JP2011184789A - Hydrogen production method, hydrogen production apparatus and power generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen production method for generating hydrogen at room temperature, in which the generated amount of hydrogen is controlled if need and a hydride is repeatedly used as a hydrogen storage source. <P>SOLUTION: Hydrogen is generated by electrolyzing an electrolyte 3 using an anode 5 and cathode 6 each comprising platinum, palladium, nickel or iron, wherein the electrolyte is prepared by dissolving a supporting electrolyte such as ammonia borane (NH<SB>3</SB>BH<SB>3</SB>) and lithium perchlorate in an organic solvent such as methanol and ethanol and housed in an electrolyte tank 1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hydrogen production method, a hydrogen production apparatus, and a power generation system.

  In recent years, energy consumption by humans has increased, and depletion of fossil fuels has been regarded as a problem. In addition, carbon dioxide released in large quantities is considered to be a causative agent for global warming, and regulations on emissions are urgently needed. In addition, nitrogen oxides (NOx) and sulfur oxides (SOx) also cause pollution such as acid rain. As a new energy source for solving the above-mentioned problems, hydrogen that can be used as fuel for fuel cells and that emits only water is attracting attention.

However, since hydrogen is a gas at room temperature, its storage method is difficult. Currently used hydrogen storage methods are (1) stored as high pressure gas, (2) stored as liquid hydrogen, (3) stored in hydrogen storage alloy, (4) stored by adsorbing or adding to organic materials, (5 ) There are five types of storage as hydrides.
Among these hydrogen storage methods, a hydride such as ammonia borane has an excellent hydrogen content per mass, and therefore, a method of taking out hydrogen from the hydride has attracted particular attention (see, for example, Patent Document 1).

Special table 2008-528438 gazette

However, in the conventional method of extracting hydrogen from hydride, hydrogen is generated by heating the hydride, so energy for heating is required, and the generation of hydrogen is adjusted as necessary. Is difficult. In the conventional method, by heating the hydride to generate hydrogen, a by-product is generated at the same time, and this by-product may make it difficult to repeatedly use the hydride as a hydrogen storage source.
The present invention has been made in view of such circumstances, can generate hydrogen at room temperature, can adjust the amount of hydrogen generation as necessary, and repeatedly uses hydride as a hydrogen storage source. A hydrogen production method that can be used is provided.

The present invention provides a method for producing hydrogen, characterized in that hydrogen is generated by electrolyzing an electrolytic solution in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent.

According to the present invention, by electrolyzing an electrolytic solution in which ammonia borane and a supporting electrolyte are dissolved in an organic solvent, a dehydrogenation reaction of ammonia borane can proceed electrochemically, and hydrogen can be generated. . In addition, this dehydrogenation reaction can proceed at a temperature of about room temperature.
According to the present invention, when hydrogen is to be generated, electrolysis can be performed to generate hydrogen, and when hydrogen is not desired to be generated, the electrolysis is stopped so that hydrogen is not generated or the amount generated is reduced. be able to. This makes it possible to adjust the generation of hydrogen as required.
According to the present invention, the dehydrogenation reaction of ammonia borane proceeds on the surface of the electrode where electrolysis is performed, so that hydrogen generation can be completely stopped by pulling up the electrode from the electrolyte.
According to the present invention, since an organic solvent in which ammonia borane and a supporting electrolyte are dissolved is used as an electrolytic solution, hydrogen can be generated without generating boric acid or the like that is difficult to reduce to ammonia borane. Therefore, the reaction product generated by the dehydrogenation reaction of ammonia borane can be hydrogenated and reduced to ammonia borane, and ammonia borane contained in the electrolyte can be repeatedly used as a hydrogen storage source.
According to the present invention, since ammonia borane having a hydrogen mass density of 19.6% by mass is used as a hydrogen storage source, more hydrogen can be generated.

