A cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst, a preparation method and application thereof

Abstract

The application discloses a cobalt phosphide / nitrogen-doped porous carbon loaded ruthenium catalyst which is composed of cobalt phosphide / nitrogen-doped porous carbon CoP-NC and Ru elements; the CoP-NC is obtained by mixing ZIF-67 and sodium hypophosphite NaH2PO2 and then performing multi-stage calcination to realize carbonization and phosphorization at the same time; the ZIF-67 is obtained by chemically synthesizing cobalt nitrate hexahydrate, dimethyl imidazole and methanol; the Ru element is obtained by reducing and loading ruthenium trichloride hydrate; the ZIF-67 is a cobalt source and a nitrogen source, the sodium hypophosphite is a phosphorus source, and the ruthenium trichloride hydrate is a ruthenium source. A preparation method of the catalyst comprises the following steps: 1, preparation of ZIF-67; 2, preparation of CoP-NC; and 3, preparation of Ru / CoP-NC. As a catalytic application in the aspect of ammonia borane hydrolysis hydrogen production, the hydrogen evolution turnover frequency is 200-400 mol H2 ·mol Ru ‑1 ·min ‑1 , the hydrolysis hydrogen release time is 20-60 s, the catalytic hydrogen release activation energy is E a = 30-40 kJ·mol ‑1 ; at the condition of 25 DEG C, after 5 cycles, 50-60% of the initial catalytic activity is kept.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalytic hydrogen production, in particular to a cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst, a preparation method and application thereof. BACKGROUND

[0002] As an important application direction of ammonia borane hydrogen production, the catalytic performance of the hydrogen production catalyst for ammonia borane hydrolysis depends mainly on the metal with catalytic activity and the carrier. The metals are mainly divided into two categories: noble metal catalysts and non-noble metal catalysts; the carrier is mainly carbon material, which is widely studied and used due to its high specific surface area and high active site.

[0003] A Ru / NC-Fe catalyst prepared by combining nitrogen-doped porous carbon material with ruthenium nanoparticles in the prior art 1 (Cui Z, Guo Y, Feng Z, et al. Ruthenium nanoparticles supported on nitrogen doped porous carbon as a highly efficient catalyst for hydrogen evolution from ammonia borane [J]. New Journal of Chemistry, 2019) can realize catalytic hydrolysis of ammonia borane to produce hydrogen, and the hydrogen evolution conversion rate at room temperature is 102.9 mol H2 ·mol Ru -1 ·min -1 . The catalytic activity of the catalyst is poor compared with similar ruthenium supported catalysts. However, the nitrogen-doped carbon material as a carrier has certain catalytic activity, which is proved in the prior art 1; in addition, the addition of ferrocene carboxyl aldehyde in the technical solution forms iron oxide, so that the catalyst has magnetic properties and is easy to recover, but the technical problem solved by this technical feature is irrelevant to the present application.

[0004] A Co / NPCNW catalyst prepared by combining nitrogen-doped porous carbon nanowires with cobalt nanoparticles in the prior art 2 (Zhou L, Jing M, Pan L, et al. Ultrasmall cobalt nanoparticles supported on nitrogen-doped porous carbon nanowires for hydrogen evolution from ammonia borane [J]. Materials Horizons, 2017) can realize catalytic hydrolysis of ammonia borane to produce hydrogen, and the hydrogen evolution conversion rate at room temperature is 7.29 mol H2·mol Co -1 ·min -1 The prior art also uses nitrogen-doped carbon material as a carrier, but its technical effect is also poor in the same type of cobalt-loaded catalyst.

