A hollow nanospherical copper borate material, a preparation method and application thereof

Abstract

The present invention belongs to the field of electrocatalysis technology, and specifically relates to a hollow nano-spherical copper borate material and its preparation method and application. The present invention forms a hollow structure by self-assembly of two-dimensional nanosheets, with a specific surface area of ​​20-100 m 2 / g, with a total pore volume of 0.3~0.6 cm 3 / g; the particle size of the hollow nanosphere particles is 5~8μm, which significantly increases the specific surface area and the exposure of active sites, solves the defects of the existing preparation method, and the application of the prepared hollow nanosphere copper borate material in the electroreduction of furfural has achieved a breakthrough in the electrocatalytic performance of copper borate materials, with the advantages of high conversion rate, high selectivity and high stability, providing a new catalyst option for the green preparation of furfuryl alcohol and has important industrial application value.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrocatalysis, and particularly relates to a hollow nanospherical copper borate material and a preparation method and application thereof. BACKGROUND

[0002] The information disclosed in the background of the present application is only intended to increase the understanding of the overall background of the present application and should not necessarily be regarded as acknowledging or implicitly suggesting that this information constitutes prior art known to those of ordinary skill in the art.

[0003] In recent years, with the rapid development of photocatalysis and gas sensing technology, based on the special energy band structure of copper borate material, scientists have gradually developed the photocatalytic and sensing properties of copper borate. However, the synthesis method of existing copper borate material seriously restricts the development of its various applications.

[0004] Copper borate (such as Cu3B2O6) is a functional material with copper-based catalytic activity and boron structure stability, but its existing preparation method has obvious defects:

[0005] Solid phase method: high temperature (>600℃) calcination is required, which has high energy consumption and low product purity, and has not been widely used;

[0006] Hydrothermal / solvothermal method: the obtained product has uneven morphology (mixed nanosheet / particle), insufficient crystallinity, less active site exposure, and low batch repeatability;

[0007] Chemical precipitation method: secondary calcination is required, which sacrifices the specific surface area and has high energy consumption.

[0008] In addition, the copper borate material in the prior art is mainly used in the fields of magnetism and tribology, and its electrocatalytic performance has not been fully developed, especially in the field of furfural electro-reduction to prepare furfuryl alcohol, there is no application report of copper borate material. Therefore, developing a new preparation method of copper borate material and exploring its electrocatalytic performance have become an urgent need to break through the application bottleneck of copper borate material. SUMMARY

[0009] In view of the needs of the prior art, the present application aims to provide a hollow nanospherical copper borate material and a preparation method and application thereof. The present application synthesizes a hollow nanospherical copper borate (Cu3B2O6) material by using a hydrothermal method. The hollow nanospherical structure can provide abundant mesoporous and macroporous channels, which can not only enhance the diffusion efficiency of the reactant furfural, but also promote the rapid desorption of the product, thereby having excellent catalytic activity.

[0010] Specifically, the present application provides the following technical solutions:

[0011] The first aspect of the present invention provides a hollow nano-spherical copper borate material, wherein the material is a hollow nano-spherical structure formed by self-assembly of two-dimensional nanosheets; the crystal phase of the material is Cu3B2O6; the specific surface area of ​​the material is 50-100 m 2 / g, with a total pore volume of 0.3~0.6 cm 3 / g; the particle size of the hollow nanospheres is 5~8 μm.

[0012] Preferably, the thickness of the two-dimensional nanosheet is 20-50 nm.

[0013] Preferably, the hollow nano-spherical copper borate material has a multi-level pore structure of mesopores and micropores, wherein the mesopore diameter is 2-38 nm and the micropore diameter is 1-2 nm.

[0014] A second aspect of the present invention provides a method for preparing the above-mentioned hollow nano-spherical copper borate material, specifically comprising: adding a copper salt and an auxiliary agent to a solvent and stirring until completely dissolved to obtain a solution a; adding boric acid to the solvent and stirring until completely dissolved to obtain a solution b; mixing solution a and solution b, performing a hydrothermal reaction, and obtaining the hollow nano-spherical copper borate material through post-treatment.