It is the schematic which shows the structure of the hydrogen production apparatus of one Embodiment of this invention. It is the schematic which shows the structure of the electric power generation system of one Embodiment of this invention. It is the schematic of the apparatus which performed the cyclic voltammetry experiment. It is a cyclic voltammogram in a methanol solution. It is a cyclic voltammogram with respect to the methanol solution containing ammonia borane and methanol not containing ammonia borane. It is a cyclic voltammogram of a methanol solution containing ammonia borane. It is a graph which shows the time-dependent change of an oxidation current when carrying out constant potential electrolysis. It is a graph which shows the time-dependent change of the amount of hydrogen generation on the working electrode side. It is a graph which shows the time-dependent change of the amount of hydrogen generation on the counter electrode side. It is a graph which shows the relationship between the amount of electricity obtained, and the amount of hydrogen generation on the working electrode side. It is a graph which shows the relationship between the obtained electric quantity and the amount of hydrogen generation on the counter electrode side. It is a graph which shows the time-dependent change of an electric current at the time of performing constant potential electrolysis with 0.5V vs. Ag / AgCl. It is a graph which shows the relationship between the amount of electricity obtained, and the amount of hydrogen generation on the working electrode side. It is a graph which shows the relationship between the obtained electric quantity and the amount of hydrogen generation on the counter electrode side. It is a graph which shows the electric current change by the constant potential electrolysis in 1.1V vs. Ag / AgCl. It is a graph which shows the relationship between the amount of electricity obtained, and the amount of hydrogen generation on the working electrode side. It is a graph which shows the relationship between the obtained electric quantity and the amount of hydrogen generation on the counter electrode side.

The hydrogen production method of the present invention is characterized in that hydrogen is generated by electrolyzing an electrolytic solution in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent.

Ammonia borane is a compound that can be represented by the chemical formula NH ₃ BH ₃ . In the drawings, ammonia borane is abbreviated as AB.

In the hydrogen production method of the present invention, the organic solvent is preferably an alcohol.
Thereby, ammonia borane can be dissolved in an organic solvent.
In the hydrogen production method of the present invention, the electrolytic solution preferably has an ammonia borane concentration of 10 mmol · dm ⁻³ or more and 100 mmol · dm ⁻³ or less.
Thereby, the dehydrogenation reaction of ammonia borane can proceed electrochemically, and hydrogen can be generated.

The present invention includes an electrolytic bath for storing an electrolytic solution in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent, an anode, and a cathode, and a voltage is applied between the anode and the cathode. Thus, a hydrogen production apparatus for generating hydrogen from the anode or the cathode is also provided.
With this hydrogen production apparatus, the dehydrogenation reaction of ammonia borane can proceed electrochemically, and hydrogen can be generated.
In the hydrogen production apparatus of the present invention, the anode and the cathode are preferably made of platinum, palladium, nickel, copper or iron.
Thereby, hydrogen can be generated from the anode or the cathode.

The present invention also provides a power generation system including the hydrogen production apparatus of the present invention and a fuel cell capable of using hydrogen generated from the hydrogen production apparatus as a fuel.
With the power generation system of the present invention, hydrogen can be generated when electricity is required, and the fuel cell can generate power.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The configurations shown in the drawings and the following description are merely examples, and the scope of the present invention is not limited to those shown in the drawings and the following description.

Diagram 1 of the hydrogen production device is a schematic diagram showing a configuration of a hydrogen production device according to an embodiment of the present invention.

The hydrogen production method of this embodiment is characterized in that hydrogen is generated by electrolyzing an electrolytic solution 3 in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent.
The hydrogen production apparatus 20 of this embodiment includes an electrolytic solution tank 1 that stores an electrolytic solution 3 in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent, an anode 5, and a cathode 6. Hydrogen is generated from the anode 5 by applying a voltage between the cathode 5 and the cathode 6.

Further, the hydrogen production apparatus 20 of the present embodiment may further include a reference electrode 8.
In addition, the hydrogen production apparatus 20 of the present embodiment has an electrolytic cell provided with an electrolytic solution tank 1, an anode 5, a cathode 6, a reference electrode 8, an injection port for the electrolytic solution 3, a discharge port, a generated gas extraction port, and the like. May be.
Hereinafter, the hydrogen production method, the hydrogen production apparatus 20, and the power generation system of this embodiment will be described.

1. Hydrogen Production Device The hydrogen production device 20 is a device that generates hydrogen by electrolyzing an electrolytic solution 3 in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent. The power source used for the electrolysis is not particularly limited. For example, a fuel cell into which hydrogen generated by a hydrogen production apparatus is introduced may be used, or a solar cell may be used.