[0005] According to the above prior art 1 and prior art 2, the following conclusions can be drawn in the field of metal catalysts: the catalytic performance of a single metal cannot meet the application requirements. The corresponding solution is to use a bimetallic catalyst. For example, prior art 3 (Liu Z, Yang X, Hu G, et al. Ru Nanocluster Coupled over Co / N Doped Carbon Nanotube Efficiently Catalyzed Hydrogen Evolution Reaction [J]. ACS Sustainable Chemistry & Engineering, 2020) prepared a Ru@Co / N-CNTs catalyst by loading ruthenium nanoparticles on Co / N-doped carbon nanotubes, and realized the catalytic hydrolysis of ammonia borane to produce hydrogen at room temperature, with a hydrogen evolution conversion frequency of 33.6 mol H2 ·mol Ru -1 ·min -1 The technical solution uses Co / N-doped carbon nanotubes with more active sites as a carrier to load ruthenium nanoparticles, which makes it have better dispersibility when loading cobalt nanoparticles, and at the same time realizes the synergistic effect between Ru and Co bimetallic. However, in this technical solution, due to the problem of electron transfer limitation between the carrier and the metal, the catalytic activity still cannot meet the requirements. To solve the technical problems of prior art 3, the carrier can be adjusted to improve it.

[0006] Returning to prior art 1 and prior art 2, the following conclusions can be drawn in the field of carriers: under the premise of the same type of metal catalyst, the carrier has a significant impact on the catalytic performance. In combination with prior art 3, the inventors' research group provided an integrated catalyst preparation method in the previous research work, i.e., prior art 4 (CN202210502981.4.2022 A kind of nitrogen-doped porous carbon coated embedded ruthenium cobalt phosphide composite material based on graphene oxide), which is to integrate the synthesis of ruthenium nanoparticles and organic framework during synthesis, and then perform phosphatization and carbonization. This technical feature directly leads to fewer active sites on the surface of the catalyst, thereby reducing the catalytic performance. Although this technical solution is beneficial to the uniform distribution of ruthenium nanoparticles, subsequent research has found that this technical solution has the following technical problems: due to the use of integrated synthesis method, a part of the ruthenium nanoparticles cannot be exposed, which leads to a decrease in the intrinsic activity of the catalyst.

[0007] The above technical problems can be solved by first preparing a carrier and then loading ruthenium nanoparticles, thereby increasing the exposure of ruthenium nanoparticles and ultimately improving the catalytic performance. However, the conventional method of first preparing a carrier and then loading has the problems of small loading amount and small loading range of the loaded material, so in order to solve the above problems, the inventors have found that the effect of increasing active sites can be achieved by modifying the carrier during the preparation of the carrier. SUMMARY

[0008] The purpose of the present application is to provide a cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst and its preparation method and application.

[0009] The basic principle of solving the problems of the prior art is that, during the preparation of nitrogen-doped porous carbon, ZIF-67 and sodium hypophosphite NaH2PO2 are used together for multi-stage calcination, the phosphine gas generated by sodium hypophosphite at high temperature is used to modify ZIF-67 during carbonization, so that the nitrogen-doped porous carbon has more exposed active sites when used as a carrier, thereby improving the dispersion of ruthenium nanoparticles when ruthenium nanoparticles are loaded, and ultimately improving the catalytic activity. The specific technical effects are as follows:

[0010] 1. Utilize the property of phosphine gas generated by sodium hypophosphite at high temperature to modify ZIF-67 during carbonization, thereby increasing the number of exposed active sites on the surface, so that the ruthenium nanoparticles have better dispersion when loaded with ruthenium nanoparticles, and thus the intrinsic catalytic activity is improved;

[0011] 2. The method of using ZIF-67 and sodium hypophosphite together for multi-stage calcination can make carbonization and phosphorization more thorough, thereby achieving the technical effects of increasing and adjusting active sites, and improving the intrinsic activity;

[0012] 3. The preparation method of loading ruthenium nanoparticles after phosphorizing the carrier improves the synergistic effect between cobalt and ruthenium bimetallic, thereby improving the intrinsic activity.

