A method for self-electricity-synchronous high-efficiency desulfurization and hydrogen production based on catalytic driving

Abstract

The application discloses a self-electric-synchronous high-efficiency sulfur removal and hydrogen production method based on catalytic driving, selects an electrochemical method to realize the generation of sustainable energy (H2), the removal and value-added of sulfur-containing pollutants. 2‑ Through a sulfur oxidation reaction, sulfur-containing wastewater is gradually oxidized (S Based on the ultra-low theoretical potential of the sulfur oxidation reaction and the faster electron fast transfer kinetics, the coupling of SOR and HER significantly reduces the power consumption and improves the energy efficiency; in addition, the zinc-air battery is introduced to power the entire system, which breaks the dependence on the energy supply end and realizes the synchronous sulfur removal and efficient hydrogen production with zero energy consumption. The method has the advantages of simple operation, no operation energy consumption, good treatment effect and the like, has good market competitiveness, and opens up a new road for independent green hydrogen production and the development of sustainable energy.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sewage treatment and hydrogen production by electrolysis of water, and particularly relates to a self-electricity-synchronous high-efficiency sulfur removal and hydrogen production method based on catalytic driving. BACKGROUND

[0002] In recent years, energy shortage and environmental pollution have become the focus of the world. On the one hand, with the rapid development of large-scale chemical enterprises, a series of environmental problems are brought about, especially a large amount of high-toxicity and strong-corrosion sulfur-containing wastewater generated in the production process, which seriously endangers the ecological environment and human survival and development. On the other hand, the rapid growth of the world population and industrialization has increased the global energy demand. Therefore, it is urgent to seek appropriate methods to solve the problems of environmental pollution and energy shortage.

[0003] The traditional removal methods of sulfur-containing wastewater mainly include adsorption, chemical precipitation, microbial oxidation, etc. Although these methods can effectively remove the sulfur ions (S 2- ) in water, the resource utilization of sulfur is ignored. In the process of resource utilization of sulfur by the famous Claus process in industry, the value of H2 is ignored, and a large amount of SO2 is discharged. At present, some methods (such as photocatalysis, plasma technology, etc.) have been reported for converting sulfur-containing wastewater into value-added products (i.e. H2 and S), however, these technologies also face inevitable reverse reactions, harsh thermal requirements, severe catalytic poisoning, expensive product separation and time-consuming obstacles.

[0004] Compared with other methods, the electrochemical method has advantages in the treatment of sulfur-containing wastewater due to its fast response, cost-effectiveness, ecological friendliness and easy operation. Specifically, the electrochemical sulfur oxidation reaction (SOR) is a process of converting sulfur ions into sulfur by using electric energy. Since it has an ultra-low theoretical potential and fast electron transfer kinetics, the coupling of sulfur oxidation reaction and hydrogen evolution reaction (HER) not only realizes the generation of zero-emission sustainable energy and the removal and valorization of sulfur-containing pollutants, but also solves the problems of high overpotential, slow kinetics and large energy consumption in traditional hydrogen production by electrolysis of water.

[0005] So far, the research on SOR||HER coupling system is still limited, and there are still a series of problems in these systems:

[0006] (1) Although the thermodynamically more favorable sulfur oxidation reaction is used to replace the traditional oxygen evolution reaction (OER), which significantly reduces the energy consumption, these systems still rely on external energy to supply electric energy. Whether the system can be completely self-sufficient without relying on the energy supply end is of great significance to realize the comprehensive and sustainable development of zero-energy consumption, hydrogen production and resource utilization of sulfur-containing wastewater.

[0007] (2) Traditional electrocatalysts with high HER and ORR activity are expensive, making the overall process operation cost high; the design of a low-cost electrocatalyst with multiple electrocatalytic activities (ORR, SOR and HER) is a prerequisite for realizing this novel strategy, based on the incompatibility of different reaction materials, most catalysts can only be used for a single reaction, and supporting three-phase reactions ensures consistent contact, adsorption and diffusion of materials, which is extremely challenging;

[0008] (3) In the sulfur oxidation process, the polysulfide intermediates adsorbed on the surface of the catalyst have strong affinity, hindering desorption and leading to catalyst passivation poisoning, greatly reducing catalyst activity and stability, which further increases the design difficulty. SUMMARY

[0009] This section is intended to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, abstract and title, and such simplifications or omissions cannot be used to limit the scope of the present application.