2. Electrolytic Solution Tank The electrolytic solution tank 1 is a container that can store the electrolytic solution 3 and is not particularly limited as long as the anode 5 and the cathode 6 can be brought into contact with the electrolytic solution 3. For example, FIG. The H-shaped electrolytic solution tank 1 as shown in FIG. Further, the electrolytic solution tank 1 may include a gas discharge path 15. As a result, the gas generated from the anode 5 or the cathode 6 can be recovered. Further, the electrolytic solution tank 1 may be one in which the electrolytic solution 3 can flow.
In the electrolytic solution tank 1, a tank for storing the electrolytic solution 3 for storing the anode 5 and a tank for storing the electrolytic solution 3 for storing the cathode 6 may be separated by a diaphragm or an ion exchange membrane.

3. Electrolytic Solution The electrolytic solution 3 is an electrolytic solution in which ammonia borane and a supporting electrolyte are dissolved in an organic solvent. As a result, the oxidative dehydrogenation reaction of ammonia borane can proceed electrochemically at the anode, and hydrogen can be generated. Further, the electrolytic solution 3 may be an organic electrolytic solution.
Ammonia borane is a substance represented by the chemical formula NH ₃ BH ₃ and has a high hydrogen mass density of 19.6% by mass. Moreover, it is possible to generate 3 mol of hydrogen gas at a maximum from 1 mol of ammonia borane, and the amount of hydrogen generated per mass is very large. In addition, the oxidative dehydrogenation reaction of ammonia borane proceeds electrochemically in the hydrogen generator of the present embodiment to generate hydrogen, and then the reaction product of ammonia borane is reduced to ammonia borane by hydrogenation. Is possible. This makes it possible to repeatedly use ammonia borane as a hydrogen storage source.

It is better that the electrolyte 3 does not contain water as much as possible. The water contained in the electrolytic solution 3 may cause generation of a substance such as boric acid due to the hydrolysis reaction of ammonia borane.
This can prevent substances such as boric acid from being generated by the oxidative dehydrogenation reaction of ammonia borane. It is difficult to reduce boric acid to ammonia borane by performing a reduction treatment. For this reason, when boric acid is generated, it is a cause of hindering repeated use of ammonia borane as a hydrogen storage source. Therefore, it is considered that the ammonia borane contained in the electrolytic solution 3 can be repeatedly used as a hydrogen storage source.

  The organic solvent contained in the electrolytic solution 3 is preferably alcohol. For example, methanol, ethanol, propanol, 2-propanol, ethylene glycol, or glycerin. In addition, by using methanol as the organic solvent, it is possible to proceed a reaction for generating hydrogen by reducing methanol at the cathode 6.

  Moreover, the electrolyte solution 3 contains a supporting electrolyte. Thereby, the electrolyte solution 3 can have electroconductivity. Examples of the supporting electrolyte include lithium perchlorate and lithium hexafluoroborate.

  Moreover, the temperature of the electrolyte solution 3 is room temperature or 0 degreeC-50 degreeC, for example. Thus, hydrogen generation due to thermal decomposition of ammonia borane can be suppressed, and adjustment of the amount of hydrogen generation can be facilitated by adjusting the voltage applied between the anode 5 and the cathode 6.

4). Anode and Cathode The anode 5 and the cathode 6 are not particularly limited as long as a voltage can be applied to both electrodes, an oxidation reaction can proceed at the anode, and a reduction reaction can proceed at the cathode.
For example, the anode 5 and the cathode 6 may be made of an 8-11 group transition metal such as platinum, palladium, nickel, copper, and iron. Moreover, these metal plates etc. can be used. In addition, when platinum is used for the anode 5 and the cathode 6, since platinum has a high catalytic activity, it can efficiently generate oxidative dehydrogenation of ammonia borane and generate hydrogen more efficiently. Can do. However, since platinum has a high catalytic activity, the oxidative dehydrogenation reaction of ammonia borane proceeds even if the voltage is not applied between the anode 5 and the cathode 6, although the reaction rate is slow. However, this progress can be completely stopped by pulling up the anode 5 and the cathode 6 from the electrolytic solution 3.

  Further, when a voltage is applied between the anode 5 and the cathode 6, hydrogen can be generated at the anode 5. When the voltage applied between the anode 5 and the cathode 6 is eliminated, the amount of generated hydrogen is reduced. be able to. Thus, the amount of hydrogen generated can be adjusted by adjusting the voltage applied between the anode 5 and the cathode 6, and hydrogen can be generated as necessary.

The voltage applied between the anode 5 and the cathode 6 is not particularly limited as long as hydrogen can be generated from the anode 5, but for example, a voltage of 1V to 3V can be applied to generate hydrogen.
The potential of the anode 5 can be set to 0.1 V to 0.5 V with respect to the silver-silver chloride electrode.

