1(i), Appendix Figure 2 (a)-2(d).

[0037] 1. XRD phase characterization (with appendix) Figure 1 e)

[0038] Four samples were tested simultaneously: pure Cu, untreated CuAg, conventionally heat-treated CuAg-H, and the CuAg-IH sample of this invention. The CuAg-IH spectrum simultaneously showed characteristic diffraction peaks of metallic Cu, elemental Ag, and Cu₂O. The Cu₂O diffraction peak intensity was significantly higher than that of the control sample, and there was no obvious inert CuO diffraction signal, proving that the induced thermal shock stably retains the highly catalytically active Cu. + phase of matter.

[0039] 2. Microstructure and elemental distribution (see appendix) Figure 1 f, 1g, 1h, 1i)

[0040] HRTEM images show that the Ag(111) crystal plane and the Cu2O(111) crystal plane are closely bonded, forming a highly efficient heterogeneous interface for mass / charge transfer at the nanoscale; SEM with EDS element mapping shows that Cu, Ag and O are uniformly distributed on the surface of the three-dimensional skeleton of copper foam.

[0041] 3. XPS electronic structure analysis (attached) Figure 2 )

[0042] Appendix Figure 2(a) O 1s spectrum: The characteristic peak intensity of defect oxygen in the CuAg-IH sample is much higher than that in the other three control samples, confirming that induced thermal shock generates a large number of oxygen vacancies at the catalyst surface and interface; Appendix Figure 2 (b) Ag 3d spectrum: Ag in all samples was in the form of Ag 0 It exists stably in its elemental form and can serve as a core site for the production of active hydrogen through water dissociation in neutral media.

[0043] Appendix Figure 2 (c) Cu 2p spectrum, appendix Figure 2 (d) Cu LMM Auger spectrum: CuAg-IH 2+ The intensity of the satellite peaks decreased significantly, and the main peak of the Auger spectrum corresponds to Cu2O (Cu + The amount of inert CuO generated is extremely low.

[0044] Example 3: Preparation of BHMF from high-concentration HMF by CuAg-IH electrocatalytic reduction

[0045] (1) The CuAg-IH catalyst prepared in Example 1 was assembled into a standard H-type cell as the working electrode. The reaction system was tested using a three-electrode configuration, in which a pure platinum sheet was used as the counter electrode and a silver chloride electrode was used as the reference electrode.

[0046] (2) The electrolyte used was 0.5M phosphate buffer solution (PBS) with a pH of 6.7. 5-hydroxymethylfurfural (HMF) substrate was added to the cathode reaction tank in one step.

[0047] (3) As attached Figure 3 As shown in Figure a, the linear sweep voltammetry (LSV) polarization curves confirm that, after further rapid induction heat treatment, CuAg-IH exhibits the largest intercept increase and a significantly enhanced corresponding current density upon the addition of 50 mM HMF. (See attached figure.) Figure 3 Kinetic fitting showed that CuAg-IH had the lowest Tafel slope (212.98 mV dec⁻¹) compared to pure Cu (322.3 mV dec⁻¹) and conventional CuAg (267.29 mV dec⁻¹), significantly promoting the reaction kinetics of hydrogenation reduction. (See attached image) Figure 3 The double-layer capacitance fitting results show that the double-layer capacitance of CuAg-IH (16.19 mF) is nearly three times higher than that of conventional CuAg (5.72 mF), indicating that the induced thermal shock can very effectively expose the electrochemically active area of ​​the catalyst surface.

[0048] (4) As attached Figure 3As shown in the normalized in-situ synchrotron radiation absorption spectrum (XANES) of d, when a negative reaction potential is applied to the system, the Cu K-edge undergoes a significant and anomalous negative shift (moving to the left of the copper foil baseline). This indicates that under external bias, the adjacent highly active Ag sites rapidly promote the rapid injection and saturation enrichment of excess active hydrogen generated by water dissociation (Volmer step) onto the Cu site surface, forming a highly active electron-rich intermediate species (Cu). x- When the cathode bias is removed and the open circuit potential (OCP) is restored, the absorption edge quickly and reversibly returns to its initial position, fully demonstrating its excellent non-destructive dynamic elasticity and phase stability.