[0013] In order to achieve the above-mentioned purpose of the application, the technical scheme adopted by the present application is as follows:

[0014] A cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst, which is composed of cobalt phosphide / nitrogen-doped porous carbon CoP-NC and Ru elements; wherein,

[0015] The CoP-NC is obtained by mixing ZIF-67 and sodium hypophosphite NaH2PO2 and then performing multi-stage calcination to achieve carbonization and phosphorization at the same time;

[0016] The ZIF-67 is chemically synthesized by cobalt nitrate hexahydrate, dimethyl imidazole and methanol;

[0017] The Ru element is obtained by reduction of ruthenium trichloride hydrate.

[0018] The ZIF-67 is a cobalt source and a nitrogen source, sodium hypophosphite is a phosphorus source, and ruthenium trichloride hydrate is a ruthenium source; wherein the multi-stage calcination simultaneously realizes carbonization and phosphorization, that is, the doping of N elements and P elements is completed.

[0019] A preparation method of a cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst, comprising the following steps:

[0020] Step 1, preparation of ZIF-67, ultrasonic cobalt nitrate hexahydrate in methanol to obtain solution A, at the same time, dissolve dimethyl imidazole in a certain amount of methanol to obtain solution B, then, under the condition of magnetic stirring, add solution B to solution A and mix uniformly to obtain solution C, then, age the solution C, that is, the purple precipitate can be obtained, finally, the purple precipitate is centrifuged, washed and dried under certain conditions, that is, the purple precipitate, ZIF-67, is obtained;

[0021] In the step 1, the mass ratio of cobalt nitrate hexahydrate to dimethyl imidazole is 0.911:1;

[0022] The aging condition is that the aging time is 10-36h at room temperature;

[0023] The centrifugal washing and drying condition is that the washing liquid is methanol, the centrifugal speed is 8000-10000 revolutions per minute, the centrifugal time is 3-9 minutes, the washing times is 3-6 times, the drying temperature is 60-90℃, and the drying time is 10-16h;

[0024] Step 2, preparation of CoP-NC, first, mix and grind ZIF-67 obtained in step 1 with sodium hypophosphite under certain conditions to obtain mixture D, then, carry out multi-stage calcination to realize carbonization and phosphorization under certain conditions to obtain black product, finally, wash, filter and vacuum dry the black product, that is, cobalt phosphide / nitrogen-doped porous carbon, named CoP-NC, is obtained;

[0025] In the step 2, the mass ratio of ZIF-67 to sodium hypophosphite is 1:1, and the mixing and grinding time is 30-90min;

[0026] The conditions of the multi-stage calcination are that the temperature of the first stage calcination is 60-90 DEG C, the time is 3-6h, the temperature increasing rate of the second stage calcination is 5-10 DEG C / min, the temperature is 300-600 DEG C, the time is 1-3h, the temperature increasing rate of the third stage calcination is 5-10 DEG C / min, the temperature is 800-1200 DEG C, and the time is 3-6h.

[0027] Step 3, preparation of Ru / CoP-NC, first, the CoP-NC obtained in step 2 and ruthenium trichloride hydrate are placed in deionized water to obtain a mixture E, then sodium borohydride aqueous solution is added to the mixture E to carry out a reduction reaction until no bubbles are generated, finally, the obtained product is filtered, washed and dried to obtain a ruthenium loaded cobalt phosphide / nitrogen doped porous carbon, named as Ru / CoP-NC.

[0028] In the step 3, the mass ratio of CoP-NC, ruthenium trichloride hydrate and sodium borohydride is 50:3:19.

[0029] The ruthenium loaded cobalt phosphide / nitrogen doped porous carbon is used as a catalyst for hydrogen production by hydrolysis of ammonia borane, the hydrogen evolution conversion frequency is 200-400 mol H2 ·mol Ru –1 ·min –1 , the hydrolysis hydrogen release time is 20-60s, the activation energy of the catalytic hydrogen release is E a =30-40kJ·mol –1 ; at 25 DEG C, after 5 cycles, the initial catalytic activity is maintained at 50-60%.