[0015] Preferably, the copper salt is selected from one or more of copper sulfate, copper acetate, copper nitrate, and copper chloride; and the auxiliary agent is selected from one or more of pyrrole, imidazole, imidazoline, 2-methylimidazole, or thiazole.

[0016] Preferably, the molar ratio of the copper salt, boric acid and auxiliary agent is 1:(10-16):(3-5).

[0017] Preferably, the solvent is deionized water or a mixed solvent of deionized water and ethanol, and the volume ratio of ethanol to deionized water in the mixed solvent is (0-5):1.

[0018] Preferably, the temperature of the hydrothermal reaction is 130-180° C., and the time is 5-12 h.

[0019] Preferably, the post-treatment is to wash the product after the reaction with anhydrous ethanol for 3 to 5 times, and then dry it at 60 to 100° C. for 8 to 12 hours.

[0020] The third aspect of the present invention provides a use of the hollow nano-spherical copper borate material described in the first aspect in the preparation of an electrocatalyst.

[0021] A fourth aspect of the present invention provides a method for preparing furfuryl alcohol by electrocatalytic reduction of furfural, comprising the following steps:

[0022] The hollow nanospherical copper borate material in the first aspect is loaded on a gas diffusion carbon paper as a working electrode; a mercury / mercury oxide (Hg / HgO) electrode is used as a reference electrode, and a platinum sheet electrode is used as a counter electrode, an electrocatalytic reaction is carried out in a 0.8-1.2 mol / L KOH electrolyte at a voltage of-0.15 to-0.4 V vs. RHE, and a reduction electrocatalytic reaction is carried out, so that the furfural is reduced to furfuryl alcohol.

[0023] Preferably, the concentration of the KOH electrolyte is 1 mol / L; and the voltage is-0.2 V vs. RHE.

[0024] The above one or more technical solutions of the present application have the following beneficial effects:

[0025] (1) The hydrothermal method for synthesizing the copper borate material provided by the present application has the advantage of simple operation, and can synthesize the hollow nanospherical copper borate material with uniform morphology.

[0026] (2) The hollow nanospherical copper borate material prepared by the present application has excellent thermal stability, thereby ensuring its stability in the hydrogenation reaction, and the structure of the catalyst does not change before and after the reaction, and has high reusability. In addition, the copper borate material obtained by the present application has a hollow nanospherical structure, which can promote the entry of the furfural molecules and the timely removal of the product furfuryl alcohol molecules. The hollow nanosphere is formed by self-assembly of two-dimensional nanosheets, has a high degree of active site exposure, and is beneficial to accelerate the adsorption and desorption process of the substrate molecules.

[0027] (3) When the hollow nanospherical copper borate material in the present application is used in the hydrogenation conversion reaction of furfural, the conversion rate of furfural reaches 97% and the selectivity of furfuryl alcohol approaches 100% under the condition of-0.2 V vs. RHE voltage and reaction for 4 h. BRIEF DESCRIPTION OF DRAWINGS

[0028] The drawings accompanying the specification of the present application serve to provide a further understanding of the present application, and the schematic embodiments of the present application and the description thereof serve to explain the present application, and do not constitute an improper limitation on the present application.

[0029] Figure 1 The PXRD graph of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0030] Figure 2 The SEM graph of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0031] Figure 3 The SEM graph of a single particle of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0032] Figure 4 TEM image of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0033] Figure 5 Thermogravimetric curve of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0034] Figure 6 Low temperature nitrogen adsorption-desorption curve of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0035] Figure 7 Pore size distribution of the hollow nanospherical copper borate material prepared in Example 1 of the present application;

[0036] Figure 8 PXRD pattern of the commercially purchased copper borate;

[0037] Figure 9 SEM image of the commercially purchased copper borate;

[0038] Figure 10 LSV curve of the hollow nanospherical copper borate material prepared in Example 1 of the present application and the commercially purchased copper borate material of Comparative Example 1;

[0039] Figure 11 Continuous electrolysis cycling performance of the hollow nanospherical copper borate material prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0040] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0041] In order to enable persons skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below in combination with specific embodiments.

