A method for hydrogen production based on the coupling of WS2 / Pt composite catalysts to prepare azofuran energetic materials

Abstract

This invention discloses a hydrogen production method based on the coupling of a WS2 / Pt composite catalyst to prepare azofuran energetic materials, comprising the following steps: placing a CC@Pt / WS2 electrode in a soda ash solution and a copper oxide nanowire electrode in an alkaline solution containing aminofuran; forming an H-type electrolysis system separated by an anion exchange membrane, with the CC@Pt / WS2 electrode as the cathode and the copper oxide nanowire electrode as the anode; and achieving hydrogen production at the cathode and synthesis of 3,3'-diamino-4,4'-azofuran energetic materials at the anode based on the H-type electrolysis system. This invention replaces the traditional oxygen evolution reaction with an electrochemical oxidation synthesis of 3,3'-diamino-4,4'-azofuran energetic materials with a lower oxidation potential, and couples this with water electrolysis for hydrogen production, enabling low-energy hydrogen production and green synthesis of azofuran energetic materials.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen energy and energetic materials technology, and specifically relates to a method for preparing azofuran energetic materials based on the coupling of WS2 / Pt composite catalysts. Background Technology

[0002] Hydrogen energy has attracted widespread attention due to its clean and pollution-free nature, high calorific value, and recyclability. Existing traditional hydrogen production processes mainly include hydrogen production from fossil fuels, hydrogen production from water electrolysis, hydrogen production from photocatalytic water splitting, and hydrogen production from microorganisms.

[0003] Among the aforementioned existing technologies, water electrolysis for hydrogen production is a clean method, but there are still some factors that restrict its development. Among them, the slow oxygen evolution reaction (OER) rate is an important factor affecting the efficiency of electrocatalytic water splitting for hydrogen production (HER). Selecting an oxidation reaction with a lower potential and higher added value to replace OER and form a coupling system with HER, while designing an efficient HER catalyst, can fundamentally solve the problems of excessively high voltage and high energy consumption in hydrogen production cells.

[0004] Energetic materials are compounds or mixtures containing explosive groups or oxidizers and combustibles that can independently undergo chemical reactions and output energy. They are an important component of military explosives, propellants, and rocket propellant formulations. Among them, nitrogen-rich heterocyclic compounds are considered promising energetic compounds because they can simultaneously meet multiple requirements in the challenging field of energetic materials. Conventional organic synthesis methods usually involve organic reagents and oxidizers, which typically have drawbacks such as toxicity, corrosiveness, high cost, and difficulty in removing byproducts. Furthermore, the reactions must be carried out at high temperatures, posing significant safety hazards.

[0005] In summary, there is an urgent need for a new method that can couple the preparation of azofuran energetic materials with hydrogen production. Summary of the Invention

[0006] The purpose of this invention is to provide a hydrogen production method based on the coupling of a WS2 / Pt composite catalyst to prepare azofuran energetic materials, thereby solving one or more of the aforementioned technical problems. In the technical solution provided by this invention, the electrochemical oxidation synthesis of 3,3'-diamino-4,4'-azofuran energetic materials with a lower oxidation potential replaces the traditional oxygen evolution reaction, and is coupled with water electrolysis for hydrogen production, enabling low-energy hydrogen production and green synthesis of azofuran energetic materials.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides a method for preparing azofuran energetic materials based on the coupling of WS2 / Pt composite catalysts, comprising the following steps:

[0009] The CC@Pt / WS2 electrode was placed in a soda ash solution, and the copper oxide nanowire electrode was placed in an alkaline solution containing aminofuran; with the CC@Pt / WS2 electrode as the cathode and the copper oxide nanowire electrode as the anode, an H-type electrolysis system separated by an anion exchange membrane was formed.

[0010] Based on the H-type electrolysis system, hydrogen production at the cathode and the synthesis of 3,3'-diamino-4,4'-azofuran energetic materials at the anode are achieved.

[0011] A further improvement of the present invention lies in the step of realizing hydrogen production at the cathode and synthesis of the 3,3'-diamino-4,4'-azofuran energetic material at the anode based on the H-type electrolysis system.

[0012] The cathode undergoes an alkaline HER process on the surface of the CC@WS2 / Pt catalyst; the anode undergoes an azotization reaction on the surface of the copper oxide nanowire catalyst.

[0013] A further improvement of the present invention is that the method for preparing the CC@Pt / WS2 electrode includes the following steps:

[0014] The pre-obtained mixed aqueous solution of sodium tungstate and thioacetamide was adjusted to a weakly acidic state to obtain the adjusted mixed aqueous solution.

