Use of a carboxylic organic as an additive for hydrogen production by electrolysis of water

Abstract

The application provides application of a carboxyl organic matter in an electrolytic water hydrogen production additive, and the catalytic performance of a catalytic electrode is improved through an electrolyte optimization strategy; meanwhile, the carboxyl organic matter has the effects of purifying impurity ions in an electrolyte and improving the stability of a catalyst; after the carboxyl organic matter is added to an alkaline electrolyte, the carboxyl organic matter additive can be preferentially combined with metal ions on the surface of the catalyst and anchored on the surface of the catalyst, finally, the electronic structure of metal elements on the surface of the catalyst is regulated, and the stability of the metal elements is improved, so that the intrinsic catalytic performance and stability of the metal elements are significantly improved. Therefore, the carboxyl organic matter of the application can realize the effects of purifying the electrolyte, stabilizing the surface of the electrode and significantly improving the OER reaction kinetics and the overall energy efficiency of an electrolytic cell by simple addition.

Description

Technical Field

[0001] This invention belongs to the field of water electrolysis hydrogen production technology, specifically relating to the application of a carboxyl organic compound as an additive in water electrolysis hydrogen production. Background Technology

[0002] With the accelerated global energy transition towards a cleaner, low-carbon model, hydrogen energy, as a widely available, clean, carbon-free secondary energy source with diverse applications, is increasingly highlighting its strategic importance. Among numerous green hydrogen production technologies, alkaline water electrolysis is one of the most widely commercialized technologies due to its mature process, relatively low cost, and ease of large-scale production. However, this technology still faces challenges in practical applications, including low energy efficiency, high energy consumption, and poor catalyst stability. This is mainly attributed to the slow kinetics of the oxygen evolution reaction (OER) at the anode, whose high overpotential and performance degradation are key bottlenecks restricting the overall energy efficiency improvement of the electrolyzer. Furthermore, traditional alkaline electrolytes (such as KOH or NaOH solutions) inevitably introduce trace metal impurity ions (such as Fe) from water sources, raw materials, equipment corrosion, or atmospheric deposition during actual industrial operation. 3+ Ca 2+ Mg 2+ These impurity ions, especially high-valence transition metal ions, readily undergo uncontrolled deposition, adsorption, or transformation on the electrode surface at the anodic operating potential, forming an inactive capping layer or composite oxide. This process not only masks the inherently high-activity sites of the electrode and alters the electrode surface microstructure, but may also trigger side reactions, leading to a further increase in anodic overpotential, catalytic activity decay, and cell voltage instability. This phenomenon is particularly pronounced in electrolysis systems operating for extended periods or using low-purity industrial raw materials, severely impacting the energy efficiency and lifespan of the electrolyzer.

[0003] To address these issues, current research primarily focuses on developing novel, highly active OER electrode materials (such as nickel-based alloys, spinel oxides, and layered double hydroxides) or on nanostructure design and surface modification of the electrodes. While these methods have achieved some success, they often involve complex material synthesis processes and high preparation costs, and they struggle to fundamentally solve the electrode "poisoning" problem caused by intrinsic impurities in the electrolyte. Another approach is to purify the electrolyte through pretreatment or circulating filtration, but this increases system complexity and operating costs.

[0004] Therefore, there is an urgent need to develop a simple, efficient, and low-cost method that can effectively suppress the negative effects of impurity ions on the OER electrode by addressing the internal chemical environment of the electrolyte. This would allow for a simple and significant improvement in the overall performance and operational stability of alkaline water electrolysis hydrogen production systems without altering existing mainstream electrode materials and electrolyzer structures. Summary of the Invention

[0005] To overcome the problems existing in the prior art, one objective of this invention is to provide an application of carboxyl organic compounds as additives for hydrogen production through water electrolysis. A second objective of this invention is to provide an electrolyte for hydrogen production through water electrolysis. A third objective of this invention is to provide an apparatus for hydrogen production through water electrolysis. A fourth objective of this invention is to provide a method for hydrogen production through water electrolysis.