[0042] Example 1: This example provides a hollow nanospherical copper borate material and a preparation method

[0043] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary agent and add them to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source and add it to 15 mL of deionized water to obtain solution b; mix solution a with solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol 3 times, and dried at 80°C for 12 h to obtain a blue powder.

[0044] Example 2: The embodiment provides a hollow nanospherical copper borate material and a preparation method

[0045] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary agent and add them to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source and add it to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150 DEG C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol for 3 times, and dried at 80 DEG C for 12 h to obtain a blue powder.

[0046] Example 3: The embodiment provides a hollow nanospherical copper borate material and a preparation method

[0047] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary agent and add them to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source and add it to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150 DEG C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol for 3 times, and dried at 80 DEG C for 12 h to obtain a blue powder.

[0048] Example 4: The embodiment provides a hollow nanospherical copper borate material and a preparation method

[0049] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary agent and add them to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source and add it to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150 DEG C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol for 3 times, and dried at 80 DEG C for 12 h to obtain a blue powder.

[0050] Example 5: The embodiment provides a hollow nanospherical copper borate material and a preparation method

[0051] Take 1.73 mmol of copper nitrate trihydrate and 5.5 mmol of imidazole as an auxiliary to add to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source to add to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol 3 times, and dried at 80°C for 12 h to obtain a blue powder.

[0052] Example 6: The present example provides a hollow nanospherical copper borate material and a preparation method

[0053] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary to add to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source to add to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 8 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol 3 times, and dried at 80°C for 12 h to obtain a blue powder.

[0054] Example 7: The present example provides a hollow nanospherical copper borate material and a preparation method

[0055] Take 1.73 mmol of copper nitrate trihydrate and 7.36 mmol of imidazole as an auxiliary to add to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source to add to 15 mL of deionized water to obtain solution b; mix solution a and solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 8 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol 3 times, and dried at 80°C for 12 h to obtain a blue powder.

[0056] Comparative Example 1:

[0057] The difference between the present comparative example and Example 1 is that the present comparative example purchases a commercial copper borate material (the manufacturer is Jiangsu Shell Chemical Co., Ltd., and the production batch number is 2025052103).

[0058] Comparative Example 2:

[0059] The difference between the present comparative example and Example 1 is that the molar ratio of copper salt to auxiliary in the present comparative example is 1:1, and the specific preparation method is as follows:

[0060] Take 1.73 mmol of copper nitrate trihydrate and 1.73 mmol of imidazole as an auxiliary agent to add to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source to add to 15 mL of deionized water to obtain solution b; mix solution a with solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 6 h; after the reaction is completed, no product is generated.

[0061] Comparative Example 3:

[0062] The difference between this comparative example and Example 1 is that the molar ratio of copper salt to auxiliary agent in this comparative example is 1:6.78, and the specific preparation method is as follows:

[0063] Take 1.73 mmol of copper nitrate trihydrate and 11.73 mmol of imidazole as an auxiliary agent to add to 15 mL of deionized water to obtain solution a; take 22.5 mmol of boric acid as a boron source to add to 15 mL of deionized water to obtain solution b; mix solution a with solution b, stir for 10 min, transfer to a polytetrafluoroethylene reaction kettle, heat to 150°C, and react for 6 h; after the reaction is completed, the reaction kettle is cooled to room temperature, the reaction kettle is opened, washed with anhydrous ethanol 3 times, and dried at 80°C for 12 h to obtain a blue powder. Under this condition, the product has no hollow structure, therefore, the proportion of the auxiliary agent is crucial for the generation of hollow structure.

