A high-activity boride-mediated basic hydrogen evolution electrocatalyst, a preparation method and application thereof

Abstract

The application discloses a high-activity alkaline hydrogen evolution electrocatalyst with boride as a medium and a preparation method and application thereof. The electrocatalyst is composed of a metal active phase, a metal oxide active phase, a boron oxide base phase and a carrier, the metal active phase is dispersedly distributed on the surfaces of the metal oxide active phase and the boron oxide base phase, the metal oxide active phase and the boron oxide base phase are mixedly distributed, and both are loaded on the carrier. In the high-temperature heat treatment process, the metal generated by the reduction reaction is combined with the original metal oxide to construct a synergistic catalytic active site; more high-conductivity metals are generated in situ after the heat treatment, thereby ensuring the high conductivity of the catalyst; the construction of the three-dimensional nano structure and a large number of nanopores caused by dehydration of boric acid in the heat treatment process provide more active sites and further improve the mass transfer performance of the catalyst. The catalytic performance of the electrocatalyst is superior to that of a noble metal Pt catalyst, and the electrocatalyst has excellent stability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of hydrogen production and material technology, and particularly relates to a high-activity alkaline hydrogen evolution electrocatalyst taking boride as a medium as well as a preparation method and application thereof. BACKGROUND

[0002] Fossil energy is an important material basis for creating modern human civilization, but by now, fossil energy has gradually become the source of problems restricting the sustainable development of human society. Coupling water electrolysis with primary renewable energy can provide a clean hydrogen production method and an advanced energy conversion technology, which is expected to play an important role in the future clean energy economy. The key to realizing this beautiful vision lies in the development of high-activity and low-cost hydrogen evolution electrocatalytic materials. The noble metal Pt is a recognized high-activity hydrogen evolution reaction catalyst, but its high material cost and resource scarcity seriously restrict its practical application. In recent years, the development of new non-noble metal catalysts has become the mainstream trend in the field of water electrolysis technology, which seeks to reduce material costs while seeking excellent catalytic performance. Thanks to the progress of material preparation and characterization technology and the improvement of computing power, non-noble metal catalysts have made great progress in material composition design, nanostructure regulation, modification mechanism analysis, etc. At present, a variety of Ni-based / Co-based alloys or compounds have shown hydrogen evolution catalytic activity close to noble metal Pt, which has preliminarily confirmed the practical feasibility of obtaining high-performance and low-cost catalysts. However, in general, the catalytic activity of non-noble transition metal electrocatalysts still cannot meet the demand of practical application. The lack of a feasible method to simultaneously solve the problems of catalytic intrinsic activity, active site density and electronic conductivity is still a major challenge to the development of high-performance catalysts. This is especially true for alkaline hydrogen evolution reaction catalysts that require multi-site synergistic action.

[0003] Transition metal borides are considered an important class of electrocatalytic materials due to their excellent metal conductivity, good chemical inertness and unique electronic properties. However, most of the reported transition metal boride catalysts only show mediocre catalytic hydrogen evolution activity. For example, representative Co or Ni-based boride catalysts require a 60-80 mV overpotential to drive 10 mA·cm -2alkaline hydrogen evolution reaction [Adv. Energy Mater. 8 (2018) 1801372; Small 13 (2017) 1700805; Adv. Energy Sustainability Res. 2 (2021) 2100052]. The complex catalyst phase composition and difficult microstructure fine-tuning hinder the development of transition metal borides in the field of water electrolysis. Specifically, most researchers currently choose a simple chemical reduction method to prepare transition metal boride catalysts. However, the transition metal boride prepared by this method is amorphous in nature and is usually entangled with by-products such as boron oxides and metal oxides. This makes it very difficult to accurately characterize the catalyst phase and fine-tune the interface. In addition, the traditional chemical reduction method makes it difficult to control the morphology and microstructure of the catalyst due to its fast reaction kinetics, which further affects its catalytic hydrogen evolution reaction activity. Therefore, it is urgent to find a simple and controllable preparation method that can accurately control the catalyst. SUMMARY

[0004] In view of the shortcomings and deficiencies of the prior art, the primary purpose of the present application is to provide a high-activity alkaline hydrogen evolution electrocatalyst mediated by borides. The catalyst of the present application has high intrinsic activity, abundant active sites and good electrical conductivity, and can efficiently catalyze the water electrolysis hydrogen evolution reaction under alkaline conditions, and its comprehensive catalytic performance is better than that of commercial Pt / C catalyst.