[0006] This invention innovatively uses a carboxyl organic compound as an additive for hydrogen production through water electrolysis. By optimizing the electrolyte, it enhances the catalytic performance of the catalytic electrode. At the same time, the carboxyl organic compound can purify impurity ions in the electrolyte and improve the stability of the catalyst. It can purify the electrolyte, stabilize the electrode surface, and significantly improve the OER reaction kinetics and the overall energy efficiency of the electrolyzer simply by adding it.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first aspect of the present invention provides an application of a carboxyl organic compound as an additive for hydrogen production by water electrolysis, wherein the carboxyl organic compound contains carboxyl and amine groups. The carboxyl organic compounds and their salts used in this invention are potent, broad-spectrum metal complexing agents. One or more carboxyl functional groups and amine groups in their molecules can form highly stable complexes with most metal ions. When added to an alkaline electrolyte, the carboxyl organic additive preferentially complexes with metal ions on the catalyst surface, thus anchoring them there. Ultimately, this modulates the electronic structure of the metal elements on the catalyst surface and enhances their stability, thereby significantly improving their intrinsic catalytic performance and stability.

[0008] Preferably, the carboxyl organic compound includes ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, cyclohexanediaminetetraacetic acid, iminodiacetic acid, hyponitrotriacetic acid, or triethylenetetraaminehexaacetic acid, or a soluble alkali metal salt thereof.

[0009] Preferably, the water electrolysis for hydrogen production is an alkaline water electrolysis hydrogen production technology.

[0010] A second aspect of the present invention provides an electrolyte for producing hydrogen by electrolysis of water, comprising an electrolyte solution and the carboxyl organic compound described in the first aspect.

[0011] Preferably, the electrolyte solution is an aqueous solution containing an inorganic base; More preferably, the inorganic base includes at least one of sodium hydroxide and potassium hydroxide.

[0012] More preferably, the inorganic base in the electrolyte for hydrogen production by water electrolysis has a mass percentage concentration of 10%-30%.

[0013] More preferably, the mass percentage concentration of the inorganic base is any one of 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, or a range between any two.

[0014] The high-efficiency electrolyte additive of this invention is mainly used in alkaline water electrolysis hydrogen production systems based on potassium hydroxide or sodium hydroxide aqueous solutions, wherein the mass percentage concentration of alkali in the alkaline electrolyte is preferably 10%-30%. This additive has outstanding advantages such as a clearly defined function (complexing with the catalyst to improve its catalytic activity), ease of use (direct addition), good compatibility (does not affect existing electrodes and tanks), and low cost. After addition, it can effectively reduce system energy consumption, improve hydrogen production efficiency, and extend the service life of key components without changing the existing mainstream electrolyzer design and electrode materials. It is suitable for new projects or efficiency improvement retrofits of existing equipment, and has broad industrial application prospects and market promotion value.

[0015] Preferably, the concentration of carboxyl organic compounds added to the electrolyte for hydrogen production by water electrolysis is 1-150 mmol·L⁻¹. -1 .

[0016] More preferably, the concentration of the added carboxyl organic compound is 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, or 150 mmol·L. -1 Any value in or a range of values ​​between any two.

[0017] A third aspect of the present invention provides an apparatus for producing hydrogen by electrolysis of water, comprising a cathode, an anode, and an electrolytic cell; the electrolytic cell comprising the electrolyte for producing hydrogen by electrolysis of water as described in the first aspect.

[0018] Preferably, the anode comprises a substrate and a catalyst layer on its surface.

[0019] More preferably, the substrate of the anode independently includes at least one of glassy carbon electrode, nickel foam, nickel-iron foam, iron foam, copper foam, titanium foam, nickel felt, titanium felt, stainless steel felt, carbon paper, and carbon cloth.

[0020] More preferably, the catalyst in the anode includes at least one of transition metals, transition metal oxides, transition metal hydroxides, transition metal sulfides, and transition metal phosphides.

[0021] Preferably, the cathode comprises a substrate and a catalyst layer on its surface.

[0022] More preferably, the cathode substrate independently includes at least one of glassy carbon electrode, nickel foam, nickel-iron foam, iron foam, copper foam, titanium foam, nickel felt, titanium felt, stainless steel felt, carbon paper, and carbon cloth.

[0023] More preferably, the catalyst in the cathode includes at least one of transition metals, transition metal oxides, transition metal hydroxides, transition metal sulfides, and transition metal phosphides.

[0024] The fourth aspect of the present invention provides a method for producing hydrogen by electrolysis of water, using the apparatus for producing hydrogen by electrolysis of water described in the third aspect.