[0064] Comparative Example 4:

[0065] The difference between this comparative example and Example 1 is that the copper borate material in this comparative example is prepared by a sol-gel method, which is as follows:

[0066] (1) Preparation of precursor: dissolve 10 mmol of copper nitrate trihydrate (Cu(NO3)2·3H2O) in 40 mL of anhydrous ethanol, magnetically stir until completely dissolved to obtain solution a; dissolve 20 mmol of boric acid (H3BO3) in 40 mL of deionized water to obtain solution b; add solution b dropwise to solution a under a stirring rate of 500 rpm to obtain a mixed solution c.

[0067] (2) pH adjustment: add 1 mol / L of ammonia water (NH3·H2O) dropwise to solution c, continuously stir until the system is converted into a blue transparent sol (pH≈8.0).

[0068] (3) Gelation: let the sol stand at room temperature for aging for 24 h to form a blue gel; wash the gel with deionized water 3 times to remove residual ions.

[0069] (4) Drying and grinding: dry the gel in an 80°C oven for 12 h; grind the dried product to obtain a blue copper borate powder.

[0070] Comparative Example 5:

[0071] The difference between this comparative example and Example 1 is that the copper borate material in this comparative example is prepared by a solid phase method, as follows:

[0072] Copper nitrate (5 mmol) and boric acid (20 mmol) were used as raw materials and calcined at 600°C for 2 h to obtain a precursor. The precursor was ground and calcined at 900°C for 2 h to obtain copper borate.

[0073] Experimental Example 1: This experimental example is to determine the structure of the copper borate materials prepared in the embodiment and the comparative example.

[0074] like Figure 1 , which is the PXRD pattern of the copper borate material prepared in Example 1 of the present invention. The results show that the hollow nano-spherical copper borate material prepared by this method is consistent with the copper borate standard card, indicating that a pure phase copper borate material has been successfully prepared.

[0075] like Figures 2-3 As shown in FIG, this is an SEM image of the copper borate material prepared in Example 1 of the present invention. It can be seen from the figure that the material presents a hollow nanosphere morphology, and the three-dimensional hollow nanosphere is assembled from two-dimensional nanosheets, and the diameter of the hollow nanosphere is 5-8 μm.

[0076] like Figure 4 As shown, this is a TEM image of the copper borate material prepared in Example 1 of the present invention. It can also be clearly observed that the material has obvious hollow nanosphere morphology.

[0077] like Figure 5 As shown in FIG. 1 , the thermogravimetric curve of the copper borate material prepared in Example 1 of the present invention under air is shown. As can be seen from the figure, the material can still maintain about 90% of its original weight under the heat treatment condition of 900° C., indicating its excellent thermal stability.

[0078] like Figure 6 As shown in the figure, the low-temperature nitrogen adsorption-desorption curve of the copper borate material prepared in Example 1 of the present invention is a typical type I / IV composite isotherm, indicating that the copper-carbon composite material has multi-level pore characteristics of both micropores and mesopores, and the specific surface area reaches 56 m 2 / g, and the pore volume reaches 0.39 cm 3 / g.

[0079] like Figure 7 , which is the pore size distribution curve of the copper borate material prepared in Example 1 of the present invention. It can be seen that the material has micropores and mesopores, wherein the mesopore diameter is 2-38 nm and the micropore diameter is 1-2 nm.

[0080] likeFigure 8 As shown in FIG. 1, the PXRD pattern of the copper borate material prepared in Example 1 is shown, and the diffraction peak positions of the copper borate material are consistent with those of the copper borate material in Comparative Example 1. However, the diffraction peak intensity of the commercially available copper borate material is significantly lower than that of the copper borate material prepared in Example 1, which indicates that the crystallinity of the copper borate material prepared in Example 1 is higher than that of the commercially available copper borate material.