[0015] Conductive carbon cloth, a carrier, is added to the adjusted mixed aqueous solution to carry out a hydrothermal reaction, thereby obtaining CC@WS2;

[0016] CC@WS2 was cleaned, dried, and Pt nanoparticles were deposited to obtain a CC@WS2 / Pt electrode.

[0017] A further improvement of the present invention is that, in the pre-obtained aqueous solution of sodium tungstate and thioacetamide, the molar ratio of sodium tungstate to thioacetamide is 1:(5.4-6.2).

[0018] A further improvement of the present invention is that the carbon cloth is a carbon cloth cleaned with acetone and ethanol, and the carbon cloth area is 2 cm². 2 ~6cm 2 .

[0019] A further improvement of the present invention is that the hydrothermal reaction temperature is 180℃~220℃ and the reaction time is 12h~24h.

[0020] A further improvement of the present invention is that the step of depositing Pt nanoparticles includes:

[0021] Based on Pt ion electrolyte, Pt deposition reaction was carried out in a three-electrode system by cyclic voltammetry, and Pt nanoparticles were deposited on cleaned and dried CC@WS2.

[0022] A further improvement of the present invention is that, in the step of performing the Pt deposition reaction by cyclic voltammetry in a three-electrode system,

[0023] The cyclic voltammetry test voltage range is -0.5 to 0 V vs. RHE, the number of cyclic voltammetry test cycles is 200 to 400, and the cyclic voltammetry scan rate is 50 to 100 mV / s.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The hydrogen production method provided by this invention replaces the traditional oxygen evolution reaction with an electrochemical oxidation reaction to synthesize 3,3'-diamino-4,4'-azofuran energetic material, which has a lower oxidation potential. This reaction is coupled with water electrolysis for hydrogen production, enabling low-energy hydrogen production and green synthesis of azofuran energetic material. The electrochemical oxidation reaction to synthesize 3,3'-diamino-4,4'-azofuran energetic material can be carried out at room temperature, avoiding the use of oxidizing agents and cumbersome byproduct separation steps. Ultimately, this achieves green electrochemical synthesis of 3,3'-diamino-4,4'-azofuran energetic material. Furthermore, hydrogen can be produced by applying a relatively low cell voltage under the drive of a WS2 / Pt composite catalyst. In summary, the coupled preparation method disclosed in this invention achieves low-cell-pressure, low-energy hydrogen production while simultaneously realizing the green electrosynthesis of 3,3'-diamino-4,4'-azofuran energetic material, achieving two goals at once. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below; obviously, the drawings described below are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a method for preparing azofuran energetic materials based on the coupling of WS2 / Pt cathode catalyst and copper oxide nanowire anode catalyst provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the preparation of 3,3'-diamino-4,4'-azofuran energetic materials using conventional organic synthesis methods in the comparative example of this invention;

[0029] Figure 3 This is a schematic diagram of the scanning electron microscope characterization results of the conductive carbon cloth (CC) supported WS2 / Pt catalyst (CC@WS2 / Pt) in Example 1 of the present invention;

[0030] Figure 4This is a schematic diagram of the HAADF-STEM transmission electron microscopy characterization results of WS2 / Pt in Embodiment 1 of the present invention;

[0031] Figure 5 This is a schematic diagram of the element mapping results of WS2 / Pt in Embodiment 1 of the present invention; wherein, Figure 5 (a) is the STEM image of WS2 / Pt. Figure 5 (b) is the Pt element mapping diagram. Figure 5 (c) is the mapping diagram of element W. Figure 5 (d) is the mapping diagram of element S;

[0032] Figure 6 This is a schematic diagram of the scanning electron microscope characterization results of copper oxide nanowires in Example 1 of the present invention; wherein, Figure 6 (a) is a scanning electron microscope image of copper oxide nanowires at low magnification. Figure 6 (b) is a scanning electron microscope image of copper oxide nanowires at high magnification;

[0033] Figure 7 This is an X-ray diffraction pattern of CC@WS2, CC@WS2 / Pt, and copper oxide nanowires in Embodiment 1 of the present invention; wherein, Figure 7 (a) shows the X-ray diffraction patterns of CC@WS2 and CC@WS2 / Pt. Figure 7 (b) is the X-ray diffraction pattern of the anolyte copper oxide nanowire catalyst;

[0034] Figure 8 These are the LSV and Tafel curves of alkaline HER for CC@WS2, CC@WS2 / Pt, and commercial Pt / C in Embodiment 1 of the present invention; wherein, Figure 8 (a) shows the LSV curves of alkaline HER for CC@WS2, CC@WS2 / Pt, and commercial Pt / C. Figure 8 (b) shows the Tafel curves of CC@WS2, CC@WS2 / Pt, and commercial Pt / C.