[0025] The beneficial effects of this invention are: This invention proposes a carboxyl organic compound as an additive for hydrogen production via water electrolysis. This compound enhances the catalytic performance of the catalytic electrode through an electrolyte optimization strategy. Simultaneously, the carboxyl organic compound purifies impurity ions in the electrolyte and improves catalyst stability. The specific mechanisms are as follows: (1) After adding the carboxyl organic compound to the alkaline electrolyte, the additive preferentially complexes with metal ions on the catalyst surface and anchors them there. This ultimately regulates the electronic structure of the metal elements on the catalyst surface and improves their stability, thereby significantly enhancing its intrinsic catalytic performance and stability; (2) The carboxyl organic compound additive fundamentally inhibits the harmful deposition and adsorption of impurity ions on the electrode surface through a "chelation scavenging" mechanism. The purified electrolyte environment allows the OER reaction to occur on a cleaner electrode surface, ensuring effective exposure and long-term stability of the catalytic active sites. Experiments show that after adding an appropriate amount of carboxyl organic compound, the onset potential of the anodic OER reaction of the catalyst is significantly reduced, the overpotential at the same current density is significantly reduced, and the overall voltage efficiency of the electrolyzer is improved. Therefore, the carboxyl organic compounds of the present invention can purify the electrolyte, stabilize the electrode surface, and significantly improve the OER reaction kinetics and overall energy efficiency of the electrolyzer simply by adding them. Attached Figure Description

[0026] Figure 1 The effect of EDTA concentration variation on NiO catalyst on its OER performance (CV curve and current density); Figure 2 The OER Tafel slope results for NiO catalysts at different EDTA concentrations are shown; AF represents concentrations of 0, 5, 10, 20, 50, and 100 mM. Figure 3 OER stability test of NiO catalyst with and without EDTA additive in electrolyte; Figure 4 The results are from SEM analysis of NiO before the reaction. Figure 5The results are SEM images of NiO after the reaction in the presence of EDTA. Figure 6 The results are SEM images of NiO after the reaction in the absence of EDTA. Figure 7 The effect of EDTA concentration variation on Ni3Fe1LDH catalyst on its OER performance (CV curve (A) and current density (B)); Figure 8 The OER Tafel slope results for Ni3Fe1LDH catalyst at different EDTA concentrations are shown; AG represents concentrations of 0, 5, 10, 20, 50, 100, and 150 mM, respectively. Figure 9 OER stability test of Ni3Fe1LDH catalyst with and without EDTA additive in electrolyte; Figure 10 The results show the enhanced OER performance of each catalyst in the presence of EDTA additive in the electrolyte. Figure 11 To test the OER performance (CV curve) of NiO catalyst with and without acetic acid (CH3COOH) additive in the electrolyte; Figure 12 The HER performance (LSV curve) of NiFe-LDH catalyst was tested with and without EDTA additive in the electrolyte. Detailed Implementation

[0027] The present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the raw materials used in the following embodiments can be obtained from conventional commercial channels or prepared and isolated through simple synthesis; unless otherwise specified, the processes employed are conventional processes in the art.

[0028] Example 1 Firstly, this embodiment uses nickel oxide (NiO) as a model catalyst and ethylenediaminetetraacetic acid (EDTA) as a typical carboxyl-containing organic compound to investigate the effect of carboxyl-containing organic additives on the OER performance of the catalyst in the alkaline OER reaction process. Electrolyte additive EDTA and strong base potassium hydroxide (KOH) were added to the electrolytic cell, and a certain amount of deionized water was added to dissolve them, thus obtaining a KOH solution containing EDTA additive. The concentration of EDTA was 20 mmol / L. -1 The concentration of KOH is 1 mol L. -1A test apparatus for EDTA-assisted water electrolysis to produce hydrogen was constructed by placing NiO as the anode electrode and a carbon rod as the cathode material in an electrolyzer. The synergistic effect of EDTA-assisted NiO water electrolysis to produce hydrogen was evaluated using linear voltammetry at room temperature. Figure 1 As shown in Table 1, the OER onset potential of the NiO catalyst is 1.549 V (1 mA cm⁻¹) when there is no EDTA in the electrolyte. -2 The overpotential is 1.628 V (10 mA cm⁻¹). -2 Furthermore, its Tafel slope is as high as 103.9 mV dec -1 When the concentration of EDTA in the electrolyte gradually decreased from 5 mmol / L... –1 Increased to 100 mmol L –1 At that time, the OER onset potential of the NiO catalyst gradually decreased to 1.485 V. However, its overpotential and Tafel slope gradually increased with the EDTA concentration from 0 mmol / L. –1 Increased to 100 mmol L –1 It shows a trend of first increasing and then slowly decreasing. Figure 2 When the EDTA concentration is 20 mmol / L... –1 At that time, the NiO catalyst exhibited the lowest overpotential and Tafel slope, at 1.561 V and 66.7 mV dec, respectively. -1 In summary, appropriate amounts of EDTA can significantly enhance the OER performance of NiO catalysts, while excessive EDTA weakens this enhancement. The strongest enhancement effect on the OER performance of NiO catalysts was observed when the EDTA concentration was 20 mM, with the current at the same potential increasing by approximately 6.3 times, from approximately 10 mA cm⁻¹. -2 It increased to 63.2 mA cm⁻¹ -2 .