[0005] Another purpose of the present application is to provide a preparation method of the high-activity alkaline hydrogen evolution electrocatalyst mediated by borides. The method has the advantages of easy availability of raw materials, simple operation, controllable reaction and easy mass production.

[0006] Still another purpose of the present application is to provide the application of the high-activity alkaline hydrogen evolution electrocatalyst mediated by borides in water electrolysis for hydrogen production.

[0007] The purposes of the present application are achieved by the following technical solutions:

[0008] A high-activity alkaline hydrogen evolution electrocatalyst mediated by borides, the electrocatalyst is composed of a metal active phase, a metal oxide active phase, a boron oxide matrix phase and a carrier, the metal active phase is dispersedly distributed on the surface of the metal oxide active phase and the boron oxide matrix phase, the metal oxide active phase and the boron oxide matrix phase are mixedly distributed and are both loaded on the carrier.

[0009] Preferably, the metal active phase is a transition metal, the metal oxide active phase is a transition metal oxide; the carrier is selected from a foam metal, a metal mesh, an ion exchange resin, a molecular sieve or a porous carbon material; the transition metal refers to at least one of Fe, Co and Ni.

[0010] Further preferably, the carrier is selected from cobalt foam.

[0011] Preferably, the metal active phase is in the form of nanoparticles with a particle size of 1-10 nm.

[0012] Preferably, the metal oxide active phase and the boron oxide matrix phase are in an amorphous form; the metal oxide active phase and the boron oxide matrix phase have a nanoporous sheet structure with a nanopore size of 2-10 nm, a nanoparticle thickness of 1-10 nm, and a nanoparticle length of 50-500,000 nm.

[0013] The above-mentioned preparation method of the high-activity boride-mediated alkaline hydrogen evolution electrocatalyst includes the following preparation steps:

[0014] (1) adding a carrier material into an aqueous solution containing a transition metal salt, a boron-containing reducing agent, and a complexing agent, and growing a metal boride derivative precursor with a nanostructure on the surface of the carrier material through a reduction reaction;

[0015] (2) washing and drying the metal boride derivative precursor obtained in step (1), and performing high-temperature heat treatment in an inert atmosphere to obtain the high-activity boride-mediated alkaline hydrogen evolution electrocatalyst.

[0016] Preferably, the transition metal salt in step (1) is at least one of halides, nitrate, sulfate, sulfamate, or acetate of the transition metal; and the transition metal is at least one of Fe, Co, and Ni.

[0017] Preferably, the complexing agent in step (1) is C4H4Na2O4 (disodium succinate); and the boron-containing reducing agent is C2H 10 BN (dimethylaminoborane).

[0018] Preferably, the ratio of the total amount of the transition metal salt to the amount of substance of the boron-containing reducing agent is 9:4-36; and the ratio of the total amount of the transition metal salt to the amount of substance of the complexing agent is 9:4-36.

[0019] Further preferably, the ratio of the total amount of the transition metal salt to the amount of substance of the boron-containing reducing agent is 3:4; and the ratio of the total amount of the transition metal salt to the amount of substance of the complexing agent is 3:4.

[0020] Preferably, in the aqueous solution in step (1), the total concentration of the transition metal salt is 0.001-1 M, the concentration of the boron-containing reducing agent is 0.001-1 M, and the concentration of the complexing agent is 0.001-1 M.

[0021] Further preferably, in the aqueous solution of step (1), the total concentration of the transition group metal salt is 0.04-0.5 M, the concentration of the boron-containing reducing agent is 0.04-0.5 M, and the concentration of the complexing agent is 0.04-0.5 M.