[0035] Figure 9 These are physical images and LSV curves of the coupling system between basic HER and the electrosynthesized 3,3'-diamino-4,4'-azofuran energetic material in Example 1 of this invention; wherein, Figure 9 Image (a) is a schematic diagram of the LSV curve of the two-electrode coupling system. Figure 9 (b) is a physical schematic diagram of the coupled system;

[0036] Figure 10 The nuclear magnetic resonance imaging (NMR) of the electrosynthesized 3,3'-diamino-4,4'-azofuran energetic material in Example 1 of this invention is shown in Figure 1.13 C-spectrum and differential scanning calorimetry curve; among which... Figure 10 (a) represents the nuclear magnetic resonance (NMR) of 3,3'-diamino-4,4'-azofuran energetic material. 13 C spectrum, Figure 10 (b) is a schematic diagram of the differential scanning calorimetry curve obtained by differential scanning calorimetry testing of the obtained 3,3'-diamino-4,4'-azofuran energetic material. Detailed Implementation

[0037] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0038] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0039] It should be noted that the process equipment or apparatus not specifically mentioned in the following embodiments are all conventional equipment or apparatus in the art.

[0040] Furthermore, it should be understood that the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, does not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps, unless otherwise stated. It should also be understood that the combined connection relationship between one or more devices / apparatus mentioned in this invention does not preclude the existence of other devices / apparatus before or after the combined devices / apparatus, or the insertion of other devices / apparatus between these explicitly mentioned devices / apparatus, unless otherwise stated. Moreover, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or limiting the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0041] Please see Figure 1 The present invention provides a method for preparing azofuran energetic materials based on the coupling of WS2 / Pt composite catalysts, which specifically includes the following steps:

[0042] The CC@Pt / WS2 electrode was placed in a soda ash solution, and the copper oxide nanowire electrode was placed in an alkaline solution containing aminofuran to form an H-type electrolysis system separated by an anion exchange membrane.

[0043] Based on the H-type electrolysis system, hydrogen production and the synthesis of 3,3'-diamino-4,4'-azofuran energetic materials are achieved.

[0044] In this embodiment of the invention, the specific steps for achieving hydrogen production and synthesis of 3,3'-diamino-4,4'-azofuran energetic materials based on the H-type electrolysis system include:

[0045] Step 1: Prepare a copper oxide nanowire catalyst electrode supported on a copper foam substrate;

[0046] Step 2: Prepare CC@WS2 / Pt hydrogen production catalyst electrode;

[0047] Step 3: The prepared copper oxide nanowire catalyst electrode and CC@WS2 / Pt hydrogen production catalyst electrode are used as the anode and cathode of the coupling system, respectively, and immersed in their respective electrolytes for dual-electrode coupling test.

[0048] Step 4: Characterize and analyze the anolyte product to determine that the product structure is a pure-phase 3,3'-diamino-4,4'-azofuran energetic material.

[0049] In the preparation method of the above embodiments of the present invention, the alkaline HER process occurring on the surface of the CC@WS2 / Pt catalyst at the cathode is as follows:

[0050] H2O(l)+e – →H*+OH – (Volmer);

[0051] H* + H₂O(l) + e – →H2+OH – (Heyrovsky);

[0052] The azotization reaction that occurs on the surface of the copper oxide nanowire catalyst at the anode is as follows: In this embodiment of the invention, the preparation method of copper oxide nanowire electrode includes: soaking copper foam in an alkaline solution containing an oxidant for a period of time to generate copper hydroxide nanowires, and then obtaining pure phase copper oxide nanowires by high-temperature calcination in air; wherein the oxidant is one of sodium persulfate and ammonium persulfate, the soaking time can be 30-60 min, the calcination temperature is 200-400℃, and the calcination time is 2-4 hours.

[0053] In this embodiment of the invention, the method for preparing the CC@Pt / WS2 electrode includes the following steps:

[0054] Step 1: Add oxalic acid to the mixed aqueous solution of sodium tungstate and thioacetamide (TAA) to adjust the pH to make the solution weakly acidic, and obtain the adjusted mixed aqueous solution.

[0055] Step 2: Add the cleaned conductive carrier carbon cloth (CC) to the adjusted mixed aqueous solution obtained in Step 1 and carry out a hydrothermal reaction to obtain CC-loaded WS2 nanosheets (CC@WS2);

[0056] Step 3: The reacted CC@WS2 system is rinsed with water and ethanol and dried for subsequent deposition of Pt nanoparticles.

[0057] Step four: Different masses of chloroplatinic acid were added to a 1.0M KOH solution to prepare a Pt ion electrolyte; then, a Pt deposition reaction was carried out in a three-electrode system using cyclic voltammetry to prepare a CC@WS2 / Pt electrode.