[0049] (5) Constant potential electrolysis test results show (e.g.) Figure 3 As shown in e): Operating within a potential range of -0.25V to -0.30V, the conversion of HMF, the yield of the target product 2,5-furandiethanol (BHMF), and the Faradaic efficiency were all close to 100%. Even under high substrate concentration tolerance assessments (such as... Figure 3 As shown in i), the BHMF yield remains at a high level. Figure 3 As shown in f, after 20 consecutive high-intensity repeated cycles, the Faraday efficiency and yield of BHMF did not show a significant decline and remained stable at over 95%.

[0050] Example 4: Electrocatalytic reduction of CMF to prepare BHMF using CuAg-IH coupled CMF pretreatment process

[0051] (1) Accurately weigh 0.0136 g of pure solid 5-chloromethylfurfural (CMF) sample and quickly put it into a glass beaker containing 10 mL of freshly boiled high-purity deionized water. Then, immediately transfer the entire mixture to a constant temperature oil bath device that has been preheated and controlled at 110°C, and heat it continuously for 45 s. Then, quickly remove the entire beaker from the 110°C oil bath and instantly immerse it completely in a prepared ice-water bath for cooling.

[0052] (2) After the pretreatment solution system in the beaker has completely cooled, add the phosphate buffer salt solids required for preparing the standard 0.5M PBS electrolyte to the 10mL pretreatment solution according to the calculated stoichiometric ratio. After thorough stirring and dissolution, the 0.5M PBS precursor substrate dispersion is obtained.

[0053] (3) The freshly prepared pretreated dispersion was injected entirely into the cathode reaction chamber of the H-type electrolytic cell, using the CuAg-IH prepared in Example 1 as the working cathode. The electrolysis temperature was controlled at room temperature. Figure 3As shown in the LSV curve of g CMF, a significant difference in current response occurred after the introduction of a pretreated 10 mM CMF substrate PBS precursor electrolyte. Figure 3 As shown in h, excellent Faraday efficiency and BHMF yield can be obtained from -0.15V to -0.35V (vs. RHE). At -0.3V (vs. RHE), the BHMF yield can reach 86.76%, and the Faraday efficiency is 70.78%. Furthermore, as... Figure 3 As shown in the cyclic electrocatalytic stability curve in i, the Faraday efficiency and yield of the system did not show any significant decline in more than 10 repeated long-cycle reaction tests, demonstrating the excellent resistance of the catalyst to poisoning and corrosion.

[0054] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be defined by the claims.

Claims

1. A method for rapid induction thermal preparation of CuAg bimetallic catalysts, characterized in that, Includes the following steps: S1. Pretreatment of copper foam: The copper foam substrate was ultrasonically cleaned sequentially with hydrochloric acid solution, deionized water and ethanol, and then dried to obtain pretreated copper foam. S2. Replacement growth of Ag dendrites: The pretreated copper foam obtained in step S1 is placed in an aqueous solution containing silver ions, and Ag nano-dendrites are grown in situ on the surface of the copper foam through a replacement reaction to obtain CuAg precursor. S3. Rapid induction heat treatment: The CuAg precursor obtained in step S2 is placed in the center of an induction coil, and an induced current is applied for rapid heating, so that the Ag nanodendritic crystals melt and reconstruct into a highly interconnected defect structure under thermal shock. After natural cooling to room temperature, a CuAg-IH bimetallic catalyst rich in non-equilibrium oxygen vacancies is obtained.

2. The method for rapid preparation of CuAg bimetallic catalyst by induction heating according to claim 1, characterized in that, In step S2, the aqueous solution containing silver ions is an aqueous solution of silver nitrate with a concentration of 50-200 mM, a displacement reaction time of 10-60 min, and a reaction temperature of room temperature; in step S3, the induction current is 150-450 A, the heating time is 10-60 s, and the induction coil has 2-5 layers and an inner diameter of 2-6 cm.

3. The method for rapid preparation of CuAg bimetallic catalyst by induction heating according to claim 1 or 2, characterized in that, In step S2, the aqueous solution containing silver ions is selected from any one or a combination of aqueous solutions of silver nitrate, silver acetate, silver perchlorate, or silver sulfate. The displacement reaction is carried out at room temperature and in the dark. The morphology and loading of Ag nanodendritic crystals are controlled by adjusting the concentration of silver ions and the reaction time.