5. Reference electrode The reference electrode 8 is not particularly limited as long as it is an electrode that shows a stable potential in the electrolytic solution 3 and serves as a reference for calculation, measurement, and setting of the electrode potential. For example, it is a silver-silver chloride electrode.

6). Power Generation System FIG. 2 is a schematic diagram showing the configuration of the power generation system of this embodiment.
The power generation system of this embodiment includes a hydrogen production device 20 and a fuel cell 26 that can use hydrogen generated from the hydrogen production device 20 as fuel.
Since the hydrogen production apparatus 20 can generate hydrogen as necessary, hydrogen can be supplied to the fuel electrode 24 of the fuel cell 26 when power generation is necessary. Thus, the fuel cell 26 can generate power when electricity is required.

Experiment 1. Production of electrodes Production of anode (working electrode) 5 and cathode (counter electrode) 6 5 × 5 mm platinum plate (anode 5) and 10 × 10 mm platinum plate (cathode 6) (Niraco, PT-353382, thickness 0.1 mm ) And a platinum wire (Niraco, PT-351385, wire diameter 0.50 mm), anode 5 and cathode 6 were produced. Further, the produced anode 5 and cathode 6 were subjected to electrolytic polishing. For electropolishing, a cell is constructed using a reversible hydrogen electrode (RHE) as the reference electrode and 0.5MH ₂ SO ₄ (WAKO, 190-04675, 96 +%, FW = 98.08) as the electrolyte, and high purity nitrogen After bubbling (Sumitomo Seika, 99.999%) for 10 minutes, a potential range of 0.05 to 1.2 V was performed at a scanning speed of 100 mVs ⁻¹ until a cyclic voltammogram peculiar to Pt was obtained.

Preparation of Reference Electrode A silver wire was polished with sandpaper in a glove bag filled with argon, and a silver / silver chloride ink for reference electrode (BAS, code No. 011464) was applied. Thereafter, a silver wire was sealed in the sample tube and dried for one day. Vycor glass (BAS, Cat. No. 012182, diameter 2.73 mm, height 4 mm) was fixed to the tip of the glass tube with a heat-shrinkable tube (BAS, Cat. No. 012183, diameter 3 mm).
Lithium chloride (Mitsuwa, 39141, 99%, FW = 42.40, hereinafter referred to as LiCl) was dried at 120 ° C. under reduced pressure for 3 hours. LiCl naturally cooled while vacuuming is put in a glove box, 10 ml of dehydrated methanol (WAKO, 132-12385, 99.8%, FW = 32.04) is poured, the sample tube lid is closed tightly, and Teflon tape is added. Was taken out of the glove box. A saturated lithium chloride solution was prepared by immersing in a thermostatic bath containing 50 ° C. water for 30 minutes, and allowing to stand in a glove box again after natural cooling.
Using these, a reference electrode was produced in the glove box.

2. Cyclic voltammetry experiment Cyclic voltammetry was performed to investigate the electrochemical properties of ammonia borane in methanol. ALS-730C (BAS) was used as the apparatus. In the glove box, 10, 20, and 30 mM ammonia borane and lithium perchlorate (WAKO, 123-05741, 98 +%, FW = 106.39, hereinafter referred to as LiClO ₄ ) are dissolved in 10 ml of dehydrated methanol for electrolysis. A cell as shown in FIG. 3 was constructed as a liquid. The cell was removed from the glove box and high purity nitrogen was bubbled for 15 minutes. Cyclic voltammetry was performed at room temperature with a scanning speed of 20 mVs ⁻¹ in various potential ranges. The same measurement was performed for an electrolyte solution containing no ammonia borane. LiClO _{4 as the} supporting electrolyte was dehydrated at 120 ° C., and the concentration was 0.5M.

Methanol potential window
A cyclic voltammogram in a methanol solution containing N ₂ saturated, 0.5M LiClO ₄ is shown in FIG. From this figure, when Pt was used for the electrode, an oxidation current was observed from around 1.2 V in the potential scan in the positive potential direction. Further, in the potential scanning in the negative potential direction, a reduction current was observed from around −0.8 V, and bubbles were generated from the electrodes. This bubble is considered to be hydrogen produced by the reaction of Chemical Formula 1 on the Pt electrode.

(Chemical formula 1)
^{_{2 CH 3 OH + 2 e -}} → 2 CH 3 O - + H 2

  From these results, it was judged that the potential window of methanol was −0.8 V to 1.2 V when Pt was used for the electrode.