[0022] Preferably, the ratio of the area of the carrier material to the total amount of the transition group metal salt in step (1) is 0.01-1 m 2 : 1 mol.

[0023] Further preferably, the ratio of the area of the carrier material to the total amount of the transition group metal salt in step (1) is 0.1-0.5 m 2 : 1 mol.

[0024] Preferably, the temperature of the reduction reaction is 25-90℃, and the time of the reduction reaction is 5-200 min.

[0025] Further preferably, the temperature of the reduction reaction is 50-60℃, and the time of the reduction reaction is 50-100 min.

[0026] Preferably, in step (2), the inert atmosphere is argon, the temperature of the high-temperature heat treatment is 100-500℃, and the time of the high-temperature heat treatment is 1-5 h.

[0027] Further preferably, in step (2), the temperature of the high-temperature heat treatment is 250-350℃, and the time of the high-temperature heat treatment is 1.5-2.5 h.

[0028] The above-mentioned high-activity alkaline hydrogen evolution electrocatalyst mediated by borides is applied in the electrolytic water decomposition for hydrogen production.

[0029] The design principle of the present application is as follows:

[0030] For electrocatalysts, three elements affecting its apparent catalytic activity are intrinsic activity, active site density and electrical conductivity. The traditional electrocatalysts often simply focus on one or two aspects, the catalyst provided by the application optimizes the three elements at the same time in the design idea, and provides a simple and easy to control preparation method to realize it. First, the chemical reduction method is used to grow the metal boride derivative precursor containing the catalyst active component and having high specific surface area on the surface of the carrier material, to lay the material composition and structure foundation for synthesizing high-performance catalyst. Among them, the metal boride derivative precursor is a composite material containing metal boride, metal oxide and boric acid. Then, the precursor is subjected to high-temperature heat treatment in an inert atmosphere. Because the metal boride has a certain reducing property, the metal boride and the metal oxide undergo redox reaction under high-temperature heat treatment in an inert atmosphere to generate metal and boron oxide. On the one hand, the in-situ precipitated metal and the original oxide matrix combine to construct a synergistic catalytic active site, in which the oxide promotes water molecule dissociation and the metal provides hydrogen atom complex desorption active site, and the two synergistically act to improve the efficiency of the alkaline electrolytic water hydrogen evolution reaction. On the other hand, the in-situ precipitation of metal particles ensures the close combination between the metal and the oxide, which is conducive to the transfer of electrons in the electrocatalytic process. At the same time, the conversion of the metal oxide with poor electrical conductivity into metal with better electrical conductivity also improves the electrical conductivity of the catalyst material. In addition, the construction of three-dimensional nanostructure and a large number of nanopores caused by dehydration of boric acid during calcination are conducive to improving the specific surface area of the material, thereby providing more catalytic active sites and ion / gas diffusion channels. In summary, the hydrogen evolution electrocatalyst provided by the application has high intrinsic activity, rich active sites and good electrical conductivity.

[0031] The advantages and beneficial effects of the application are:

[0032] (1) The method and material provided by the application have the characteristics of simultaneously optimizing the three elements of intrinsic activity, active site quantity and electrical conductivity. On the one hand, the metal generated by reduction reaction during calcination heat treatment combines with the original metal oxide to construct a synergistic catalytic active site; on the other hand, the in-situ generation of more high-conductivity metals after calcination heat treatment ensures the high electrical conductivity of the catalyst material; in addition, the construction of three-dimensional nanostructure and a large number of nanopores caused by dehydration of boric acid during calcination provide more active sites and further improve the mass transfer performance of the catalyst.

[0033] (2) The preparation method of the application has the advantages of easy availability of raw materials, simple process, controllable reaction and easy mass production.