[0058] In step one of this embodiment of the invention, the molar ratio of sodium tungstate to TAA is 1:(5.4-6.2), and the molar amount of oxalic acid is (6.2-7.2) mmol; pure phase WS2 nanosheets can be prepared within this range of sodium tungstate to TAA ratio and oxalic acid amount.

[0059] In step two of this embodiment of the invention, the carbon cloth is cleaned with acetone and ethanol during the cleaning process, and the area of ​​the carbon cloth is 2 cm². 2 ~6cm 2 The hydrothermal reaction temperature is 180℃~220℃; the hydrothermal reaction time in step two is 12h~24h; within this temperature and time range, the reaction can effectively regulate the nucleation and growth of WS2 on the CC surface.

[0060] In step three of this embodiment of the invention, the temperature range during drying is 30℃~60℃, and the drying time is 0.5h~2h.

[0061] In step four of this embodiment, the chloroplatinic acid content in the electrolyte is 10 mg to 30 mg. By controlling the amount of chloroplatinic acid, the loading of Pt nanoparticles can be controlled, and the catalytic activity is better within this chloroplatinic acid content range. The electrodes are CC@WS2 (working electrode), graphite rod (counter electrode), and Hg / HgO (reference electrode). The cyclic voltammetry test voltage range is -0.5 to 0 V vs. RHE, which is the activity range of electrodeposited Pt nanoparticles. The number of cyclic voltammetry test cycles is 200 to 400. Outside this test range, the optimal alkaline HER activity cannot be achieved due to insufficient or excessive amount of electrodeposited Pt. The cyclic voltammetry scan rate in step four is 50 to 100 mV / s.

[0062] Please see Figure 2 , Figure 2The existing conventional preparation method is shown. This conventional method requires high temperature (~70°C) and strong oxidizing agent sodium persulfate / ammonium persulfate, which greatly increases the safety risks in the preparation process and the generated byproduct metal salts cause waste of raw materials.

[0063] Compared with the existing traditional preparation methods, the preparation scheme provided by the present invention avoids the defects of traditional organic preparation methods. It uses green electrons as an oxidant at the anode to prepare 3,3'-diamino-4,4'-azofuran energetic materials, and there is no need to separate the by-products generated by the oxidant. The reaction can be carried out at room temperature. At the same time, since this oxidation reaction has a lower reaction point (0.2~0.5V vs RHE) compared to OER (1.23V vs RHE), the cathode hydrogen production tank pressure and energy consumption of the coupled system are lower, achieving a double benefit.

[0064] To further explain, in the design of the cathode HER catalyst disclosed in this embodiment of the invention, the addition of Pt nanoparticles can activate the relatively inert WS2 basal surface, generating more S-side active sites, thereby promoting the adsorption of HER intermediates and thus promoting HER activity. For the anode, since the azotization reaction has a lower oxidation potential (0.2-0.5V vs RHE) compared to conventional OER (1.23V vs. RHE), using the electro-oxidative azotization reaction to replace OER and couple it with HER can achieve electrochemical water splitting to produce hydrogen under lower cell voltage and lower energy consumption conditions, reducing the cost of water electrolysis to produce hydrogen. At the same time, it realizes a safe, mild, and green electrosynthetic azofuran energetic material without the need for toxic and harmful strong oxidants.

[0065] In summary, existing coupling technologies, including those using oxidation reactions of methanol, ethanol, urea, furfural, etc., to replace OER and construct coupling systems with HER, exhibit lower cell voltage and reduced energy consumption than traditional water electrolysis. However, no technical solution for coupling and preparing energetic materials has been found. In view of this, this invention discloses for the first time a new coupling system, namely, the green electro-oxidation reaction to prepare azofuran energetic material and coupling it with HER, achieving low cell voltage and low energy consumption hydrogen production while simultaneously carrying out green electrosynthesis of azofuran energetic material at room temperature. The low cell voltage obtained by the coupling system in this invention is comparable to that of existing hydrogen production coupling systems using oxidation reactions of urea, furfural, etc.

[0066] Example 1

[0067] This invention provides a method for preparing low-energy hydrogen production and green synthesis of azofuran energetic materials based on a Pt / WS2 composite catalyst, comprising the following steps:

[0068] Step 1: Add 6.2 mmol of oxalic acid to a mixed aqueous solution of sodium tungstate and thioacetamide (TAA) in a molar ratio of 1:5.8 to make the solution weakly acidic;

[0069] Step 2: Transfer to a container filled with treated conductive carrier carbon cloth (CC, 3cm) 2 The polytetrafluoroethylene liner was placed inside a stainless steel hydrothermal reactor and subjected to a hydrothermal reaction at 200°C for 24 hours.