Cyclic voltammogram of a solution containing ammonia borane Cyclic voltammogram in a potential range of −0.7 V to 0.7 V vs. Ag / AgCl for methanol solutions containing 10, 20, 30 mM ammonia borane and methanol containing no ammonia borane. Is shown in FIG. A Pt plate was used as the electrode. In this potential range, almost no oxidation current flowed when ammonia borane was not included. On the other hand, when ammonia borane was contained, an oxidation current was observed from around −0.3 V at any concentration, and reached a peak at around 0 V. Further, as the concentration of ammonia borane increased, the oxidation current also increased, and bubbles were observed at the working electrode. Therefore, it is considered that an oxidative dehydrogenation reaction of ammonia borane occurs in a methanol solution containing ammonia borane. FIG. 6 shows a cyclic voltammogram of a methanol solution containing 10 mM ammonia borane in a potential range of −1.2 V to 1.6 V vs. Ag / AgCl. Even in this potential range, an oxidation peak was observed near 0V. In addition, the current decreased slightly near 0.5V, and a large oxidation current flowed from around 1.2V. Further scanning to the negative potential side showed an oxidation peak in the vicinity of 0.85V. When no ammonia borane is contained, since such a peak is not observed, it is considered that the peak is related to the oxidation reaction of ammonia borane. Therefore, constant potential electrolysis at 0.1 V, 0.5 V, and 1.1 V was performed, and the gas generated by the electrochemical oxidation reaction of ammonia borane was qualitatively and quantitatively analyzed by gas chromatography.

3. Constant-potential electrolysis measurement To investigate the electrochemical dehydrogenation of ammonia borane, a constant-potential electrolysis measurement was performed. The apparatus used was ALS-730C (BAS). A cell as shown in FIG. 1 was constructed, and a silicone sealant (GE Toshiba Silicone, 6-377-01, TSE382C) was applied and dried overnight. In the glove box, 10 mM ammonia borane and 0.5 M LiClO ₄ were dissolved in 30 ml of dehydrated methanol and injected into the cell. After removing the cell from the glove box and bubbling high-purity nitrogen for 15 minutes, constant potential electrolysis was performed at room temperature with 0.1, 0.5, 1.1 V vs. Ag / AgCl while stirring the electrolyte with a stirrer. Went for hours. 30 ml of the gas phase on the working electrode side was collected with a micro syringe (HAMILTON, 4015-42005, 1705RN, 50 ml), and the components were qualitatively and quantitatively analyzed by gas chromatography. 30 ml of the gas phase on the counter electrode side was also collected, and the components were qualitatively and quantitatively analyzed by gas chromatography. Moreover, the voltage during constant potential electrolysis was measured using an electrometer (NIKKOU KEISOKU, ELECTRO METER NE-1). The same measurement was performed for an electrolyte solution containing no ammonia borane.

The gas generated during constant potential electrolysis was qualitatively and quantitatively analyzed by gas chromatography. GC-14A (SHIMADZU) was used as the apparatus, and recording was performed with CHROMATOPAC (SHMADZU, C-R6A).
In addition, molecular sieve (GL Science, 1001-11506, 5A, 60/80 mesh) was used as a filler, argon gas was used as a carrier gas, and a thermal conductivity detector (TCD) was used as a detector.

  FIG. 7 shows the change over time in the oxidation current that flowed during constant potential electrolysis at 0.1 V in a methanol solution containing ammonia borane and a methanol solution not containing ammonia borane. When ammonia borane was not contained, the current value was almost 0, but when 10 mM ammonia borane was contained, a large current flowed immediately after application of the potential (6.8 mA), and then gradually decreased. In addition, a large amount of bubbles were generated from both the working electrode and the counter electrode.

  In order to identify the generated bubbles, qualitative and quantitative analysis was performed by gas chromatography. As a result, it was found that hydrogen was generated from both electrodes. FIG. 8 shows the change over time in the amount of hydrogen generated on the working electrode side. When ammonia borane was not contained (without AB, 0.1 V), nothing was detected by measurement for 24 hours. On the other hand, when ammonia borane was contained (10 mM AB, 0.1 V), nothing was detected immediately after bubbling nitrogen, but hydrogen was detected immediately after the potential was applied. Increased. Since hydrogen was generated even when the Pt electrode was just immersed in a methanol solution in which 10 mM ammonia borane was dissolved (10 mM AB, methanolysis), the contribution from methanol decomposition was excluded from the calculated hydrogen amount in the subsequent data. From this result, it was found that when ammonia borane was contained, the electrochemical dehydrogenation reaction of ammonia borane proceeded by applying a potential to generate hydrogen.