[0029] Table 1. Effects of EDTA concentration variation on NiO catalyst on OER initiation potential, overpotential, and Tafel slope.

[0030] Example 2 Subsequently, this embodiment continued to use NiO as a model catalyst to investigate the stability of EDTA in the OER reaction process. The experimental setup was the same as in Example 1. Figure 3 As shown, when there is no EDTA in the electrolyte, the NiO catalyst exhibits a constant current (10 mA cm⁻¹) over 24 h. -2During the testing process, the required voltage continuously increased, eventually rising from approximately 1.63 V to 1.65 V. However, when 20 mM EDTA was present in the electrolyte, the NiO catalyst exhibited excellent stability throughout the 24-hour testing period, with the voltage remaining consistently at approximately 1.56 V. In contrast, the EDTA additive allowed the NiO catalyst to achieve the same OER current (10 mA cm⁻¹). -2 The required voltage is reduced by about 70 mV, demonstrating an extremely excellent boosting effect.

[0031] Furthermore, the morphological changes of the catalyst before and after the reaction were compared using SEM. For example... Figure 4-6 As shown, it can be observed that the NiO catalyst does not change significantly before and after the reaction in the presence of EDTA. However, in the absence of EDTA, the surface morphology of the NiO catalyst undergoes a dramatic change, transforming from a stalactite-like structure to granular particles. It is important to note, however, that even with such a significant morphological change, the change in its catalytic performance is actually not significant. Figure 3 Conversely, adding EDTA to the electrolyte can significantly improve the OER performance of NiO while also significantly suppressing its surface phase transition. However, the improvement in its catalytic activity is not causally related to its suppression of the catalyst phase transition process.

[0032] Example 3 Subsequently, this embodiment used nickel-iron hydrotalcite (Ni3Fe1LDH) as a model catalyst to investigate the effect of EDTA on the OER reaction under operating conditions (6.0 M KOH). Electrolyte additive EDTA and strong base potassium hydroxide (KOH) were added to the electrolyzer, and a certain amount of deionized water was added to dissolve them, thus obtaining a KOH solution containing EDTA additive. The concentration of EDTA was 150 mmol / L. -1 The concentration of KOH is 6 mol L. -1 A test apparatus for EDTA-assisted water electrolysis to produce hydrogen was constructed in this embodiment, using Ni3Fe1LDH as the anode electrode and a carbon rod as the cathode material in an electrolyzer. The synergistic effect of EDTA-assisted Ni3Fe1LDH water electrolysis to produce hydrogen was evaluated at room temperature using cyclic voltammetry. Figure 7 As shown in Table 2, the OER onset potential of the Ni3Fe1LDH catalyst is approximately 1.469 V (1 mA cm⁻¹) when EDTA is absent in the electrolyte. -2 The overpotential is 1.489 V (10 mA cm⁻¹). -2 Furthermore, its Tafel slope is as high as 96.6 mV dec -1 When the concentration of EDTA in the electrolyte gradually decreased from 5 mmol / L... –1Increased to 150 mmol L –1 At that time, the OER onset potential of the NiO catalyst gradually decreased to 1.443 V. However, its overpotential and Tafel slope generally increased with the EDTA concentration from 0 mmol / L. –1 Increased to 100 mmol / L –1 It shows a trend of first increasing and then slowly decreasing. Figure 8 Specifically, when the EDTA concentration is 50 mmol / L... –1 At this concentration, the Ni3Fe1LDH catalyst exhibited the lowest overpotential, at 1.479 V. When the EDTA concentration was 100 mmol / L... –1 At that time, the Ni3Fe1LDH catalyst exhibited the lowest Tafel slope, at 37.5 mV dec. -1 In summary, an appropriate amount of EDTA can significantly enhance the OER performance of the Ni3Fe1LDH catalyst, while excessive EDTA weakens this enhancement. This is consistent with the previous findings. When the concentration of EDTA is 100 mM, it exhibits the strongest enhancing effect on the OER performance of the Ni3Fe1LDH catalyst, increasing the current at the same potential by approximately 1.8 times, from approximately 10 mA cm⁻¹. -2 It increased to 17.9 mA cm⁻¹ -2 These results demonstrate that, under operating conditions (6.0 M KOH), EDTA additives can also improve the OER performance of catalysts.