[0010] In view of the above and / or problems in the prior art, the present application is proposed.

[0011] Therefore, the purpose of the present application is to overcome the deficiencies in the prior art and provide a self-electricity-synchronous efficient desulfurization and hydrogen production method based on catalytic driving.

[0012] To solve the above technical problems, the present application provides the following technical scheme: a self-electricity-synchronous efficient desulfurization and hydrogen production method based on catalytic driving, comprising,

[0013] A zinc-air battery self-electricity system (100) is constructed, which is composed of an anode electrode (101), a cathode electrode (102), a holding device (103) and an electrolyte (104);

[0014] A hydrogen production and desulfurization system (200) is constructed, which is composed of an anode electrode (201), a cathode electrode (202), an anode chamber (203), a cathode chamber (204) and a separation membrane (205), NaOH is used as the cathode liquid, and NaOH and Na2S are used as the anode liquid to simulate sulfur-containing wastewater;

[0015] The zinc-air battery self-electricity system (100) is used as power to drive the hydrogen production and desulfurization system (200) to remove sulfur ions and convert them into S elements, and hydrogen is extracted as H2;

[0016] The anode electrode (201) and the cathode electrode (202) are electrodes with HER and SOR activity;

[0017] The anode electrode (101) is made of an ORR active material;

[0018] The electrodes for HER and SOR activity are monolithic, while the ORR active material is powdered, and both have the same active components.

[0019] As a preferred embodiment of the method described in this invention, the electrode with HER and SOR activity comprises a MoS2 / Ni9S8 / NF electrode, the preparation method of which includes,

[0020] Nickel foam pretreatment: Cut nickel foam with a thickness of 0.15-0.2 cm into 1.5×1 cm pieces. -2 Rectangular sheets, in 2.5–3 mol L -1 After sonicating in HCl solution for 20-40 minutes, sonicating in acetone for 10-15 minutes, and then sonicating in ethanol and deionized water for 10-15 minutes respectively, the surface is placed in a vacuum oven at 50-60℃ for 2-3 hours, and the surface exhibits a silver-gray metallic luster.

[0021] Preparation of MoS2 / Ni9S8 / NF: 100 mg to 120 mg of molybdenum salt, 10 mg to 30 mg of nickel salt, and 200 mg to 230 mg of sulfur-containing compound were ultrasonically dissolved in 30 mL to 40 mL of deionized water for 30 to 40 min to form a homogeneous solution.

[0022] Then, the solution is transferred to a stainless steel autoclave reactor lined with Teflon, the pretreated nickel foam is vertically placed into the solution, the reactor is sealed, and it is kept at 180-200°C in a convection oven for 18-20 hours.

[0023] After the reaction was completed, the mixture was cooled to room temperature. The nickel foam was carefully removed and rinsed several times with deionized water and ethanol. Finally, it was dried in a vacuum oven at 40–60°C for 2–3 hours to obtain the final product MoS2 / Ni9S8 / NF.

[0024] As a preferred embodiment of the method described in this invention, the ORR-active material comprises MoS2 / Ni9S8 ternary powder, and its preparation method includes,

[0025] MoS2 / Ni9S8 / NF is prepared by scraping or ultrasonic treatment to obtain MoS2 / Ni9S8 ternary powder.

[0026] In a preferred embodiment of the method described in this invention, the method for preparing the anode electrode (101) includes:

[0027] The ink was prepared by ultrasonically dispersing MoS2 / Ni9S8 ternary powder in a mixed solution of deionized water, isopropanol and Nafion.

[0028] The ink is evenly dropped on the surface of the hydrophobic carbon paper of the gas diffusion layer, and after drying, the anode electrode (101) of the zinc-air battery is prepared.

[0029] The ratio of the trifunctional catalyst powder, deionized water, isopropyl alcohol and Nafion solution is 15-25 mg:360-380 μL, 120-140 μL and 10-20 μL respectively.

[0030] As a preferred scheme of the method, the preparation method of the cathode electrode (102) comprises polishing the zinc plate with sandpaper to obtain the cathode electrode (102) of the air battery.