[0034] (3) The high-activity alkaline hydrogen evolution electrocatalyst obtained by the application can efficiently catalyze the electrolytic water hydrogen evolution reaction under alkaline conditions, and its catalytic performance is better than that of the noble metal Pt catalyst, and it has excellent stability. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 Scanning electron micrographs of (a) the reduced state sample Co2B / CoO / H3BO3 / CF and (b) the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0036] Figure 2 Transmission electron micrograph of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0037] Figure 3 Aberration-corrected scanning transmission electron micrographs of (a) the reduced state sample Co2B / CoO / H3BO3 / CF and (b) the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0038] Figure 4 X-ray diffraction patterns of the reduced state sample Co2B / CoO / H3BO3 / CF and the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0039] Figure 5 X-ray photoelectron spectrograms of the reduced state sample Co2B / CoO / H3BO3 / CF and the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0040] Figure 6 (a-d) Energy dispersive X-ray spectrograms and (e) Atom resolution electron energy loss spectrogram of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0041] Figure 7 (a) Hydrogen evolution reaction polarization curves and (b) Tafel curves of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1 compared with reference sample CF, reduced state sample Co2B / CoO / H3BO3 / CF and Pt / C.

[0042] Figure 8 (a) Current density versus potential sweep rate and (b) Impedance spectroscopy test results of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1 compared with reference sample CF, reduced state sample Co2B / CoO / H3BO3 / CF and Pt / C.

[0043] Figure 9 Durability test results of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1.

[0044] Figure 10 Scanning electron micrograph of the heat-treated state sample Co / CoO / B2O3 / CF in Example 1 after 100 hours of durability test.

[0045] Figure 11 High resolution transmission electron microscopy image of the heat-treated sample Co / CoO / B2O3 / CF after 100 hours durability test in Example 1.

[0046] Figure 12 (a) Polarization curves of the reduced samples prepared with different precursor salt ratios in Example 2 (b) Polarization curves of the reduced samples prepared with or without complexing agent under the condition of Co salt and boron reducing agent (DMAB) molar ratio of 3:4.

[0047] Figure 13 (a) Polarization curves of the reduced samples prepared with different reduction temperatures in Example 2 (b) Polarization curves of the reduced samples prepared with different reduction times under the reduction temperature of 55°C.

[0048] Figure 14 Polarization curves of the heat-treated samples prepared with different heat treatment temperatures in Example 2.

[0049] Figure 15 Scanning electron microscopy image of the heat-treated sample Co / CoO / B2O3 / NF in Example 3.

[0050] Figure 16 X-ray photoelectron spectroscopy image of the heat-treated sample Co / CoO / B2O3 / NF in Example 3.

[0051] Figure 17 (a) Polarization curves and (b) Durability test results of the heat-treated sample Co / CoO / B2O3 / NF and the reference sample in Example 3.

[0052] Figure 18 (a) Polarization curves and (b) Durability test results of the heat-treated sample Co / CoO / B2O3 / Ti and the reference sample in Example 4.

[0053] Figure 19 (a) Polarization curves and (b) Durability test results of the heat-treated sample Ni / NiO / B2O3 / NF and the reference sample in Example 5.

[0054] Figure 20 (a) Polarization curves and (b) Durability test results of the heat-treated sample Ni-Co / NiO / CoO / B2O3 / NF and the reference sample in Example 6. DETAILED DESCRIPTION

[0055] The present invention will be specifically described below with reference to the embodiments, but the implementation and protection scope of the present invention are not limited to the following embodiments.

[0056] The present invention will be described in detail below through specific embodiments.

[0057] Example 1

[0058] Synthesis, structure and catalytic performance of Co / CoO / B2O3 / CF catalysts

[0059] Catalyst preparation:

[0060] (1) Using cobalt foam (CF) as a carrier, its thickness is 1.80 mm and its areal density is 650 g / m³. 2 The pore size is 0.20–0.80 mm. Cobalt foam (1×2 cm⁻¹) 2 After being ultrasonically cleaned with ethanol for 10 minutes, activated with 1M hydrochloric acid solution for 5 minutes, and ultrasonically cleaned with deionized water for 10 minutes, it was placed in 25 mL of solution containing CoSO4·7H2O (0.12M) and C2H2O. 10 The solution was prepared by placing the deionized aqueous solution of BN (0.16M) and C4H4Na2O4 (0.16M) in a constant temperature water bath at 55°C for 70 min. The CF was then removed, thoroughly washed, and vacuum dried at 60°C for 1 hour to obtain the reduced sample Co2B / CoO / H3BO3 / CF.

