An efficient hydrogen storage material platinum-carbon catalyst, its preparation method and application

Abstract

The present invention provides an efficient hydrogen storage platinum-carbon catalyst, its preparation method and application, belonging to the technical field of electrolytic hydrogen production. The preparation method includes the following steps: First, a mixed solution containing 0.1-1 g of carbon carrier, 2-5000 mg of heteropolyacid as a platinum complex ligand, 0.05-5 mg of chloroplatinic acid and 2-25 ml of organic solvent is ultrasonically treated at room temperature for 0.5-4 h. Then, after the mixture is completely dried at 50-90 °C, it is calcined in a hydrogen atmosphere at 300-600 °C for 2-4 h to obtain a carbon-supported Pt catalyst. This preparation method is simple. The prepared platinum-carbon catalyst has a low Pt content and good catalytic performance, and the mass activity can be as high as 32.8 A / mg Pt, which is 2-3 times the best reported platinum catalyst activity at present.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production by electrolysis, and more specifically, to a high-efficiency hydrogen storage platinum-carbon catalyst, a preparation method thereof, and an application thereof. Background Art

[0002] With the continuous growth of the world's population and economy, the demand for energy is also increasing continuously. Hydrogen is considered the cleanest energy source because the combustion of hydrogen releases energy and only produces by-product water. The weight density of hydrogen energy is usually about 7 times higher than that of fossil fuels. Currently, hydrogen is obtained from various sources, including fossil fuels, biomass, and water electrolysis. Hydrogen has great potential and has been used in industry, transportation, and energy production. Without a doubt, hydrogen energy will be one of the main energy sources in the future.

[0003] Hydrogen energy storage is an essential part of the hydrogen economy. Liquid-phase chemical hydrides have been widely developed for hydrogen storage due to their high capacity, mild dehydrogenation conditions, and good stability at room temperature. Several promising liquid-phase hydrogen storage materials, such as formic acid, ammonia borane, hydrazine hydrate, and aromatic compounds, have received great attention in hydrogen storage. Formic acid and methanol are organic small molecules with wide sources, and hydrogen accounts for 4.4% and 12.3% of their mass fractions respectively. Their stable properties make them good hydrogen storage materials with low transportation risks.

[0004] The hydrogen production by formic acid oxidation has received great interest from researchers, and many catalysts for hydrogen production by formic acid electrolysis have been developed. Li et al. reported a ternary CoPtAu nanoparticle catalyst system for formic acid oxidation, with a mass activity of 11.97 A / mgPt. Single-atom Rh anchored on N-doped carbon shows unexpected catalytic performance for formic acid oxidation, and a mass activity of up to 16.1 A / mg Pt can be achieved at the peak potential. An ultrasonic-assisted method was developed to enable Pt and Au to be uniformly and densely loaded on carbon black without any surfactant. The Pt-Au / C sample with a Pt / Au atomic ratio of 32:68 shows a high catalytic activity of 14.5 A / mgPt. As reported in the literature, Pt is one of the most effective electrocatalysts for hydrogen production by formic acid oxidation.

[0005] Metal platinum catalysts are the most common catalysts for the electrocatalytic oxidation of formic acid to hydrogen, but in current research, they have the following disadvantages:

[0006] (1) Metal platinum is a common precious metal, and its price is expensive. The reported platinum usage in catalysts is very high, resulting in high catalyst costs.

[0007] (2) Side reactions occur in the formic acid oxidation to hydrogen reaction, that is, the products are carbon monoxide and water. Metal platinum is prone to combine with carbon monoxide, resulting in poisoning of the platinum catalyst.

[0008] (3) Alloys of platinum and other metals are common catalysts for hydrogen production from formic acid. Although the alloy can reduce platinum poisoning, the synthesis steps of the catalyst are relatively complex.

[0009] Therefore, it is necessary to design and develop a highly efficient hydrogen storage platinum-carbon catalyst, its preparation method and hydrogen production catalytic system. Summary of the Invention

[0010] Based on the above technical problems existing in the prior art, the purpose of the present invention is to provide a highly efficient hydrogen storage platinum-carbon catalyst, its preparation method and application. The preparation method is simple, the prepared platinum-carbon catalyst has a low Pt content, good catalytic performance and low cost.