[0031] As a preferred scheme of the method, the electrolyte (104) is a mixed solution of KOH and Zn(OAc)2.

[0032] As a preferred scheme of the method, the volume molar concentration of the KOH and Zn(OAc)2 solution is 5-7 M and 0-1 M respectively.

[0033] As a preferred scheme of the method, the nickel salt is one or more of Ni(NO3)2·6H2O, NiCl2·6H2O, Ni(CH3COO)2 and NiSO4·6H2O.

[0034] The molybdenum salt is one or more of K2MoO4, Na2MoO4·2H2O and (NH4)6Mo7O 24 ·4H2O.

[0035] The sulfur-containing compound is one or more of Na2S, C2H5NS and CH4N2S.

[0036] As a preferred scheme of the method, the nickel salt is nickel nitrate hexahydrate, the molybdenum salt is sodium molybdate dihydrate, and the sulfur-containing compound is thioacetamide. The molar ratio of the nickel nitrate hexahydrate to the sodium molybdate dihydrate is 1:10-1:3, and the molar ratio of the metal salt to the thioacetamide is 1:3-1:6.

[0037] As a preferred scheme of the method, the NaOH and Na2S simulate the sulfur-containing wastewater, wherein the volume molar concentration of the NaOH and Na2S mixed solution is 0.5-1.5 M and 1-2 M respectively.

[0038] As a preferred scheme of the method, the NaOH is used as the cathode solution, wherein the molar concentration of the NaOH solution is 0.5-1.5 M.

[0039] The present application has the following beneficial effects:

[0040] (1) The present application is aimed at the characteristics of high toxicity, strong corrosion and difficult removal of sulfur-containing wastewater, and a electrochemical method is selected to realize the generation of sustainable energy (H2) and the removal and value-added of sulfur-containing pollutants, and the sulfur-containing wastewater is gradually oxidized (S 2- → S* → S2* → S3* → S4* → S8* → S8) and value-added through the sulfur oxidation reaction; based on the ultra-low theoretical potential of the sulfur oxidation reaction and the faster electron fast transfer kinetics, the coupling of SOR and HER significantly reduces the power consumption and improves the energy efficiency; in addition, the zinc-air battery is introduced to power the entire system, which breaks the dependence on the energy supply end and realizes simultaneous desulfurization and efficient hydrogen production with zero energy consumption; this method has the advantages of simple operation, no running energy consumption, good treatment effect, etc., and has good market competitiveness, opening up a new road for independent green hydrogen production and the development of sustainable energy.

[0041] (2) The present application is aimed at the incompatibility of different reaction materials, the high price of traditional electrocatalysts and the problem of catalyst poisoning and passivation in the sulfur oxidation process, and a MoS2 / Ni9S8 / NF three-functional catalyst is carefully designed, which effectively adjusts the electronic structure through heteroengineering and optimizes the d-band center to the Fermi level, thereby promoting various catalytic reactions; this optimization reduces the activation energy of water, enhances the adsorption of H* on the catalyst, thereby improving the HER activity; promotes the adsorption of S 2- in water, reduces the sulfur affinity at the electrode-electrolyte interface, improves the long-term SOR activity, helps the interface electron redistribution, accelerates the directional movement of electrons, establishes an efficient two-phase electron transfer channel, enhances the interaction of the catalyst with O2, and improves the ORR kinetics; in addition, a unique nanorod structure is designed, which has a large specific surface area and excellent diffusion performance, which helps to expose more active sites; in addition, the low-cost nickel-molybdenum metal is selected, which greatly reduces the cost; the experimental results prove its excellent SOR (η 100 = 0.331 V) and HER activity (η 100 = 0.143 V) and long-term stability (480 h), which lays a solid foundation for the development of self-powered simultaneous efficient desulfurization and hydrogen production process. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description, and obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained based on these drawings without creative labor. Among them:

[0043] Figure 1A schematic diagram of a self-powered and synchronous high-efficiency sulfur removal and hydrogen production coupling system in an embodiment of the present application.

[0044] Figure 2 A system physical diagram, a hydrogen production graph, and a hydrogen production physical diagram in an embodiment of the present application; wherein (a) is a self-driven SOR||HER system physical diagram constructed with MoS2 / Ni9S8 / NF as a trifunctional catalyst, (b) is a hydrogen production graph in the system over time, and (c) is a hydrogen production physical diagram.