[0061] (2) 1×2cm 2 The reduced sample was placed in the center of a quartz boat and heated to 300°C under an argon atmosphere at a heating rate of 2°C / min. After being kept at the same temperature for 2 hours, it was cooled to room temperature to obtain the target catalyst Co / CoO / B2O3 / CF.

[0062] Phase / structure / elemental chemical state characterization of catalysts:

[0063] The scanning electron microscope (SEM) images of the reduced state sample and the heat-treated state sample obtained in this embodiment are as follows: Figure 1 As shown. Scanning electron microscopy revealed that the reduced sample was a three-dimensional network structure formed by nanosheets. Figure 1 (a) After high-temperature heat treatment, the three-dimensional network structure showed no significant change. Figure 1 (b) but transmission electron microscopy observation ( Figure 2 It was discovered that a large number of nanopores were formed on the nanosheets, with a pore size of 2-4 nm.

[0064] Further aberration-corrected scanning transmission electron microscopy (AC-STEM) observations Figure 3 a) It was found that the reduced sample existed in an amorphous state, and the corresponding X-ray diffraction (XRD) analysis ( Figure 4) also confirmed this. In addition, the broadening of the diffraction peak in the XRD pattern corresponding to the strongest diffraction peak of Co2B was also observed, which suggested that the reduced sample contained amorphous Co2B. According to the X-ray photoelectron spectroscopy (XPS) analysis ( Figure 5 ), Co 0 , Co 2+ , B 0 and BO x signals were presented in the reduced sample. Among them, the Co 0 signal was negatively shifted relative to the standard sample, while the B 0 signal was positively shifted relative to the standard sample, which proved the existence of amorphous Co2B alloy in the reduced sample. In addition, according to the reaction principle of the chemical reduction method and the existence of a large amount of Co 2+ and BO x signals in the reduced sample, we finally confirmed that the reduced sample was actually an amorphous mixture containing Co2B, CoO and H3BO3.

[0065] After the reduced sample was subjected to high-temperature heat treatment, the phase composition of the sample changed significantly. According to the XRD analysis ( Figure 4 ), the heat-treated sample presented a weak diffraction peak corresponding to metallic Co. In addition, the existence of metallic Co nanoparticles was also confirmed in the AC-STEM image ( Figure 3 b). Correspondingly, the XPS results ( Figure 5 ) showed that the B 0 signal in the heat-treated sample completely disappeared, and the shift of the Co 0 signal relative to the standard sample also completely disappeared. In addition, the intensity of the Co 0 signal increased relative to the Co 2+ signal. Comprehensive analysis showed that Co2B and CoO underwent redox reaction during high-temperature heat treatment to generate Co and B2O3. Combined with the analysis of the AC-STEM image ( Figure 3 b), energy dispersive X-ray spectroscopy (EDS) ( Figure 6 a, b, c, d) and atomic resolution electron energy loss spectroscopy (EELS) ( Figure 6 e), we finally proved that the heat-treated sample was a composite material of metallic Co nanoparticles mixed with amorphous CoO / B2O3 substrate.

[0066] Electrocatalytic performance test of the catalyst:

[0067] The hydrogen evolution reaction polarization curve test results ( Figure 7 a) showed that the Co2B / CoO / H3BO3 / CF catalyst in the reduced sample required a hydrogen evolution overpotential of 76 mV in 1.0 M potassium hydroxide solution to reach 10 mA / cm 2The target catalyst Co / CoO / B2O3 / CF only needs a hydrogen evolution overpotential of 16 mV to achieve a current density of 10 mA / cm 2 The target catalyst Co / CoO / B2O3 / CF has a much higher catalytic activity than Co2B / CoO / H3BO3 / CF, and even higher than the commercial Pt / C catalyst. Similarly, the Tafel slope of the target catalyst Co / CoO / B2O3 / CF (31 mv / dec) is also better than that of Co2B / CoO / H3BO3 / CF (65 mv / dec) and the commercial Pt / C catalyst (43 mv / dec) Figure 7 b) in the table.