[0011] To achieve the above purpose, the technical solution of the present invention is as follows:

[0012] A preparation method of a highly efficient hydrogen storage platinum-carbon catalyst, comprising the following steps:

[0013] First, a mixed solution containing 0.1-1 g of carbon support, 2-5000 mg of heteropolyacid as a platinum complex ligand, 0.05-5 mg of chloroplatinic acid and 2-25 ml of organic solvent is ultrasonically treated at room temperature for 0.5-4 h, and then the mixture is completely dried at 50-90 °C and calcined in a hydrogen atmosphere at 300-600 °C for 2-4 h to obtain a carbon-supported Pt catalyst (platinum-carbon catalyst).

[0014] Further, the carbon support includes any one of activated carbon AC, acetylene black AB, carbon nanotube CNT, carbon black KJC or supercapacitor carbon SEAC.

[0015] Further, the heteropolyacid is phosphomolybdic acid H3PMo 12 O 40 , silicomolybdic acid H4SiMo 12 O 40 , silicotungstic acid H4SiW 12 O 40 , phosphotungstic acid H3PW 12 O 40 , phosphomolybdovanadic acid (H4PMo 11 VO 40 , H5PMo 10 V2O 40 or H6PMo9V3O 40 ) any one or more of them.

[0016] Further, the organic solvent includes any one of acetone, tetrahydrofuran, dioxane, absolute ethanol, isopropanol, methyl ethyl ketone, acetylacetone.

[0017] The present invention also provides a highly efficient hydrogen storage platinum-carbon catalyst prepared by the preparation method of the above-mentioned highly efficient hydrogen storage platinum-carbon catalyst, and the Pt content in the catalyst is 0.1% to 5%.

[0018] Furthermore, the present invention also provides a redox flow electrolysis hydrogen production system, which includes: a proton exchange membrane (5), a cathode electrode (8), a cathode liquid storage tank (1), an anode electrode (7) and an anode liquid storage tank (2), which are pressed into a whole by an end plate (6); wherein, the anode liquid storage tank (2) stores a redox fluid, formic acid or methanol, and the above-mentioned highly efficient hydrogen storage platinum-carbon catalyst.

[0019] Furthermore, the cathode liquid storage tank (1) stores an acidic electrolyte solution, and the acidic electrolyte is any one of sulfuric acid, phosphoric acid, perchloric acid, and trifluoromethanesulfonic acid, with a concentration of 0.5 - 3 mol / L.

[0020] Furthermore, the content of the highly efficient hydrogen storage platinum-carbon catalyst is 0.1 - 3 g / L.

[0021] Furthermore, the redox fluid is phosphomolybdic acid H3PMo 12 O 40 、silicomolybdic acid H4SiMo 12 O 40 、silicotungstic acid H4SiW 12 O 40 、phosphotungstic acid H3PW 12 O 40 、phosphomolybdovanadic acid (H4PMo 11 VO 40 、H5PMo 10 V2O 40 or H6PMo9V3O 40 ) Any one or more of the aqueous solutions thereof, with a concentration of 0.005 - 0.1 mol / L.

[0022] Furthermore, the concentration of the formic acid or methanol is 0.1 - 3 mol / L.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] The preparation method provided by the present invention has simple steps, and the Pt loading in the obtained platinum-carbon catalyst is low, with a minimum of only 0.1%, which is suitable for methanol and formic acid oxidation.

[0025] The platinum-carbon catalyst provided by the present invention exhibits excellent catalytic performance in redox flow electrolysis hydrogen production. The mass activity of the best catalyst can be as high as 32.8 A / mg Pt, which is 2 - 3 times the activity of the best reported platinum catalyst currently. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 SEM images of Pt catalysts with different carbon loadings;

[0027] Among them, a and b are Pt / AC catalysts, c and d are Pt / AB catalysts, e and f are Pt / CNT catalysts, g and h are Pt / KJC catalysts, and i and j are Pt / SEAC catalysts.

[0028] Figure 2 Schematic diagram of the structure of a redox flow electrolysis hydrogen production system;

[0029] Among them, 1 is the cathode liquid storage tank, 2 is the anode liquid storage tank, 3 is the infusion pipeline, 4 is the pump, 5 is the proton exchange membrane, 6 is the end plate, 7 is the anode electrode, 8 is the cathode electrode, and 9 is the power supply.