[0045] Figure 3 Linear sweep voltammetry test graphs of sulfur oxidation (SOR) and hydrogen evolution reaction (HER) of MoS2 / Ni9S8 / NF-1-4 and platinum carbon in an embodiment of the present application; wherein (a) is a linear sweep voltammetry test graph of sulfur oxidation (SOR) of MoS2 / Ni9S8 / NF-1-4 and platinum carbon, and (b) is a linear sweep voltammetry test graph of hydrogen evolution reaction (HER) of MoS2 / Ni9S8 / NF-1-4 and platinum carbon.

[0046] Figure 4 XRD test graphs of MoS2 / Ni9S8 / NF-1, MoS2 / Ni9S8 / NF-2, and MoS2 / Ni9S8 / NF-4 in an embodiment of the present application.

[0047] Figure 5 SEM graphs of catalysts in an embodiment of the present application; wherein (a) is a low-magnification SEM graph of a MoS2 / Ni9S8 / NF-1 catalyst, (b) is a high-magnification SEM graph of the MoS2 / Ni9S8 / NF-1 catalyst, (c) is a high-magnification SEM graph of a MoS2 / Ni9S8 / NF-2 catalyst, and (d) is a high-magnification SEM graph of a MoS2 / Ni9S8 / NF-4 catalyst.

[0048] Figure 6 Stability test graphs of MoS2 / Ni9S8 / NF in an embodiment of the present application; wherein (a) is a SOR stability test graph of MoS2 / Ni9S8 / NF, and (b) is a HER stability test graph of MoS2 / Ni9S8 / NF.

[0049] Figure 7 LSV curve graphs of SOR||HER coupling systems and OER||HER coupling systems of MoS2 / Ni9S8 / NF as a double electrode. DETAILED DESCRIPTION

[0050] In order to make the above-mentioned purposes, features, and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the embodiments of the specification.

[0051] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details set forth in this description, that the present application can be practiced with other systems, and that the present application can be practiced using different techniques. Therefore, the present application is not limited to the embodiments described herein but rather the scope of the present application is to be given by the appended claims and their equivalents.

[0052] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an embodiment that is independent or alternative to other embodiments.

[0053] The present application provides a self-power-synchronous efficient sulfur removal and hydrogen production method based on catalytic driving, the main steps including:

[0054] Construction of self-power-synchronous efficient sulfur removal and hydrogen production coupling system: The overall self-driven coupling system is composed of a self-power system constructed by a zinc-air battery and a hydrogen production and sulfur removal system constructed by a sulfur oxidation reaction-hydrogen evolution reaction (SOR||HER), wherein the SOR end electrode is connected to the battery anode, and the HER end electrode is connected to the battery cathode.

[0055] The metal zinc is dissolved in the alkaline electrolyte to generate an electrochemical oxidation reaction, produce electrons, and thus form an electric current; the oxygen in the air diffuses through the reserved air-permeable layer to the catalytic layer and undergoes a three-phase electrochemical reduction reaction on the interface in contact with the electrolyte to form OH - , while realizing the conversion of chemical energy into electrical energy.

[0056] Under the power driving of the zinc-air battery system, the sulfur oxidation reaction (SOR) occurs at the anode of the SOR||HER system to remove the sulfur ions and convert them into value-added S; the hydrogen evolution reaction (HER) occurs at the cathode to generate H2.

[0057] Embodiment 1

[0058] The present embodiment provides a self-power-synchronous efficient sulfur removal and hydrogen production coupling system, the schematic diagram of the system is shown in Figure 1 , which comprises a zinc-air battery self-power system (100) and a hydrogen production and sulfur removal system (200), the zinc-air battery self-power system (100) serves as power to drive the hydrogen production and sulfur removal system (200) to remove the sulfur ions and convert them into value-added S and hydrogen evolution H2.