[0033] Table 2. Effects of EDTA concentration variation on OER onset potential, overpotential, and Tafel slope of Ni3Fe1LDH catalyst.

[0034] Example 4 Subsequently, this embodiment continued to use Ni3Fe1LDH as a model catalyst to investigate the effect of EDTA under the following conditions (6.0M KOH, 500 mA cm⁻¹). -2 The OER stability of the test was assessed. The test setup was the same as in Example 3. Figure 9 As shown, when there is no EDTA in the electrolyte, Ni3Fe1LDH reaches 500 mA cm⁻¹ during a long-term test exceeding 200 h. -2 The required voltage is approximately 1.81 V. However, when 100 mM EDTA is present in the electrolyte, the Ni3Fe1LDH catalyst exhibits excellent stability throughout the testing process, with its voltage remaining consistently at approximately 1.74 V. In contrast, the EDTA additive allows the NiO catalyst to achieve the same OER current (10 mA cm⁻¹). -2The required voltage is reduced by about 60 mV, demonstrating an extremely excellent boosting effect.

[0035] Example 5 Subsequently, this embodiment further investigated the effect of EDTA additives on the OER reaction on other catalysts such as Ni-based, Co-based, Fe-based, Cu-based oxides, hydroxides, sulfides, phosphides, metals, and alloys. Specifically, the catalysts involved included nickel oxide (NiO) and cobalt oxide (CoO). y ), copper oxide (CuO) y ), ferric oxide (Fe2O3), nickel-iron oxide (Ni1Fe2O3) y NiFe2O y ), iron cobalt oxide (Fe1Co1O) y Nickel copper oxide (Ni1Cu1O) y ), iron-cobalt-nickel ternary oxide (FeCoNiO) y Nickel hydroxide (Ni(OH)2), cobalt hydroxide (Co(OH)2), copper hydroxide (Cu(OH)2), nickel-copper hydroxide (NiCu(OH)2), nickel-cobalt hydroxide (NiCo(OH)2), copper-cobalt hydroxide (CuCo(OH)2), nickel sulfide (NiS) y ), cobalt sulfide (CoS) y Nickel phosphide (NiP) y Cobalt phosphide (CoP) y The following materials were used: nickel foam (Ni foam), cobalt plate (Co plate), copper foam (Cufoam), iron foam (Fe foam), nickel-iron foam (NiFe foam), iron-cobalt alloy plate (FeCo plate), iron-cobalt-nickel alloy plate (FeCoNi plate), carbon paper, silver plate (Ag plate), gold plate (Au plate), platinum plate (Pt plate), platinum-carbon electrode (Pt / C), and ruthenium oxide (RuO2). Furthermore, this embodiment also investigated the effect of EDTA additive on the OER reaction on some noble metal catalysts. Electrolyte additive EDTA and strong base potassium hydroxide (KOH) were added to the electrolytic cell, and a certain amount of deionized water was added to dissolve them, thereby obtaining a KOH solution containing EDTA additive. The concentration of EDTA was 150 mmol / L. -1 The concentration of KOH is 6 mol L. -1 The aforementioned materials were used as the anode electrode, and a carbon rod was placed as the cathode material in an electrolyzer, thus constructing the experimental apparatus for EDTA-assisted water electrolysis to produce hydrogen in this embodiment. Finally, the synergistic effect of EDTA-assisted water electrolysis to produce hydrogen was evaluated using cyclic voltammetry at room temperature. Figure 10As shown, for all the catalysts studied, the addition of EDTA to the electrolyte effectively reduced the onset potential of the OER. For most catalysts, EDTA additives effectively improved their Tafel slope, i.e., improved their OER reaction kinetics. In summary, EDTA additives effectively improved the OER performance of Ni-based, Co-based, Fe-based, Cu-based oxides, hydroxides, sulfides, phosphides, metal and alloy catalysts, as well as noble metal catalysts, achieving an OER of 10 mA cm⁻¹ at the same potential (without the influence of EDTA). -2 The OER current at the potential was increased by approximately 1.1-6.7 times.