[0030] Figure 3 Catalytic performance results of the platinum-carbon catalyst prepared in the examples;

[0031] Among them, a represents the linear sweep voltammetry curve (with IR compensation) of 0.1 mol l -1 PMo 12 、3 mol l -1 formic acid solution catalyzed by 485 - 0.1% Pt / SEAC at different times; b represents the polarization curve of 0.1 mol l -1 PMo 12 、3 mol l -1 formic acid solution catalyzed by 485 - 0.1% Pt / SEAC after different times; c represents different times, and the potential-time curve applied during the constant current electrolysis (100 mA cm -1 PMo 12 、3 mol l -1 formic acid solution catalyzed by 485 - 0.1% Pt / SEAC (100 mA cm -2 , the total electrode area is 20 cm 2 ); d represents the Faraday efficiency of hydrogen production. Detailed implementation manners

[0032] Many specific details are set forth in the following description in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific implementations disclosed below.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention. It should be noted that the reagents used in this embodiment are all ordinary commercially available products.

[0034] Example 1

[0035] For the Pt / C catalysts prepared with different carbon carriers, the preparation method steps are as follows:

[0036] A mixed solution containing 0.2 g of carbon carrier, 20 mg of phosphomolybdic acid (H3PMo 12 O 40 ), 0.53 mg of chloroplatinic acid and 8 ml of acetone was sonicated at room temperature for 1 h, and then the mixture was dried at 70 °C. After complete drying, it was calcined at 400 °C for 1 h in a hydrogen atmosphere to obtain Pt catalysts with different carbon loadings. The heating rate of the tubular furnace was 10 °C / min. The Pt loading was 0.1 wt.%. Among them, the selected carbon carriers were five types: activated carbon AC, acetylene black AB, carbon nanotubes CNT, Ketjen black KJC, and supercapacitor carbon SEAC. The surface structure of the obtained catalyst is as Figure 1 shown. The metal platinum on the synthesized catalyst was well dispersed, there was no obvious agglomeration of platinum particles, and the size of the obtained platinum nanoparticles was about 5 nm.

[0037] Example 2

[0038] First, a mixed solution containing 0.1 g of carbon carrier, 5000 mg of heteropolyacid as a platinum complex ligand, 5 mg of chloroplatinic acid and 25 ml of organic solvent was sonicated at room temperature for 4 h, and then the mixture was completely dried at 50 - 90 °C. After that, it was calcined at 600 °C for 4 h in a hydrogen atmosphere to obtain a carbon-supported Pt catalyst with a Pt loading of 5 wt.%. The surface structure of its catalyst was the same as that in Example 1.

[0039] Example 3

[0040] A redox flow electrolytic hydrogen production system, as Figure 2 shown, which includes: a cathode storage tank 1, an anode storage tank 2, a liquid delivery pipeline 3, a pump 4, a proton exchange membrane 5, an anode electrode 7, a cathode electrode 8, and a power source 9. The proton exchange membrane 5, the anode electrode 7, and the cathode electrode 8 are pressed into a whole by an end plate 6; among them, the anode storage tank 2 stores the redox fluid, formic acid, and the Pt / C catalyst prepared in the above examples.

[0041] Among them, the cathode liquid storage tank 1 stores an acidic electrolyte solution, and the acidic electrolyte is any one of sulfuric acid, phosphoric acid, perchloric acid, and trifluoromethanesulfonic acid, with a concentration of 0.5 - 3 mol / L.

[0042] Among them, the redox fluid is phosphomolybdic acid H3PMo 12 O 40 、silicomolybdic acid H4SiMo 12 O 40 、silicotungstic acid H4SiW 12 O 40 、phosphotungstic acid H3PW 12 O 40 、phosphomolybdovanadic acid (H4PMo 11 VO 40 、H5PMo 10 V2O 40 or H6PMo9V3O 40 ) and any one or more of their aqueous solutions.

[0043] Example 4

[0044] This example verifies the effect of different calcination temperatures on the platinum-carbon catalyst.