[0059] Specifically, the self-power system (100) constructed by the zinc-air battery is composed of an anode electrode (101), a cathode electrode (102), a containing device (103) and an electrolyte (104), the anode electrode (101) and the cathode electrode (102) are respectively fixed at the two ends of the containing device (103) and arranged in parallel;

[0060] Further, the preparation method of the anode electrode (101) is:

[0061] Take 20 mg of trifunctional catalyst powder and evenly disperse it in a mixture of 375 μL of deionized water, 125 μL of isopropyl alcohol, and 20 μL of Nafion, and ultrasonic for 30 min to prepare a mixture;

[0062] Then, 100 μL of the mixture is evenly dropped on the surface of a 1.0 x 1.0 cm carbon paper, and the electrode is dried at 60°C for 6 hours to prepare the anode electrode (101) of the air battery;

[0063] Further, the preparation method of the cathode electrode (102) is: polish the zinc plate with a thickness of 300 μm with sandpaper for 5 min to prepare the cathode electrode (102);

[0064] The cathode end is provided with a ventilation hole, and the upper end is provided with a liquid inlet. A mixed solution of 6M KOH and 0.2M Zn(OAc)2 is used as the electrolyte (104) to construct the zinc-air battery self-power system (100).

[0065] Specifically, the hydrogen production and sulfur removal system (200) is composed of an anode electrode (201), a cathode electrode (202), an anode chamber (203), a cathode chamber (204), and a separation membrane (205);

[0066] Further, the anode electrode (201) and the cathode electrode (202) are respectively fixed in the anode chamber (203) and the cathode chamber (204), and the anode chamber (203) and the cathode chamber (204) are separated by the separation membrane (205);

[0067] Further, 1M NaOH is used as the cathode liquid, and 1M NaOH and 1M Na2S are used as the anode liquid to simulate sulfur-containing wastewater, and the separation membrane (205) is a Nafion 117 membrane;

[0068] Further, the preparation method of the anode electrode (201) and the cathode electrode (202) is:

[0069] (1) Pretreatment of foamed nickel (NF): Before use, cut the foamed nickel with a thickness of 0.16 cm into a rectangular piece with a size of 1.5 x 1 cm -2 ;

[0070] Ultrasonic treat the treated foamed nickel in a 3 mol L -1 HCl solution for 30 minutes for etching to remove the oxide layer, thereby facilitating the subsequent product growth on the foamed nickel network skeleton;

[0071] Then, the sample was ultrasonicated in acetone for 15 min to remove the oil stains, followed by ultrasonication in ethanol and deionized water for 15 min, respectively, to clean the surface of the nickel foam from residual impurities. Finally, the sample was placed in a vacuum oven at 40℃ for 2h, and the surface appeared silver gray metallic luster.

[0072] (2) Preparation of molybdenum sulfide / nickel sulfide / nickel foam (MoS2 / Ni9S8 / NF-1):

[0073] 110mg (0.45mmol) of sodium molybdate dihydrate, 15mg (0.05mmol) of nickel nitrate hexahydrate, and 230mg of thioacetamide were ultrasonicated in 30mL of deionized water for 40min to form a uniform solution.

[0074] Then, the solution was transferred to a Teflon-lined stainless steel autoclave reactor, and the (1) pretreated nickel foam was vertically placed in the solution. The reactor was sealed and placed in a convection oven at 180℃ for 18h.

[0075] After the reaction was completed, the sample was cooled to room temperature.

[0076] The nickel foam was carefully removed and rinsed with deionized water and ethanol several times to remove residual salts and organic matter.

[0077] Finally, the sample was dried in a vacuum oven at 60℃ for 2.5h to obtain the final product MoS2 / Ni9S8 / NF-1.

[0078] During the reaction, sulfur-containing compounds release sulfur ion active substances, and S ions react with exposed Ni salts to form Ni9S8 particles, which then react with Mo ions to form MoS2, forming a two-phase hetero-rod structure.

[0079] X-ray diffraction (XRD) was used for measurement, as shown in Figure 4 The diffraction peaks of MoS2 / Ni9S8 / NF-1 matched well with those of Ni9S8 (JCPDS #22-1193) and MoS2 (JCPDS #17-0744), indicating the successful synthesis of the complex structure.