[0030] The beneficial technical effects of the material obtained by the application can be known through the following detection:

[0031] It can be known through XRD detection that Ru / CoP-NC does not detect the characteristic peak of Ru in addition to the characteristic peaks of CoP and C, which is speculated to be caused by the low loading amount of Ru;

[0032] It can be known through SEM detection that Ru / CoP-NC presents a typical porous dodecahedron microstructure;

[0033] It can be known through EDS testing that C, N, Ru, Co and P five elements exist in Ru / CoP-NC, and the distribution position is relatively concentrated;

[0034] It can be known through hydrogen production test detection that the hydrogen evolution conversion frequency provided at 25 DEG C is 370.4 mol H2 ·mol Ru –1 ·min –1 , and the hydrolysis rate is 100%;

[0035] The reaction kinetics performance detection can know that: the apparent activation energy E of the reaction a = 37.04 kJ·mol –1 ;

[0036] The cycle performance detection can know that: 53% of the initial catalytic activity is retained after 5 cycles at 25 DEG C.

[0037] Therefore, the present application has the following advantages compared with the prior art:

[0038] 1. The present application adopts the method of ZIF-67 and sodium hypophosphite multi-stage calcination to prepare the carrier, and the multi-stage calcination method can make the carbonization and phosphatization of ZIF-67 more thorough, thereby increasing and adjusting the active sites, and further improving the uniformity and dispersity when loading the load;

[0039] 2. The present application utilizes the characteristic that sodium hypophosphite generates phosphine gas at high temperature, and modifies ZIF-67 at the same time of completing carbonization, thereby increasing the number of exposed active sites on the surface, making the ruthenium nanoparticles have better dispersity when loading the ruthenium nanoparticles, and further improving the intrinsic catalytic activity;

[0040] 3. The present application adopts the preparation method of loading ruthenium nanoparticles after phosphatization, and does not affect the normal loading of ruthenium nanoparticles while phosphatizing Co into CoP, thereby improving the synergistic effect between cobalt and ruthenium bimetal, and improving the intrinsic activity;

[0041] 4. The raw materials used in the present application all belong to the chemical raw materials that have been industrialized, and are marketable, easy to obtain, and used for simple synthesis process, short reaction period, low energy consumption and low pollution in the reaction process;

[0042] 5. As the application of catalytic hydrogen production material, the cobalt phosphide / nitrogen-doped porous carbon has high hydrogen production performance of ammonia borane hydrolysis, high hydrogen evolution conversion rate at 25 DEG C, and low reaction activation energy.

[0043] Therefore, the present application has better hydrogen production catalytic performance and material stability compared with the prior art, and has wide application prospect in the field of hydrogen production. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 The XRD pattern of ZIF-67 prepared in step 1 of example 1;

[0045] Figure 2 The SEM pattern of ZIF-67 prepared in step 1 of example 1;

[0046] Figure 3 The XRD pattern of CoP-NC prepared in step 2 of example 1;

[0047] Figure 4 SEM image of CoP-NC prepared in step 2 of Example 1;

[0048] Figure 5 Ru / CoP-NC prepared in step 3 of Example 1;

[0049] Figure 6 XRD image of Ru / CoP-NC prepared in step 3 of Example 1;

[0050] Figure 7 EDS image of Ru / CoP-NC prepared in step 3 of Example 1;

[0051] Figure 8 SEM image of Ru / CoP-NC prepared in step 3 of Example 1;

[0052] Figure 9 Ru / CoP-NC prepared in step 3 of Example 1;

[0053] Figure 10 Ru / CoP-NC prepared in step 3 of Example 1 at different temperatures;

[0054] Figure 11 Ru / Co-NC prepared in Comparative Example 1. DETAILED DESCRIPTION

[0055] The present application is further described in detail by way of examples with reference to the accompanying drawings.