[0045] The preparation method of the platinum-carbon catalyst is the same as that in Example 1. Using a tubular furnace, different calcination temperatures of 230 °C, 315 °C, 400 °C, 485 °C, and 570 °C were selected to synthesize the Pt / SEAC catalyst.

[0046] The catalytic performance of the Pt / SEAC catalyst for formic acid oxidation was measured using the redox fluid electrolytic hydrogen production system of Example 3: 50 mg of the catalyst and phosphomolybdic acid (H3PMo 12 O 40 ) solution were heated to the target temperature under stirring to be uniformly dispersed as the redox fluid and added to the anode liquid storage tank 2, and then 1.4 g of formic acid was added for the catalytic experiment. Every once in a while, some samples were taken from the anode liquid storage tank 2 and diluted to 1 mmol l -1 , and used to measure the absorbance of the solution at 700 nm, and converted to the equivalent current generated per unit mass of platinum to calculate the mass activity. The reaction conditions were: 0.054 mol / l PMo 12, 3 mol / l formic acid, 50 mg catalyst, 80 °C. The mass activities are as follows: the sample calcined at 230 °C is 7888 mA / mg Pt, the sample calcined at 315 °C is 8798 mA / mg Pt, the sample calcined at 400 °C is 14862 mA / mg Pt, the sample calcined at 485 °C is 17090 mA / mg Pt, and the sample calcined at 570 °C is 7772 mA / mg Pt. It can be seen from the results that the catalyst calcined at 485 °C has the best catalytic effect, and the catalytic activity can reach 17090 mA / mg Pt, which is 17 A / mg Pt.

[0047] Example 5

[0048] This example verified the oxidation performance of the platinum-carbon catalyst for different organic substrates, taking 485-Pt / SEAC as an example.

[0049] Take 50 mg of the 485 °C-Pt / SEAC catalyst, 0.1 mol l -1 PMo 12 , respectively take 3 mol l -1 formic acid, methanol or ethanol solution, and carry out the oxidation reaction of the organic substrate according to the method in Example 4. The reaction temperature is 100 °C, and the reaction time is 90 minutes respectively. The catalytic activity is measured. The results are 17090 mA / mg Pt for formic acid, 297 mA / mg Pt for methanol, and 882 mA / mg Pt for ethanol. It can be seen from the results that the oxidation activity order of the catalyst system for different organic hydrogen storage materials is formic acid > ethanol > methanol. Although the catalytic activity of methanol is the lowest, compared with the literature results under the same conditions, the catalytic activity of methanol is still good, and methanol can finally oxidize to CO2 and release all the electrons of the hydrogen storage material. Therefore, methanol is still one of the better hydrogen storage materials in this catalytic system.

[0050] Example 6

[0051] Performance test of the platinum-carbon catalyst for the decomposition reaction of formic acid at different formic acid concentrations.

[0052] Take the 485 °C-Pt / SEAC catalyst (hereinafter referred to as 485-Pt / SEAC) for screening different formic acid concentrations. The test method is the same as that in Example 4. The reaction conditions are: 0.054 mol / l PMo 12 , 3 mol / l, 4.5 mol / l, 6 mol / l formic acid, 50 mg catalyst, 80 °C. The mass activities are as follows: 17050 mA / mg Pt at a formic acid concentration of 3 mol / l, 16554 mA / mg Pt at a formic acid concentration of 4.5 mol / l, and 19001 mA / mg Pt at a formic acid concentration of 6 mol / l. It can be seen from the experimental results that for the oxidation performance of formic acid, the higher the formic acid concentration, the better.

[0053] Example 7

[0054] Performance test of platinum-carbon catalyst for formic acid decomposition reaction at different reaction temperatures.

[0055] The 485℃-Pt / SEAC catalyst was used for screening at different reaction temperatures, and the test method was the same as that in Example 4. The reaction conditions were: 0.054 mol / l PMo 12 , 3 mol / l formic acid, 50 mg catalyst, and the reaction temperatures were 80℃ and 100℃. The mass activities were: 17090 mA / mg Pt at 80℃ and 32817 mA / mg Pt at 100℃. It can be seen from the results that the decomposition performance of formic acid is excellent at 80℃ and 100℃, and the activity at 100℃ is higher than that at 80℃.