[0080] Scanning electron microscopy (SEM) was used to characterize the micro-morphology of the MoS2 / Ni9S8 / NF-1 prepared in this example, as shown in Figure 5 (a) shows that the entire surface of the nickel foam is uniformly covered with nanoscale product, Figure 5 (b) shows an enlarged SEM image of MoS2 / Ni9S8 / NF-1, which shows that the MoS2 / Ni9S8 nanorods are dense and uniform on the nickel foam, with a diameter of 220-300nm and a length of 1.6-2.5μm.

[0081] Specifically, the three-function catalyst powder in the preparation process of the anode electrode (101) of the self-power system (100) constructed by the zinc-air battery is the powder dispersed after ultrasonic treatment on MoS2 / Ni9S8 / NF-1.

[0082] Specifically, the anode electrode (201) is connected with the anode electrode (101) through a wire;

[0083] The cathode electrode (202) is connected with the cathode electrode (102) through a wire.

[0084] Visualization of the hydrogen gas collected by the drainage gas collection method (as shown in Figure 2 );

[0085] With only 4 mg of MoS2 / Ni9S8 / NF (20 mg / mL of ink was prepared first, and then coated on the carbon paper of the gas diffusion layer, a 1x1 cm square was drawn based on the center of the module aperture, which was used to coat the ink, and the amount of coating was 100 microliters, a total of two zinc-air batteries, and the total catalyst loading was 4 mg), a large amount of hydrogen gas (43.5 mL) can be rapidly produced. Figure 2 (b), Figure 2 (c) Calculation shows that the integrated system has a H2 production rate of 1.319 mmol h -1 -5.50 mmol / min / g catalyst of hydrogen gas per gram of catalyst, which highlights the excellent efficacy of MoS2 / Ni9S8 / NF as a three-function catalyst and demonstrates its great potential for wide application in energy conversion and storage systems.

[0086] Example 2

[0087] MoS2 / Ni9S8 / NF-2 was prepared as follows:

[0088] 122 mg (0.50 mmol) of sodium molybdate dihydrate, 0 mg of nickel nitrate hexahydrate, and 230 mg of thioacetamide were ultrasonically dissolved in 30 mL of deionized water for 40 min to form a uniform solution;

[0089] Then, the solution was transferred to a Teflon-lined stainless steel autoclave reactor, the pretreated foam nickel (same as Example 1) was vertically placed in the solution, the reactor was sealed, and the reactor was kept at 180°C in a convection oven for 18 h;

[0090] After the reaction was completed, the foam nickel was carefully removed and rinsed with deionized water and ethanol several times to remove residual salts and organic matter;

[0091] Finally, drying in a vacuum oven at 60°C for 2.5h, the final product MoS2 / Ni9S8 / NF-2 was obtained.

[0092] XRD results show that the diffraction trace of Mo is not obvious, indicating that MoS2 may exist in a low-crystalline or amorphous state in Ni9S8 / NF.

[0093] The micro-morphology of MoS2 / Ni9S8 / NF-2 prepared in this embodiment was characterized by SEM, and under high magnification, Figure 5 (c)) presents a nanowire structure with irregular surface. Compared with the thick nanorod structure of Example 1, the density of exposed active sites of Example 2 is reduced, which may reduce the electrocatalytic performance.

[0094] Example 3

[0095] MoS2 / Ni9S8 / NF-3 was prepared according to the following steps:

[0096] 61 mg (0.25 mmol) of sodium molybdate dihydrate, 74 mg (0.25 mmol) of nickel nitrate hexahydrate, and 230 mg of thioacetamide were ultrasonically dissolved in 30 mL of deionized water for 40 min to form a uniform solution;

[0097] Then, the solution was transferred to a Teflon-lined stainless steel autoclave reactor, and the pretreated nickel foam (same as Example 1) was vertically placed in the solution. The reactor was sealed and kept at 180°C in a convection oven for 18 h.

[0098] After the reaction was completed, the foam nickel was carefully removed and rinsed with deionized water and ethanol several times to remove residual salts and organic matter.

[0099] Finally, drying in a vacuum oven at 60°C for 2.5h, the final product MoS2 / Ni9S8 / NF-3 was obtained.