[0068] Figure 8 The current density-potential scan rate relationship diagram of the target catalyst Co / CoO / B2O3 / CF and the reference sample is given in a), compared with the reduced sample Co2B / CoO / H3BO3 / CF, the double-layer capacitance of the target catalyst is increased by more than 2 times, that is, the electrochemical specific surface area is increased by more than 2 times, and the significant increase in the electrochemical specific surface area should be due to the dehydration reaction caused by the decomposition of boric acid during high-temperature heat treatment; according to the impedance spectrum test result Figure 8 b), the resistance of the target catalyst is lower than that of the reduced sample, which should be due to the in-situ generation of more metal Co with high conductivity.

[0069] Figure 9 The stability test results of the target catalyst are given, after 100 hours of constant current measurement, the overpotential of the Co / CoO / B2O3 / CF catalyst at 10 mA / cm 2 is only increased by 7 mV, and the overpotential at 100 mA / cm 2 is only increased by 34 mV, indicating that the catalyst has good stability.

[0070] Figure 10 and Figure 11 The phase / microstructure results of the Co / CoO / B2O3 / CF catalyst after 100 hours of durability test are given, the results show that the morphology and phase structure of the target catalyst are still maintained, in addition, additional Co(OH)2 is observed in the transmission electron microscopy results, which is due to the reaction of the catalyst in the alkaline solution. The comprehensive results show that the catalyst has good stability.

[0071] Example 2

[0072] (1) Catalyst preparation with different proportions of precursor salts:

[0073] In this synthesis method, CoSO4·7H2O and C2H 10The concentration of BN was 0.12M and 0.04M (3:1), 0.12M and 0.48M (3:12), 0.04M:0.16M (1:4), 0.36M; 0.16M (9:4) respectively, and the rest of the preparation conditions were consistent with example 1.

[0074] (2) Catalyst preparation with or without complexing agent:

[0075] In the synthesis method of the present embodiment, no complexing agent C4H4Na2O4 was used, and the rest of the preparation conditions were consistent with example 1.

[0076] (3) Catalyst preparation at different reduction reaction temperatures:

[0077] In the synthesis method of the present embodiment, the water bath temperature of step (1) was 40℃, 70℃, and the rest of the preparation conditions were consistent with example 1.

[0078] (4) Catalyst preparation at different reduction reaction times:

[0079] In the synthesis method of the present embodiment, the reaction time of step (1) was 10min, 40min, 100min, and the rest of the preparation conditions were consistent with example 1.

[0080] (5) Catalyst preparation at different heat treatment temperatures:

[0081] In the synthesis method of the present embodiment, the constant temperature treatment temperature of step (2) was 200℃, 400℃, and the rest of the preparation conditions were consistent with example 1.

[0082] Figures 12-14 The hydrogen evolution reaction polarization curves of the catalysts prepared under different ratios of precursor salt, with or without complexing agent, different reduction reaction temperatures, different reduction reaction times, and different heat treatment temperatures are given, and the results show that the catalyst prepared under the conditions of example 1 has higher catalytic hydrogen evolution activity.

[0083] Example 3

[0084] Synthesis, structure and catalytic performance of Co / CoO / B2O3 / NF catalyst

[0085] Catalyst preparation:

[0086] In the synthesis method of the present embodiment, only the foam cobalt (CF) was replaced with foam nickel (NF), and the rest of the preparation conditions were consistent with example 1.

[0087] Phase / structure / elemental state characterization of the catalyst:

[0088] Scanning electron microscopy observation Figure 15 found that the target catalyst was a three-dimensional network structure formed by nanosheets.