[0036] Example 6 Subsequently, using NiO as a model catalyst and acetic acid as a typical example of other carboxyl-based organic additives, this embodiment further investigated the influence of carboxyl-based organic additives on the OER performance of the catalyst. The carboxyl group is a key structural element in the interaction between the carboxyl-based organic additive and the catalytic electrode surface. Other auxiliary active groups (e.g., amino, sulfonic acid groups, etc.) can affect the interaction between the carboxyl-based organic additive and the catalytic electrode surface, thus affecting its synergistic effect in assisting water electrolysis for hydrogen production. Acetic acid (chemical formula CH3COOH) was selected here. Figure 11 As shown, adding acetic acid to the electrolyte can significantly improve the OER performance of NiO catalysts.

[0037] Example 7 Subsequently, this embodiment uses NiFe-LDH as a model catalyst to investigate in detail the promoting effect of EDTA in the electrolyte when used as a HER catalyst. Figure 12 As shown, the presence or absence of EDTA in the electrolyte has almost no effect on the HER performance of the NiFe-LDH catalyst. This indicates that when the EDTA effect is applied to electrode materials for water electrolysis to produce hydrogen, it is mainly achieved by improving the properties of the anode electrode material and thus enhancing its OER catalytic activity. This mechanism can be applied to the independent anode chamber of anion exchange membrane water electrolysis (AEM) technology, and for some noble metal catalysts, it can also be applied to the independent anode chamber of proton exchange membrane water electrolysis (PEM).

[0038] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. The application of a carboxyl organic compound as an additive in water electrolysis for hydrogen production, characterized in that, The carboxylated organic compound contains carboxyl and amine groups.

2. The application according to claim 1, characterized in that, The carboxyl organic compounds include ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, cyclohexanediaminetetraacetic acid, iminodiacetic acid, hypozinotriacetic acid, or triethylenetetraaminehexaacetic acid, or their soluble alkali metal salts.

3. An electrolyte for hydrogen production by water electrolysis, characterized in that, Includes electrolyte solutions and carboxylated organic compounds as described in claim 1 or 2.

4. The electrolyte for hydrogen production by water electrolysis according to claim 3, characterized in that, The electrolyte solution is an aqueous solution containing an inorganic base; Preferably, the inorganic base includes at least one of sodium hydroxide and potassium hydroxide.

5. The electrolyte for hydrogen production by water electrolysis according to claim 3, characterized in that, In the electrolyte for hydrogen production via water electrolysis, the concentration of added carboxyl organic compounds is 1-150 mmol·L⁻¹. -1 .

6. The electrolyte for hydrogen production by water electrolysis according to claim 4, characterized in that, In the electrolyte used for hydrogen production by water electrolysis, the inorganic base has a mass percentage concentration of 10%-30%.

7. An apparatus for producing hydrogen by electrolysis of water, characterized in that, It includes a cathode, an anode, and an electrolytic cell; the electrolytic cell includes the electrolyte for hydrogen production by water electrolysis as described in any one of claims 3-6.

8. The apparatus for producing hydrogen by electrolysis of water according to claim 7, characterized in that, The substrate in the anode or the cathode independently includes at least one of glassy carbon electrode, nickel foam, nickel-iron foam, iron foam, copper foam, titanium foam, nickel felt, titanium felt, stainless steel felt, carbon paper, and carbon cloth.

9. The apparatus for producing hydrogen by electrolysis of water according to claim 7, characterized in that, The catalyst in the anode or the cathode includes at least one of transition metals, transition metal oxides, transition metal hydroxides, transition metal sulfides, and transition metal phosphides.

10. A method for producing hydrogen by electrolysis of water, characterized in that, The apparatus for producing hydrogen by electrolysis of water as described in any one of claims 7-9.

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