  FIG. 9 shows the change over time in the amount of hydrogen generated on the counter electrode side. In the counter electrode, when no ammonia borane was contained (without AB, 0.1 V), nothing was detected, but when ammonia borane was contained (10 mM AB, 0.1 V), hydrogen was detected and increased with time. . In addition, even when no potential was applied (10 mM AB, methanolysis), generation of hydrogen due to methanol decomposition of ammonia borane was observed.

  The relationship between the amount of electricity obtained and the amount of hydrogen generated on the working electrode side or the counter electrode side is shown in FIGS. In both electrodes, when the amount of electricity increases, the amount of hydrogen generated also increases. On the working electrode side, 254 mmol (0.85 equivalents) is generated at an electric amount of 50 coulomb, and 71 mmoles of hydrogen is generated at an electric amount of 48 C on the working electrode side. .

  FIG. 12 shows changes with time in current when constant potential electrolysis is performed with 0.5 V vs. Ag / AgCl in a methanol solution containing 10 mM ammonia borane. A large current of 9.2 mA flowed immediately after the potential application, but then gradually decreased. This behavior was the same as the 0.1V result.

  13 and 14 show the relationship between the amount of electricity obtained and the amount of hydrogen generated on the working electrode side or the counter electrode side in the constant potential electrolysis measurement at 0.5V. Hydrogen was detected even at this potential, and the amount of hydrogen generated increased with an increase in the amount of electricity. Further, in the constant potential electrolysis at 0.5 V, 308 mmol (1.02 equivalents) of hydrogen was obtained with an electric quantity of 43 coulombs, and more hydrogen was generated than the measurement at 0.1 V. At the counter electrode, 84 mmol of hydrogen was generated at 44 coulombs, more than the measurement at 0.1V. From this result, it is considered that the electrochemical dehydrogenation reaction of ammonia borane further proceeds by applying a larger potential.

  FIG. 15 shows changes in current during constant potential electrolysis in 1.1 V vs. Ag / AgCl. Even at this potential, a large current was obtained immediately after the start of the measurement, and thereafter, the potential decreased. However, compared with the result at 0.5 V, the current value at the initial stage was small, and the current decreased rapidly. The reason is considered to be that a factor that inhibits the dehydrogenation reaction of ammonia borane appeared by applying a potential close to the potential window on the oxidation side of methanol.

  The relationship between the amount of electricity obtained and the amount of hydrogen generated on the working electrode side or the counter electrode side is shown in FIGS. In both electrodes, the amount of hydrogen generation increased as the amount of electricity increased. However, the amount of hydrogen generated from the working electrode is 286 mmol (0.95 equivalent) with an electric amount of 49 coulombs, and the amount of hydrogen generated from the counter electrode is 75 mmol with an electric amount of 49 coulombs, which is smaller than the measurement at 0.5V. there were.

    1: Electrolyte tank 3: Electrolyte solution 5: Anode (working electrode) 6: Cathode (counter electrode) 8: Reference electrode 10: Nitrogen inlet 12: Sampling port 15: Gas outlet 16: Nitrogen outlet 20: Hydrogen production device 21: Electrolyte 23: Air electrode 24: Fuel electrode 26: Fuel cell

Claims (6)

A method for producing hydrogen, wherein hydrogen is generated by electrolyzing an electrolytic solution in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent.   The method according to claim 1, wherein the organic solvent is an alcohol. 3. The method according to claim 1, wherein the electrolytic solution has an ammonia borane concentration of 10 mmol · dm ⁻³ or more and 100 mmol · dm ⁻³ or less. An electrolyte bath for storing an electrolyte solution in which ammonia borane (NH ₃ BH ₃ ) and a supporting electrolyte are dissolved in an organic solvent, an anode, and a cathode, and by applying a voltage between the anode and the cathode, A hydrogen production apparatus for generating hydrogen from an anode or the cathode.   The apparatus according to claim 4, wherein the anode or the cathode is made of platinum, palladium, nickel, copper, or iron. A hydrogen production apparatus according to claim 4 or 5,
A power generation system comprising: a fuel cell capable of using hydrogen generated from the hydrogen production apparatus as fuel.

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