[0089] XPS results show thatFigure 16 The presence of metallic Co, CoO, and B2O3 in the target catalyst proves that the target catalyst is a Co / CoO / B2O3 catalyst supported on nickel foam.

[0090] Electrocatalytic performance testing of catalysts:

[0091] Results of hydrogen evolution reaction polarization curve test ( Figure 17 Figure a) shows that the Co / CoO / B2O3 / NF catalyst exhibits excellent electrocatalytic activity for the hydrogen evolution reaction, requiring only 14 mV of hydrogen evolution overpotential to reach 10 mA / cm² in 1.0 M potassium hydroxide alkaline solution. 2 Current density; 10-hour constant current durability test results ( Figure 17 Figure b) shows that the catalyst activity did not show a significant decline, indicating that the catalyst has excellent stability.

[0092] Example 4

[0093] Synthesis, structure and catalytic performance of Co / CoO / B2O3 / Ti catalysts

[0094] Catalyst preparation:

[0095] In this embodiment, the only difference between the cobalt foam (CF) and the Ti mesh is that the other preparation conditions are the same as in Example 1.

[0096] Electrocatalytic performance testing of catalysts:

[0097] Results of hydrogen evolution reaction polarization curve test ( Figure 18 Figure a) shows that the Co / CoO / B2O3 / Ti catalyst exhibits excellent electrocatalytic activity for the hydrogen evolution reaction, requiring only 58 mV of hydrogen evolution overpotential to reach 10 mA / cm² in 1.0 M potassium hydroxide alkaline solution. 2 Current density; 10-hour constant current durability test results ( Figure 18 Figure b) shows that the catalyst activity did not show a significant decline, indicating that the catalyst has excellent stability.

[0098] Example 5

[0099] Synthesis, structure and catalytic performance of Ni / NiO / B2O3 / NF catalysts

[0100] Catalyst preparation:

[0101] In this embodiment, the only difference between the synthesis method is that CoSO4·7H2O is replaced with NiSO4·7H2O, while the other preparation conditions are the same as in Example 1.

[0102] Electrocatalytic performance testing of catalysts:

[0103] The results of the hydrogen evolution reaction polarization curve test Figure 19 a) show that the Ni / NiO / B2O3 / NF catalyst has excellent electrocatalytic activity for the hydrogen evolution reaction, and only requires a hydrogen evolution overpotential of 19 mV to achieve a current density of 10 mA / cm 2 2 in 1.0 M potassium hydroxide solution; the results of the 10-hour constant current durability test Figure 19 b) show that the activity of the catalyst has not decreased significantly, indicating that the catalyst has excellent stability.

[0104] Example 6

[0105] Synthesis, structure and catalytic performance of Ni-Co / NiO / CoO / B2O3 / NF catalyst

[0106] Catalyst preparation:

[0107] In the synthesis method of this example, similar to Example 1, the only difference is that the CoSO4·7H2O (0.12 M) solution is replaced by a mixed solution of NiSO4·7H2O (0.06 M) and CoSO4·7H2O (0.06 M).

[0108] Electrocatalytic performance test of the catalyst:

[0109] The results of the hydrogen evolution reaction polarization curve test Figure 20 a) show that the Ni-Co / NiO / CoO / B2O3 / NF catalyst has excellent electrocatalytic activity for the hydrogen evolution reaction, and only requires a hydrogen evolution overpotential of 11 mV to achieve a current density of 10 mA / cm 2 2 in 1.0 M potassium hydroxide solution; the results of the 10-hour constant current durability test Figure 20 b) show that the activity of the catalyst has not decreased significantly, indicating that the catalyst has excellent stability.

[0110] The above examples are preferred embodiments of the present application, but the embodiments of the present application are not limited by the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present application are equivalent replacement methods and are included in the protection scope of the present application.