[0056] Example 8

[0057] This example verified the performance test of platinum-carbon catalyst for formic acid decomposition reaction at different redox fluid concentrations, taking 485-Pt / SEAC as an example.

[0058] The 485-Pt / SEAC catalyst was used for screening at different redox fluid concentrations, and the test method was the same as that in Example 4. The reaction conditions were: 0.005, 0.015, 0.025, 0.04, 0.054, 0.075, and 0.1 mol / l phosphomolybdic acid (PMo 12 ) as the redox fluid, 3 mol / l formic acid, 50 mg catalyst, and 80℃. The mass activities were: 12269 mA / mgPt at 0.005 mol / l PMo 12 , 18505 mA / mg Pt at 0.015 mol / l PMo 12 , 19564 mA / mg Pt at 0.025 mol / l PMo 12 , 20602 mA / mg Pt at 0.04 mol / lPMo 12 , 17090 mA / mg Pt at 0.054 mol / l PMo 12 , 13521 mA / mg Pt at 0.075 mol / l PMo 12 , 11906 mA / mg Pt at 0.01 mol / l PMo 12 . It can be seen from the results that the optimal redox fluid concentration is 0.04 mol / l PMo 12 .

[0059] Example 9

[0060] This example verified the performance test of platinum-carbon catalyst for formic acid decomposition reaction with different types of redox fluids, taking 485-Pt / SEAC as an example.

[0061] The 485℃-Pt / SEAC catalyst was used to screen different redox fluids. The reaction conditions were as follows: 0.1 mol / l phosphomolybdic acid (PMo 12 ), silicomolybdic acid H4SiMo 12 O 40 , silicotungstic acid H4SiW 12 O 40 , phosphotungstic acid H3PW 12 O 40 , phosphomolybdovanadic acid H4PMo 11 VO 40 aqueous solutions were used as redox fluids, 3 mol / l formic acid, 50 mg catalyst, 80℃. The mass activities were as follows: PMo 12 11906 mA / mgPt, silicomolybdic acid 14112 mA / mg Pt, silicotungstic acid 7551 mA / mgPt, phosphotungstic acid 8731 mA / mg Pt, phosphomolybdovanadic acid 17331 mA / mg Pt. From the results, it can be seen that the formic acid oxidation activity of the redox fluids containing molybdenum and vanadium is relatively high, while that of silicotungstic acid and phosphotungstic acid is relatively low. This is because the redox fluids containing tungsten have relatively weak oxidizing properties. However, due to the relatively low electrode potential of the tungsten-containing redox fluids after reduction, they can also be preferably used in the subsequent electrolytic hydrogen evolution reaction.

[0062] Example 10

[0063] This example verified the hydrogen production performance of the platinum-carbon catalyst in the redox fluid electrolysis reaction, taking 485-Pt / SEAC as an example.

[0064] 50 mg of the 485-Pt / SEAC catalyst was taken, 0.1 mol l -1 PMo 12 , 3 mol l -1 formic acid solution. The oxidation reaction of formic acid was carried out as in the method of Example 4. After the reaction time of 30, 90, and 180 minutes respectively, the solution was introduced into the anode of the electrolytic cell, and the cathode was 1 mol / l phosphoric acid. Its voltage linear sweep diagram, voltage and working current diagram, voltage and working time, and Faraday efficiency (all exceeding 90%) are as Figure 3 shown. From the results, it can be seen that the longer the reaction time, the greater the current obtained at the same voltage in its voltage linear sweep diagram, and the better the hydrogen evolution performance; the working current corresponding to the same voltage in the voltage and working current diagram is also greater; the working time with the voltage up to 1.2 V is also longer, and the more hydrogen is produced.