4. The method for rapid preparation of CuAg bimetallic catalyst by induction heating according to any one of claims 1 to 3, characterized in that, In step S1, the concentration of the hydrochloric acid solution is 0.5-2M, and the ultrasonic cleaning time is 5-30 min; the ultrasonic cleaning time of ethanol is 5-20 min; the drying method is vacuum drying or oven drying, and the drying temperature is 40-80℃; the specific surface area of ​​the foamed copper is 1-10 m². 2 / g has a three-dimensional interconnected channel structure.

5. The method for rapid induction thermal preparation of CuAg bimetallic catalyst according to any one of claims 1 to 4, characterized in that, In step S3, the rapid induction heat treatment is carried out in air or an inert atmosphere, with a thermal shock rate of 50-500℃ / s. The thermal shock causes abundant non-equilibrium oxygen vacancies to instantly form at the material surface and interface, while simultaneously stripping oxygen atoms from the crystal lattice, inhibiting the deep oxidation of Cu2O to catalytically inert CuO, and stabilizing the copper active centers in Cu. 0 With Cu + Mixed valence state.

6. A CuAg-IH bimetallic catalyst, characterized in that, The catalyst is prepared by the method according to any one of claims 1 to 5; the catalyst is based on copper foam, and the surface has a Cu2O phase rich in non-equilibrium oxygen vacancies and Ag nanoparticles, in which Ag and Cu2O form a fast mass transfer heterogeneous interface at the nanoscale; Ag exists stably in a metallogenic state and serves as an active center for hydrogen production through water dissociation; Cu exists as Cu... 0 and Cu + Mixed valence states exist, in which Cu + The phase serves as the substrate's activated electrophilic center.

7. The CuAg-IH bimetallic catalyst according to claim 6, characterized in that, The catalyst surface has an oxygen vacancy concentration of 15%-40% of the total oxygen species. The Ag nanoparticles have a diameter of 20-200 nm and form a close, non-planar contact with the Cu₂O crystal plane at the nanoscale, constituting an Ag-CuOv spatially decoupled dual-site synergistic structure. The Ag sites are active centers for water dissociation and hydrogen production, while the Cu₂O sites are active centers for this purpose. + / Oxygen vacancy sites serve as electrophilic activation centers for the carbonyl groups of substrates.

8. The application of the CuAg-IH bimetallic catalyst according to claim 6 or 7 in the electrocatalytic reduction of 5-hydroxymethylfurfural to prepare 2,5-furandiethanol, characterized in that, A three-electrode system was constructed using the catalyst as the working electrode. The counter electrode was a platinum sheet, the reference electrode was an Ag / AgCl electrode, the electrolyte was a 0.5M phosphate buffer, the initial HMF concentration was 50-200mM, the applied potential was -0.25V to -0.45V, and the electrolysis temperature was room temperature.

9. The application according to claim 8, characterized in that, Within the potential range of -0.25V to -0.30V, the conversion rate of HMF, the yield of BHMF, and the Faradaic efficiency are all close to 100%. Under the condition of high concentration of HMF of 100-200mM, the yield of BHMF is maintained above 90%. After 20 consecutive cycles of electrolysis, the Faradaic efficiency and yield of BHMF remain above 95%.

10. The application of the CuAg-IH bimetallic catalyst according to claim 6 or 7 in the electrocatalytic reduction of 5-chloromethylfurfural (CMF) to prepare high-value chemicals, characterized in that, Includes the following steps: a. CMF substrate pretreatment: Dissolve the CMF sample in boiling deionized water, heat in a constant temperature oil bath at 100-120℃ for 30-60s, and then immediately cool in an ice water bath. After cooling, add the buffer salts required to prepare 0.5M PBS according to the stoichiometric ratio, stir to dissolve and obtain PBS precursor dispersion. b. Electrocatalytic reduction: A three-electrode system was constructed using the catalyst as the working electrode. The PBS precursor dispersion obtained in step a was used as the electrolyte, wherein the CMF concentration was 5-20 mM, the applied potential was -0.15 V to -0.35 V, and the electrolysis temperature was room temperature. At -0.30 V, the BHMF yield reached over 80%, and the reduction was achieved even with Cl-containing... - The system remains stable after 10 consecutive cycles.

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