[0081] As shown in FIG. 2, the SEM image of the copper borate material in Comparative Example 1 is shown, and it can be seen that the commercially available copper borate material is an agglomerate with amorphous morphology. Figure 9

[0082] Example 1: In this test example, the catalytic performance of the hollow nanospherical copper borate material prepared in Examples 1-7 and Comparative Examples 1-5 for the preparation of furfuryl alcohol by hydrogenation of furfural was tested.

[0083] Experimental procedure: First, 5 mg of the material prepared in the examples and comparative examples was added to a mixture of 700 μL of ethanol, 200 μL of Nafion (5 wt.%) and 50 μL of Nafion, and then ultrasonically treated for 30 min to obtain a uniformly dispersed solution; then, 200 μL of the dispersion was transferred into an airbrush, which was uniformly sprayed onto a 1 cm x 1 cm gas diffusion carbon paper, and after drying, the catalytic material was obtained.

[0084] The electrocatalytic hydrogenation of furfural was carried out in a standard three-electrode system H-type electrolytic cell at room temperature, and the prepared catalyst electrode was separated by a Nafion 117 membrane in the middle of the H-type electrolytic cell. The platinum sheet was used as the counter electrode, and the mercury / mercury oxide (Hg / HgO) electrode was used as the reference electrode, and the electrolyte was 1 M KOH solution. The CHI 760e electrochemical workstation was used to set the constant potential method for the electrolytic hydrogenation of furfural, and the reaction voltage was -0.2 V vs. RHE, and the reaction time was 4 h.

[0085] After the reaction was completed, the reaction solution was taken out, and the product was analyzed by liquid chromatography, and the conversion rate of furfural reduction reaction and the selectivity of the product were calculated according to formula (1-3), wherein the performance results of the electrohydrogenation of furfural to furfuryl alcohol are shown in Table 1.

[0086] Formula (1): Furfural conversion rate (%) = (1- (amount of furfuryl alcohol produced) / (amount of furfural consumed)) x 100%

[0087] Formula (2): Furfuryl alcohol selectivity (%) = (amount of furfuryl alcohol produced) / (amount of furfural consumed) x 100%

[0088] Formula (3): Furfuryl alcohol Faraday efficiency (%) = (amount of furfuryl alcohol produced) / (amount of electrons consumed) x 100%

[0089] Table 1

[0090] ​

[0091] From the comparison of the above electrocatalytic hydrogenation results, it can be seen that the hollow nanospherical copper borate material prepared in the present application has the same diffraction peak (as shown in Figure 8 The present application can successfully prepare copper borate material with high purity. Compared with the commercial copper borate catalyst (Comparative Example 1), the hollow nanospherical copper borate material prepared in the present application has extremely high reactivity in the electrocatalytic reduction of furfural to furfuryl alcohol, because the hollow nanospherical structure can significantly promote the adsorption and desorption of reactant and product molecules, and the two-dimensional nanosheet constituting the nanosphere can greatly expose the catalytically active sites. As can be seen from Table 1, the hollow nanospherical copper borate material prepared in Example 1 of the present application has the most excellent electrocatalytic activity of furfural at a voltage of -0.2 V vs. RHE.

[0092] As shown in Figure 10 When the commercial copper borate material is used as a catalyst for the electrocatalytic hydrogenation of furfural, the current density curve only increases slightly after the addition of furfural; when the hollow nanospherical copper borate material is used as a catalyst, the current density curve starts to decrease at a voltage of -0.1 V vs. RHE, and the difference in current density with or without the addition of furfural gradually increases with the increase of voltage, which indicates that the hollow nanospherical copper borate material has excellent electrocatalytic hydrogenation activity of furfural.

[0093] When the amount of the auxiliary agent is small (Comparative Example 2), the solution in the tetrafluoroethylene reaction kettle cannot maintain a suitable alkaline environment, so that the copper borate material cannot be obtained.