[0070] Step 3: The reacted CC-loaded WS2 nanosheets (CC@WS2) system was rinsed with water and ethanol and dried in an oven at 60°C for 1 hour;

[0071] Step 4: Add 20 mg of chloroplatinic acid to 30 mL of 1.0 M KOH solution to prepare Pt ion electrolyte. Then, Pt deposition reaction was carried out by cyclic voltammetry in a three-electrode system of CC@WS2 (working electrode), graphite rod (counter electrode), and Hg / HgO (reference electrode) at a scan rate of 50 mV / s and 400 scans, finally obtaining the CC@WS2 / Pt electrode;

[0072] Step 5: Soak commercial copper foam in dilute hydrochloric acid for 30 minutes to remove surface oxides. Then, immerse the treated copper foam in a solution of 0.1M (NH4)2S2O8 and 2.6M NaOH for 30 minutes to obtain copper hydroxide nanowires. Remove the copper hydroxide nanowires, wash them with water, and dry them in an oven at 60℃ for 12 hours. Finally, calcine the copper hydroxide nanowires in air at 300℃ for 2 hours to obtain copper oxide nanowire electrodes.

[0073] Step six: Place the CC@Pt / WS2 electrode in a soda ash solution and place the copper oxide nanowire electrode in an alkaline solution containing aminofurazan to form an H-type electrolysis system separated by anion exchange membrane; based on the H-type electrolysis system, realize hydrogen production and the synthesis of 3,3'-diamino-4,4'-azofurazan energetic materials.

[0074] based on Figure 2 It is known that existing traditional organic synthesis methods usually involve organic reagents and oxidants. These reagents are often toxic, corrosive, costly, and have drawbacks such as difficulty in removing byproducts. Furthermore, the reactions must be carried out at high temperatures, which poses significant safety risks.

[0075] Please see Figure 1Taking the preparation method disclosed in Example 1 as an example, this invention addresses the shortcomings of traditional azo-based organic energetic materials synthesis processes by developing a green and mild electrochemical method for synthesizing azo-based energetic materials. The reaction can be carried out at room temperature and avoids the use of oxidizing agents and cumbersome byproduct separation steps, ultimately achieving green electrochemical synthesis of energetic materials. Furthermore, since the electro-oxidative synthesis of 3,3'-diamino-4,4'-azofuran energetic materials has a lower oxidation potential (0.2–0.5 V vs RHE) compared to OER (1.23 V vs RHE), the coupling system of HER and electro-oxidative synthesis of 3,3'-diamino-4,4'-azofuran energetic materials exhibits lower hydrogen production cell voltage and hydrogen production energy consumption. The hydrogen production electrode (cathode) and the preparation of 3,3'-diamino-4,4'-azofuran energetic materials (anode) used are CC@WS2 / Pt and copper oxide nanowire electrodes, respectively.

[0076] Please see Figure 3 The figure shows the uniform growth of WS2 nanosheets, with no obvious loading of Pt nanoparticles. This preliminarily indicates that the Pt particle size is small, which also shows the uniformity of Pt loading and that no agglomeration has occurred.

[0077] Please see Figure 4 The lens image clearly shows that the bright spots of Pt nanoparticles are uniformly loaded on the surface of WS2 nanosheets, which demonstrates the successful preparation of the cathode hydrogen production catalyst of the present invention.

[0078] Please see Figure 5 The presence of Pt elements uniformly distributed on the surface of WS2 nanosheets further indicates that Pt nanoparticles are uniformly loaded on the WS2 surface; at the same time, it also shows that W and S elements are uniformly distributed on the surface of the nanosheets.

[0079] Please see Figure 6 These are scanning electron microscope images of copper oxide nanowires at different magnifications. Figure 6 (a) is a scanning electron microscope image of copper oxide nanowires at low magnification, showing that large areas of nanowire-shaped copper oxide are uniformly grown on the surface of copper foam. Figure 6 Image (b) is a high-magnification scanning electron microscope image of copper oxide nanowires, showing that the copper oxide nanowires interlock to form a three-dimensional nanowire structure.

[0080] Please see Figure 7 , Figure 7(a) shows the X-ray diffraction patterns of CC@WS2 and CC@WS2 / Pt. The diffraction peaks of CC@WS2 are consistent with the standard card (JCPDS no. 08-0237) of 2H-WS2, indicating that WS2 is a pure phase material without other impurities. The broad peaks at 21° and 57° are signals from the CC conductive carbon substrate. In addition to the characteristic peaks of WS2, CC@WS2 / Pt loaded with Pt nanoparticles shows new diffraction peaks at 40° and 46°, which are characteristic peaks of Pt metal (JCPDS no. 04-0802). This indicates that Pt is loaded on the WS2 surface in a metallic state rather than an oxidized state, proving that the Pt nanoparticles are pure phase and there are no other Pt oxides. Figure 7 (b) shows the X-ray diffraction pattern of the anolyte copper oxide nanowire catalyst. The peaks at 43°, 50°, and 74° correspond to the signals of the copper foam substrate. The diffraction peaks at 35°, 39°, and 48° correspond to chalcopyrite-type copper oxide (JCPDS no. 45-0937); the diffraction peaks at 36°, 42°, and 61° correspond to cubic copper oxide (JCPDS no. 78-0428), indicating that the copper oxide nanowires prepared on the copper foam substrate have both of these copper oxide crystal forms.