[0065] Comparative Example 1

[0066] A platinum-carbon catalyst was synthesized by referring to the method described in Patent CN1624963A:

[0067] 10 g of carbon black support was pretreated by reacting with 300 ml of a mixed solution of nitric acid and sulfuric acid with concentrations of 1 mol / l and 0.5 mol / l respectively at 70 °C for 2 hours, and then washed and dried. 2 g or more of the prepared carbon black was suspended in 150 ml of secondary distilled water, 1.0 g of chloroplatinic acid and 50 ml of a 1.0% concentration of silicomolybdic acid solution were added as promoters and stirred for 1 hour. Then, under the condition of constant temperature stirring, 0.1 mol / l of KOH solution was added dropwise until the pH value reached 7.0. 1 ml of a 0.1 mol / l solution of potassium sodium tartrate was added, and after stirring evenly, 20 ml of a 37% concentration of formaldehyde solution was added dropwise. The reaction was carried out at a constant temperature of 80 °C for 3 hours, washed with deionized water, filtered until no chloride ions were detected, and the filter cake was dried at 80 °C for 24 hours. Then, it was treated in a hydrogen atmosphere at 300 °C for 30 minutes to obtain a catalyst containing heteropolyacid, and the platinum content was 20%.

[0068] The prepared control platinum catalyst sample was tested for the catalytic oxidation performance of formic acid in 10 ml of a 0.054 mol / l phosphomolybdic acid solution according to the method described in Example 4, and the result was 1012 mA / gPt. The catalyst with a platinum loading of 0.1% synthesized at a calcination temperature of 485 °C in this patent has a mass activity of 17090 mA / mg Pt, which is significantly higher than the performance of the catalyst prepared by the literature control method.

[0069] The above embodiments only represent several implementation modes of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent shall be subject to the appended claims.

Claims

1. A preparation method of a high-efficiency hydrogen storage platinum-carbon catalyst, characterized in that, It includes the following steps: First, a mixed solution containing 0.1 - 1 g of carbon support, 2 - 5000 mg of heteropolyacid as a platinum complex ligand, 0.05 - 5 mg of chloroplatinic acid, and 2 - 25 ml of organic solvent is ultrasonically treated at room temperature for 0.5 - 4 h. Then, the mixture is completely dried at 50 - 90 °C and calcined in a hydrogen atmosphere at 400 - 485 °C for 2 - 4 h to obtain a carbon-supported Pt catalyst; the Pt content in the catalyst is 0.1 wt% - 5 wt%; the catalyst is used for the catalytic oxidation of organic hydrogen storage materials.

2. The preparation method according to claim 1, wherein The carbon support includes any one of activated carbon AC, acetylene black AB, carbon nanotube CNT, carbon black KJC, or super-electric carbon SEAC.

3. The preparation method according to claim 1, characterized in that, The heteropolyacid is any one or more of phosphomolybdic acid, silicomolybdic acid, silicotungstic acid, phosphotungstic acid, and phosphomolybdovanadic acid.

4. The preparation method according to claim 1, characterized in that, The organic solvent includes any one of acetone, tetrahydrofuran, dioxane, absolute ethanol, isopropanol, methyl ethyl ketone, and acetylacetone.

5. The high-efficiency hydrogen storage platinum-carbon catalyst prepared by the preparation method of the high-efficiency hydrogen storage platinum-carbon catalyst according to any one of claims 1 - 4.

6. A redox flow electrolysis hydrogen production system, characterized in that, It includes: protons An ion exchange membrane (5), a cathode electrode (8), a cathode liquid storage tank (1), an anode electrode (7), and an anode liquid storage tank (2), which are pressed into a whole by an end plate (6); wherein, the anode liquid storage tank (2) stores a redox fluid, formic acid or methanol, and the high-efficiency hydrogen storage platinum-carbon catalyst according to claim 5.

7. The redox flow electrolysis hydrogen production system according to claim 6, wherein The cathode liquid storage tank (1) stores an acidic electrolyte solution, and the acidic electrolyte is any one of sulfuric acid, phosphoric acid, perchloric acid, and trifluoromethanesulfonic acid, with a concentration of 0.5 - 3 mol / L.

8. The redox flow electrolysis hydrogen production system according to claim 6, characterized in that, The content of the high-efficiency hydrogen storage platinum-carbon catalyst is 0.1 - 3 g / L.

9. The redox flow electrolysis hydrogen production system according to claim 6, wherein, The redox fluid is an aqueous solution of any one or more of phosphomolybdic acid, silicomolybdic acid, silicotungstic acid, phosphotungstic acid, and phosphomolybdovanadic acid, with a concentration of 0.005 - 0.1 mol / L.

10. The redox flow electrolysis hydrogen production system according to claim 6, wherein, The concentration of the formic acid or methanol is 0.1 - 3 mol / L.

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