[0100] Example 4

[0101] MoS2 / Ni9S8 / NF-4 was prepared according to the following steps:

[0102] 0 mg of sodium molybdate dihydrate, 148 mg (0.50 mmol) of nickel nitrate hexahydrate, and 230 mg of thioacetamide were ultrasonically dissolved in 30 mL of deionized water for 40 min to form a uniform solution;

[0103] Then, the solution was transferred to a Teflon-lined stainless steel autoclave reactor, and the pretreated nickel foam (same as Example 1) was vertically placed in the solution. The reactor was sealed and kept at 180°C in a convection oven for 18 h.

[0104] After the reaction was completed, the foam nickel was carefully removed and rinsed with deionized water and ethanol several times to remove residual salts and organic matter;

[0105] Finally, the final product MoS2 / Ni9S8 / NF-4 was obtained by drying in a vacuum oven at 60°C for 2.5h. The XRD results also indicated the successful synthesis of the complex Ni9S8 / NF.

[0106] The catalyst prepared in this example was characterized by SEM for micro-morphology, which also showed a relatively uniform nanorod structure, but it is worth noting that the diameter of this nanorod was 80-200nm and the length was 1-1.8μm, as shown in Figure 5 (d). This indicates that the specific surface area of MoS2 / Ni9S8 / NF-1 may be improved compared to this example, further indicating that the introduction of Mo is beneficial to the improvement of the specific surface area, exposing more abundant catalytically active sites, which helps to improve the electrocatalytic performance.

[0107] Evaluation of electrocatalytic performance of each example:

[0108] The SOR and HER performance was evaluated using a conventional three-electrode system: the prepared sample, platinum wire and Ag / AgCl were used as the working electrode, counter electrode and reference electrode, respectively.

[0109] Linear sweep voltammetry was used to evaluate the performance of the catalysts in the examples. The hydrogen evolution reaction (HER) activity was tested in 1.0M NaOH solution, and the sulfur oxidation reaction (SOR) activity was tested in a mixture of 1.0M NaOH and 1.0M Na2S solution, and the results are shown in Figure 3 and Table 1 below.

[0110] Table 1

[0111]

[0112] As can be seen from the table, MoS2 / Ni9S8 / NF-1 has excellent SOR and HER activity, and as in the SEM images, MoS2 / Ni9S8 / NF-1 exhibits the most robust nanorod structure compared to other examples, thereby exposing more active sites, resulting in superior electrocatalytic performance.

[0113] Example 5

[0114] Evaluation of catalyst stability:

[0115] Evaluation of the stability of the MoS2 / Ni9S8 / NF catalyst is crucial to determine its feasibility for sustained practical application. The degree of voltage attenuation corresponding to a fixed current density of 100mA cm -2 was observed.

[0116] like Figure 6 As shown in (a), the stability of the sulfur oxidation reaction (SOR) is measured by 100 mA cm⁻¹. -2 The chronopotential method was used for testing. During the 480-hour experiment, the SOR potential remained relatively stable with only slight fluctuations. When fresh electrolyte was used to replace it, the potential essentially returned to its initial state, indicating that the catalyst deactivation or passivation was minimal during the long-term catalytic process.

[0117] Similarly, for HER, the potentials exhibited commendable stability over 480 hours, such as Figure 6 As shown in (b), this demonstrates the long-lasting stability of the MoS2 / Ni9S8 / NF catalyst. Therefore, this carefully designed electrode material shows promise as an excellent candidate for efficient desulfurization and hydrogen production.

[0118] Dual-electrode SOR||HER system performance:

[0119] In this dual-electrode SOR||HER system, an ultra-low applied potential of only 0.674V is required to achieve a 100mA cm⁻¹. -2 current density ( Figure 7 The voltage is far lower than the 1.895V typically required for traditional water electrolysis.

[0120] Compared to traditional methods, energy consumption is reduced by approximately 35%; in addition, the SOR||HER system also has advantages in terms of energy equivalent input and reduction of carbon dioxide emissions.