[0081] Please see Figure 8 , Figure 8 (a) shows the LSV curves for alkaline HER using CC@WS2, CC@WS2 / Pt, and commercial Pt / C. A lower overpotential indicates higher HER catalytic activity. (At 10 mA / cm²) 2 At the specified current density, the overpotential of CC@WS2 / Pt is only 27.1 mV. This activity is lower than that of commercial Pt / C catalysts (30 mV) and significantly lower than that of CC@WS2 (315 mV). Specifically, at 100 mA / cm², the overpotential is... 2 At the specified current density, the overpotential of CC@WS2 / Pt is only 60.4 mV, far lower than that of commercial Pt / C catalysts (81.9 mV). This result indicates that loading Pt nanoparticles onto the WS2 surface significantly enhances the HER catalytic activity, and is comparable to, or even surpasses, that of commercial Pt / C catalysts at high current densities. Figure 8Table (b) shows the Tafel curves for CC@WS2, CC@WS2 / Pt, and commercial Pt / C. A lower Tafel slope indicates a faster reaction kinetic rate. Based on this, the fitted Tafel slope for CC@WS2 / Pt is 30.2 mV / dec, similar to the Pt / C catalyst (28.0 mV / dec) and significantly lower than that of CC@WS2 (321.9 mV / dec). These results indicate that the reaction kinetic rate of CC@WS2 / Pt is close to that of the Pt / C catalyst, demonstrating that the CC@WS2 / Pt catalyst prepared in this invention exhibits excellent HER hydrogen production performance in the following coupling system.

[0082] Please see Figure 9 , Figure 9 (a) shows the LSV curves of the two-electrode coupled system. The anode and cathode are copper oxide nanowires supported on copper foam and CC@WS2 / Pt, respectively; the electrolytes at the anode and cathode are 1.0 M KOH + 3,4-diaminofuran and 1.0 M KOH, respectively, and the anode and cathode electrolytes are separated by anion exchange membranes. At 10 mA / cm²... 2 Under current conditions, the cell voltage for conventional water electrolysis to produce hydrogen is 1.70V. After preparing 3,3'-diamino-4,4'-azofuran energetic material via electro-oxidative azotization of 3,4-diaminofuran to replace the OER and constructing a coupling system with the HER, the cell voltage was reduced to 1.29V, a decrease of 410mV compared to conventional water electrolysis for hydrogen production. This demonstrates a significant reduction in cell voltage and energy consumption. Figure 9 Image (b) shows the physical diagram of the coupled system. LSV testing revealed a darkening of the anolyte color, preliminarily indicating an azotization reaction under the influence of the electric field. Hydrogen gas was clearly observed escaping from the cathode CC@WS2 / Pt surface, demonstrating the successful establishment of the coupled co-production system in this invention.

[0083] Please see Figure 10 , Figure 10 (a) represents the nuclear magnetic resonance (NMR) of 3,3'-diamino-4,4'-azofuran energetic material. 13 C-spectrum, after the coupled system was tested, the anolyte was washed with boiling water and dried by rotary evaporation to obtain a yellow product, which was then subjected to... 13 C10 NMR characterization. The -C-NH2 and -CN=N- bonds of the 3,3'-diamino-4,4'-azofuran structure were found at 151.1 ppm and 156.2 ppm, respectively, demonstrating the successful synthesis of 3,3'-diamino-4,4'-azofuran energetic materials via a green electrochemical method. Figure 10 Image (b) shows the differential scanning calorimetry (DSC) analysis of the obtained 3,3'-diamino-4,4'-azofuran energetic material. Only one distinct exothermic peak was observed at 327.1 °C.13 The 1 / 2C NMR results confirm the successful preparation of a pure-phase 3,3'-diamino-4,4'-azofuran energetic material. This verifies that the coupling system disclosed in this invention possesses a dual-functionality, enabling both low-energy hydrogen production and green synthesis of 3,3'-diamino-4,4'-azofuran energetic material.

[0084] Example 2

[0085] This invention provides a method for preparing azofuran energetic materials based on the coupling of a WS2 / Pt composite catalyst, comprising the following steps:

[0086] The CC@Pt / WS2 electrode was placed in a soda ash solution, and the copper oxide nanowire electrode was placed in an alkaline solution containing aminofuran; with the CC@Pt / WS2 electrode as the cathode and the copper oxide nanowire electrode as the anode, an H-type electrolysis system separated by an anion exchange membrane was formed.