[0094] When the amount of the auxiliary agent is large (Comparative Example 3), the alkalinity of the solution in the tetrafluoroethylene reaction kettle is too high, resulting in that the product does not have a hollow nanospherical structure. During the catalytic reaction, the furfuryl alcohol molecules and the furfuryl alcohol molecules cannot migrate to the internal catalytically active sites, so that the effective active sites exposed by the catalyst are less, resulting in poor catalytic activity.

[0095] Compared with the copper borate material prepared by the sol-gel method (Comparative Example 4), the method used in the present application is simpler, the morphology is more controllable, the particle size is uniform, and has a hollow structure, which greatly promotes the exposure of the effective active sites.

[0096] Compared with the copper borate material prepared by the solid-phase sintering method (Comparative Example 5), the method used in the present application does not need to prepare the copper borate material by high-temperature heating. The solid-phase sintering method mostly has a large particle size and an amorphous morphology, which is not conducive to the exposure of the catalytically active sites.

[0097] In addition, the hollow nanospherical copper borate material prepared in Example 1 was subjected to a continuous electrolysis cycle performance test, and the results are shown in Table 2. Figure 11 As shown in Table 2, the hollow nanospherical copper borate material has excellent cycle stability, and the conversion rate of furfural is higher than 90% and the selectivity of furfuryl alcohol is higher than 95% in 7 cycles.

[0098] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Various modifications and changes can be made by those skilled in the art based on the spirit and principles of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A hollow nanospherical copper borate material, characterized in that, The material is a hollow nanospherical structure formed by self-assembly of two-dimensional nanosheets; the crystal phase of the material is Cu3B2O6; the specific surface area of the material is 50-100 m 2 / g, the total pore volume is 0.3-0.6 cm 3 / g; the particle size of the hollow nanospheres is 5-8 µm.

2. The hollow nanospherical copper borate material of claim 1, wherein, The thickness of the two-dimensional nanosheet is 20-50 nm; the hollow nanospherical copper borate material has a mesoporous and microporous hierarchical pore structure, wherein the mesopore diameter is 2-38 nm and the micropore diameter is 1-2 nm.

3. A method for preparing the hollow nanospherical copper borate material according to any one of claims 1 to 2, characterized in that, Specifically, copper salt and an auxiliary agent are added into a solvent, stirred until completely dissolved to obtain solution a; boric acid is added into a solvent, stirred until completely dissolved to obtain solution b; solution a and solution b are mixed, and a hydrothermal reaction is performed, and the product is obtained after post-treatment. The copper salt is selected from one or more of copper sulfate, copper acetate, copper nitrate and copper chloride; the auxiliary agent is selected from one or more of pyrrole, imidazole, imidazoline, 2-methyl imidazole and thiazole; the molar ratio of the copper salt, boric acid and auxiliary agent is 1:(10-16):(3-5); The solvent is deionized water or a mixed solvent of deionized water and ethanol, and the volume ratio of ethanol to deionized water in the mixed solvent is (0-5):1; The temperature of the hydrothermal reaction is 130-180℃, and the time is 5-12 h.

4. The production method according to claim 3, wherein The post-treatment is to clean the product after reaction with anhydrous ethanol for 3-5 times, and then dry at 60-100℃ for 8-12 h.

5. Application of the hollow nanospherical copper borate material in the preparation of furfuryl alcohol by electrocatalytic reduction of furfural according to any one of claims 1-2.

6. A method for electrocatalytic reduction of furfural to furfuryl alcohol, characterized by, The steps include: The hollow nanospherical copper borate material according to any one of claims 1-2 is loaded on a gas diffusion carbon paper as a working electrode; A mercury / mercury oxide electrode is used as a reference electrode, and a platinum sheet electrode is used as a counter electrode, and the electrocatalytic reaction is carried out in a 0.8-1.2 mol / L KOH electrolyte at a voltage of-0.15 to-0.4 V vs. RHE, and the reduction electrocatalytic reaction is carried out to reduce furfural to furfuryl alcohol.

7. The method of claim 6, wherein, The concentration of the KOH electrolyte is 1 mol / L; and the voltage is-0.2 V vs. RHE.

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