[0121] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A method for self-electro-synchronous high-efficiency desulfurization and hydrogen production based on catalytic drive, characterized in that: The zinc-air battery self-power system (100) is composed of an anode electrode (101), a cathode electrode (102), a containing device (103), and an electrolyte (104); The hydrogen production and sulfur removal system (200) is composed of an anode electrode (201), a cathode electrode (202), an anode chamber (203), a cathode chamber (204), and a separation membrane (205), and NaOH is used as the cathode liquid, and NaOH and Na2S are used as the anode liquid to simulate sulfur-containing wastewater; The zinc-air battery self-power system (100) is used as the power to drive the hydrogen production and sulfur removal system (200) to remove sulfur ions and convert them into S elements, and hydrogen is extracted as H2; The anode electrode (201) and the cathode electrode (202) are electrodes with HER and SOR activity; The anode electrode (101) is prepared from a material with ORR activity; The electrode with HER and SOR activity is a monolithic electrode, and the material with ORR activity is a powder, and both have the same active components; Preparation of MoS2 / Ni9S8 / NF: 100 mg-120 mg of molybdenum salt, 10 mg-30 mg of nickel salt, and 200 mg-230 mg of sulfur-containing compound are ultrasonically dissolved in 30 mL-40 mL of deionized water for 30-40 min to form a uniform solution, the nickel salt is nickel nitrate hexahydrate, the molybdenum salt is sodium molybdate dihydrate, and the sulfur-containing compound is thioacetamide, the molar ratio of nickel nitrate hexahydrate to sodium molybdate dihydrate is 1:10-1:3, and the molar ratio of metal salt to thioacetamide is 1:3-1:6; The electrode with HER and SOR activity comprises a MoS2 / Ni9S8 / NF electrode, and a preparation method thereof comprises the following steps: pretreating the foam nickel: cutting the foam nickel with a thickness of 0.15-0.2 cm into a rectangular piece with a size of 1.5*1 cm -2 , and then performing ultrasonic treatment in a 2.5-3 mol / L HCl solution for 20-40 min, and then performing ultrasonic treatment in acetone for 10-15 min, and then performing ultrasonic treatment in ethanol and deionized water for 10-15 min respectively, and then placing the foam nickel into a vacuum oven for heat preservation at 50-60 DEG C for 2-3 h, so that the surface presents a silver-gray metallic luster -1 . Then, the solution is transferred to a stainless steel autoclave reactor lined with Teflon, the pretreated foam nickel is vertically placed in the solution, the reactor is sealed, and the temperature is kept at 180-200°C in a convection oven for 18-20 h; After the reaction is completed, the temperature is cooled to room temperature, the foam nickel is carefully taken out and rinsed with deionized water and ethanol several times, and finally, it is dried in a vacuum oven at 40-60°C for 2-3 h to obtain the product MoS2 / Ni9S8 / NF; The material with ORR activity includes MoS2 / Ni9S8 ternary powder, and the preparation method includes ultrasonic treatment of MoS2 / Ni9S8 / NF to obtain MoS2 / Ni9S8 ternary powder; The preparation method of the anode electrode (101) includes ultrasonic dispersion of MoS2 / Ni9S8 ternary powder in a mixed solution of deionized water, isopropyl alcohol, and Nafion to obtain ink, uniform drop coating of the ink on the surface of the gas diffusion layer hydrophobic carbon paper, and preparation of the anode electrode (101) of the zinc-air battery after drying; The ratio of the three-function catalyst powder, deionized water, isopropyl alcohol, and Nafion solution is 15-25 mg:360-380 µL, 120-140 µL, and 10-20 µL, respectively; The preparation method of the cathode electrode (102) includes polishing of the zinc plate with sandpaper to obtain the cathode electrode (102) of the air battery; ​ The electrolyte (104) is a mixed solution of KOH and Zn(OAc)2.

2. The method of claim 1, wherein: The volume molar concentrations of the KOH and Zn(OAc)2 solution are 5-7 M and 0-1 M, respectively.

3. The method of claim 1 or 2, wherein: The nickel salt is one or more of Ni(NO3)2·6H2O, NiCl2·6H2O, Ni(CH3COO)2, and NiSO4·6H2O. said molybdenum salt is one or several of K2Mo04, Na2Mo04.2H20, (NH4)6Mo70 24 4H20; The sulfur-containing compound is one or more of Na2S, C2H5NS, and CH4N2S.

4. The method of claim 1, wherein: The NaOH and Na2S simulate sulfur-containing wastewater, wherein the volume molar concentrations of the NaOH and Na2S mixed solution are 0.5-1.5 M and 1-2 M, respectively; and the NaOH acts as a cathode solution, wherein the molar concentration of the NaOH solution is 0.5-1.5 M.

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