[0087] Based on the H-type electrolysis system, hydrogen production at the cathode and the synthesis of 3,3'-diamino-4,4'-azofuran energetic materials at the anode are realized; wherein, the cathode undergoes an alkaline HER process on the surface of CC@WS2 / Pt catalyst; and the anode undergoes an azotization reaction on the surface of copper oxide nanowire catalyst.

[0088] In this embodiment of the invention, the method for preparing the CC@Pt / WS2 electrode includes the following steps:

[0089] The pre-prepared aqueous solution of sodium tungstate and thioacetamide was adjusted to a weakly acidic state to obtain the adjusted aqueous solution; wherein the molar ratio of sodium tungstate to thioacetamide was 1:5.4.

[0090] Conductive carbon cloth was added to the adjusted mixed aqueous solution, and a hydrothermal reaction was carried out to obtain CC@WS2; wherein the carbon cloth was carbon cloth cleaned with acetone and ethanol, and the carbon cloth area was 2 cm². 2 The hydrothermal reaction temperature is 180℃, and the reaction time is 12 hours.

[0091] CC@WS2 was cleaned, dried, and Pt nanoparticles were deposited to obtain a CC@WS2 / Pt electrode. The Pt nanoparticle deposition step included: Pt deposition reaction was carried out in a three-electrode system based on Pt ion electrolyte using cyclic voltammetry, and Pt nanoparticles were deposited on the cleaned and dried CC@WS2. The cyclic voltammetry test voltage range was -0.5 to 0 V vs. RHE, the number of cyclic voltammetry tests was 200, and the cyclic voltammetry scan rate was 50 mV / s.

[0092] Example 3

[0093] This invention provides a method for preparing azofuran energetic materials based on the coupling of a WS2 / Pt composite catalyst, comprising the following steps:

[0094] The CC@Pt / WS2 electrode was placed in a soda ash solution, and the copper oxide nanowire electrode was placed in an alkaline solution containing aminofuran; with the CC@Pt / WS2 electrode as the cathode and the copper oxide nanowire electrode as the anode, an H-type electrolysis system separated by an anion exchange membrane was formed.

[0095] Based on the H-type electrolysis system, hydrogen production at the cathode and the synthesis of 3,3'-diamino-4,4'-azofuran energetic materials at the anode are realized; wherein, the cathode undergoes an alkaline HER process on the surface of CC@WS2 / Pt catalyst; and the anode undergoes an azotization reaction on the surface of copper oxide nanowire catalyst.

[0096] In this embodiment of the invention, the method for preparing the CC@Pt / WS2 electrode includes the following steps:

[0097] The pre-prepared aqueous solution of sodium tungstate and thioacetamide was adjusted to a weakly acidic state to obtain the adjusted aqueous solution; wherein the molar ratio of sodium tungstate to thioacetamide was 1:6.2.

[0098] Conductive carbon cloth was added to the adjusted mixed aqueous solution, and a hydrothermal reaction was carried out to obtain CC@WS2; wherein the carbon cloth was carbon cloth cleaned with acetone and ethanol, and the carbon cloth area was 6 cm². 2 The hydrothermal reaction temperature is 220℃, and the reaction time is 24 hours.

[0099] CC@WS2 was cleaned, dried, and Pt nanoparticles were deposited to obtain a CC@WS2 / Pt electrode. The Pt nanoparticle deposition step included: Pt deposition reaction was carried out in a three-electrode system based on Pt ion electrolyte using cyclic voltammetry, and Pt nanoparticles were deposited on the cleaned and dried CC@WS2. The cyclic voltammetry test voltage range was -0.5 to 0 V vs. RHE, the number of cyclic voltammetry tests was 400, and the cyclic voltammetry scan rate was 100 mV / s.

[0100] Example 4

[0101] This invention provides a method for preparing azofuran energetic materials based on the coupling of a WS2 / Pt composite catalyst, comprising the following steps:

[0102] The CC@Pt / WS2 electrode was placed in a soda ash solution, and the copper oxide nanowire electrode was placed in an alkaline solution containing aminofuran; with the CC@Pt / WS2 electrode as the cathode and the copper oxide nanowire electrode as the anode, an H-type electrolysis system separated by an anion exchange membrane was formed.

[0103] Based on the H-type electrolysis system, hydrogen production at the cathode and the synthesis of 3,3'-diamino-4,4'-azofuran energetic materials at the anode are realized; wherein, the cathode undergoes an alkaline HER process on the surface of CC@WS2 / Pt catalyst; and the anode undergoes an azotization reaction on the surface of copper oxide nanowire catalyst.