Claims

1. A high-activity boronate-mediated alkaline hydrogen evolution electrocatalyst, characterized in that: The electrocatalyst is composed of a metal active phase, a metal oxide active phase, a boron oxide base phase and a carrier, the metal active phase is dispersed on the surface of the metal oxide active phase and the boron oxide base phase, the metal oxide active phase and the boron oxide base phase are mixedly distributed and are both loaded on the carrier; the metal active phase is a transition metal, the metal oxide active phase is a transition metal oxide; the carrier is selected from a foam metal, a metal mesh, an ion exchange resin, a molecular sieve or a porous carbon material; the preparation of the high-activity basic hydrogen evolution electrocatalyst comprises the following steps: (1) adding a carrier material into an aqueous solution containing a transition group metal salt, a boron-containing reducing agent and a complexing agent, growing a metal boride derivative precursor with nanostructure on the surface of the carrier material through a reduction reaction; the transition group metal salt refers to at least one of halide, nitrate, sulfate, sulfamate or acetate of a transition group metal; the transition group metal refers to at least one of Fe, Co and Ni; the boron-containing reducing agent is C2H 10 BN; the ratio of the total amount of the transition group metal salt to the amount of substance of the boron-containing reducing agent is 9:4-36; the ratio of the total amount of the transition group metal salt to the amount of substance of the complexing agent is 9:4-36; (2) washing and drying the metal boride derivative precursor obtained in step (1), and then performing high-temperature heat treatment in an inert atmosphere to obtain the high-activity basic hydrogen evolution electrocatalyst with boride as a medium.

2. The boride-mediated highly active basic hydrogen evolution electrocatalyst according to claim 1, characterized in that: The metal active phase exists in the form of nanoparticles, and the particle size is 1-10 nm.

3. The boride-mediated highly active basic hydrogen evolution electrocatalyst of claim 1, wherein: The metal oxide active phase and the boron oxide base phase exist in the form of amorphous; the metal oxide active phase and the boron oxide base phase have a nanoporous sheet structure, the nanopore size is 2-10 nm, the nanosheet thickness is 1-10 nm, and the nanosheet length is 50-500000 nm.

4. The method for preparing a high-activity boride-mediated basic hydrogen evolution electrocatalyst according to any one of claims 1 to 3, characterized in that, comprising the following preparation steps: (1) adding a carrier material into an aqueous solution containing a transition group metal salt, a boron-containing reducing agent and a complexing agent, growing a metal boride derivative precursor with nanostructure on the surface of the carrier material through a reduction reaction; the transition group metal salt refers to at least one of halide, nitrate, sulfate, sulfamate or acetate of a transition group metal; the transition group metal refers to at least one of Fe, Co and Ni; the boron-containing reducing agent is C2H 10 BN; the ratio of the total amount of the transition group metal salt to the amount of substance of the boron-containing reducing agent is 9:4-36; the ratio of the total amount of the transition group metal salt to the amount of substance of the complexing agent is 9:4-36; (2) washing and drying the metal boride derivative precursor obtained in step (1), and then performing high-temperature heat treatment in an inert atmosphere to obtain the high-activity basic hydrogen evolution electrocatalyst with boride as a medium.

5. The method for preparing a high-activity boron-hydride-mediated alkaline hydrogen evolution electrocatalyst according to claim 4, characterized in that: In step (1), the complexing agent is C4H4Na2O4.

6. The method for preparing a highly active alkaline hydrogen evolution electrocatalyst mediated by boride according to claim 4, characterized in that: In the aqueous solution in step (1), the total concentration of the transition metal salt is 0.001-1 M, the concentration of the boron-containing reducing agent is 0.001-1 M, and the concentration of the complexing agent is 0.001-1 M; the temperature of the reduction reaction is 25-90°C; and the time of the reduction reaction is 5-200 min.

7. The method for preparing a highly active alkaline hydrogen evolution electrocatalyst mediated by boride according to claim 4, characterized in that: In step (2), the inert atmosphere is argon; the temperature of the high-temperature heat treatment is 100-500°C; and the time of the high-temperature heat treatment is 1-5 h.

8. Use of the high-activity basic hydrogen evolution electrocatalyst with boride as a medium according to any one of claims 1-3 in the electrolytic water decomposition for hydrogen production.

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