[0104] In this embodiment of the invention, the method for preparing the CC@Pt / WS2 electrode includes the following steps:

[0105] The pre-obtained aqueous solution of sodium tungstate and thioacetamide was adjusted to a weakly acidic state to obtain the adjusted aqueous solution; wherein the molar ratio of sodium tungstate to thioacetamide was 1:6.

[0106] Conductive carbon cloth was added to the adjusted mixed aqueous solution, and a hydrothermal reaction was carried out to obtain CC@WS2; wherein the carbon cloth was carbon cloth cleaned with acetone and ethanol, and the carbon cloth area was 4 cm². 2 The hydrothermal reaction temperature is 200℃, and the reaction time is 20h.

[0107] CC@WS2 was cleaned, dried, and Pt nanoparticles were deposited to obtain a CC@WS2 / Pt electrode. The Pt nanoparticle deposition step included: Pt deposition reaction was carried out in a three-electrode system based on Pt ion electrolyte using cyclic voltammetry, and Pt nanoparticles were deposited on the cleaned and dried CC@WS2. The cyclic voltammetry test voltage range was -0.5 to 0 V vs. RHE, the number of cyclic voltammetry test cycles was 300, and the cyclic voltammetry scan rate was 80 mV / s.

[0108] In summary, this invention discloses a method for low-energy hydrogen production and green synthesis of azofuran energetic materials based on a Pt / WS2 composite catalyst, belonging to the field of hydrogen energy and energetic materials. The technical solution provided by this invention, for the first time, replaces the high-energy-barrier oxygen evolution reaction (OER) with the azotization reaction of 3,4-diaminofuran, which has a lower oxidation potential, and couples it with water electrolysis for hydrogen production. This azotization reaction generates 3,3'-diamino-4,4'-azofuran energetic materials at the anode, offering advantages such as being green, environmentally friendly, efficient, and safe compared to traditional organic synthesis methods. Simultaneously, driven by the Pt / WS2 composite catalyst, hydrogen can be produced by applying a lower cell voltage than traditional water splitting for hydrogen production. The establishment of the coupling system in this invention achieves low-voltage, low-energy hydrogen production while simultaneously performing green electrosynthesis of azo energetic materials, achieving a dual benefit and providing a direction for the design of novel low-energy water electrolysis hydrogen production coupling systems.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for hydrogen production based on the coupling of a WS2 / Pt composite catalyst to prepare azofuran energetic materials, characterized in that, Includes the following steps: A CC@WS2 / Pt electrode was placed in a soda ash solution, and a copper oxide nanowire electrode was placed in an alkaline solution containing aminofurozan. An H-type electrolysis system separated by an anion exchange membrane was formed, with the CC@WS2 / Pt electrode as the cathode and the copper oxide nanowire electrode as the anode. Based on the H-type electrolysis system, hydrogen production was achieved at the cathode and the synthesis of 3,3'-diamino-4,4'-azofurozan energetic material at the anode was realized. in, In the steps of realizing cathode hydrogen production and anode 3,3'-diamino-4,4'-azofuran energetic material synthesis based on the H-type electrolysis system, the cathode undergoes an alkaline HER process on the surface of CC@WS2 / Pt catalyst; the anode undergoes an azotization reaction on the surface of copper oxide nanowire catalyst. The preparation method of the CC@WS2 / Pt electrode includes the following steps: adjusting the pre-obtained mixed aqueous solution of sodium tungstate and thioacetamide to a weakly acidic state to obtain an adjusted mixed aqueous solution; adding conductive carbon cloth as a carrier to the adjusted mixed aqueous solution and carrying out a hydrothermal reaction to obtain CC@WS2; cleaning and drying the CC@WS2 and depositing Pt nanoparticles to obtain the CC@WS2 / Pt electrode. In the pre-obtained aqueous solution of sodium tungstate and thioacetamide, the molar ratio of sodium tungstate to thioacetamide is 1:(5.4-6.2); the hydrothermal reaction temperature is 180℃-220℃, and the reaction time is 12 h-24 h. The carbon cloth is a carbon cloth that has been cleaned with acetone and ethanol, and the carbon cloth area is 2 cm². 2 ~6 cm 2 ; The step of depositing Pt nanoparticles includes: performing a Pt deposition reaction in a three-electrode system using a cyclic voltammetry method based on a Pt ion electrolyte, and depositing Pt nanoparticles on a cleaned and dried CC@WS2 substrate. In the step of performing Pt deposition reaction by cyclic voltammetry in a three-electrode system, the cyclic voltammetry test voltage range is -0.5 to 0 V vs. RHE, the number of cyclic voltammetry test cycles is 200 to 400, and the cyclic voltammetry scan rate is 50 to 100 mV / s.

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