[0056] Example 1

[0057] A preparation method of a cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst, comprising the following steps:

[0058] Step 1, preparation of ZIF-67, 8.732 g of cobalt nitrate hexahydrate was ultrasonically dispersed in 300 mL of methanol for 20 min to obtain solution A, at the same time, 9.583 g of dimethyl imidazole was dissolved in 100 mL of methanol to obtain solution B, then, solution B was added to solution A under magnetic stirring to obtain solution C, then, the solution C was aged at room temperature for 24 h to obtain a purple precipitate, finally, the purple precipitate was washed and centrifuged under the conditions of a washing liquid of methanol, a centrifugal speed of 8000 rpm, a centrifugal time of 5 min and 5 times of washing, and then dried at a drying temperature of 60 ℃ for 15 h to obtain the purple precipitate, i.e. ZIF-67;

[0059] In order to prove the composition of the purple precipitate obtained in step 1, XRD test was performed. The test results are shown in FIG. 2. Figure 1 As shown in FIG. 2, the characteristic peaks obtained by testing the purple precipitate are consistent with the characteristic peaks of ZIF-67. The test results show that the purple precipitate is ZIF-67, i.e. ZIF-67 is successfully prepared.

[0060] In order to prove the micro-morphology of the purple precipitate obtained in step 1, SEM test was performed. The test results are shown in FIG. 3. Figure 2 As shown in FIG. 3, the morphology of the purple precipitate is a standard dodecahedron structure.

[0061] Step 2, preparation of CoP-NC, first, the ZIF-67 obtained in step 1 and sodium hypophosphite were mixed and ground at a mass ratio of 1:1 for 1 h to obtain mixture D, then, the mixture D was subjected to multi-stage calcination under certain conditions to realize phosphorization and carbonization, thereby obtaining a black product, finally, the black product was washed, suction filtered and vacuum dried to obtain cobalt phosphide / nitrogen-doped porous carbon, named CoP-NC;

[0062] The conditions of the multi-stage calcination are as follows: the temperature of the first-stage calcination is 80 ℃, the time is 5 h, the temperature of the second-stage calcination is 300 ℃ with a heating rate of 5 ℃ / min, the time is 2 h, the temperature of the third-stage calcination is 900 ℃ with a heating rate of 5 ℃ / min, and the time is 5 h;

[0063] In order to prove the composition of the CoP-NC obtained in step 2, XRD test was performed. The test results are shown in FIG. 5. Figure 3 As shown in FIG. 5, the CoP-NC contains the characteristic peaks of CoP and C, and the characteristic peaks of the original ZIF-67 disappear. The test results show that, through multi-stage calcination, carbonization of ZIF-67 is realized at the same time as phosphorization.

[0064] The first-stage calcination realizes the drying and preheating of ZIF-67;

[0065] The role of the second-stage calcination is to realize carbonization of ZIF-67;

[0066] The role of the third-stage calcination is to realize thermal decomposition of sodium hypophosphite, and at the same time, to realize phosphorization by reacting phosphine gas generated by the decomposition with carbon material formed after carbonization of ZIF-67.

[0067] That is, the mechanism of phosphorization is that sodium hypophosphite is thermally decomposed to generate phosphine gas, which reacts with carbon material formed after carbonization of ZIF-67 to realize phosphorization.

[0068] In order to prove the micro-morphology of CoP-NC obtained in step 2, SEM test is performed. The test result is shown in FIG. 2. Figure 4 As shown in FIG. 2, CoP-NC has a porous dodecahedron microstructure. The test result shows that the multi-stage calcination process not only can maintain the original micro-morphology of ZIF-67, but also can form more pores and defects on the surface thereof on this basis.

[0069] In order to compare the catalytic performance of Ru / CoP-NC obtained in step 3, hydrolysis performance test is performed on CoP-NC obtained in step 2.

[0070] The specific test method of the hydrolysis performance test is as follows: under the conditions of standard atmospheric pressure and 25℃, 100mg of the sample to be tested is placed in a wide-mouth bottle, 20mL of deionized water is added to fully stir and disperse, then the wide-mouth bottle is connected to a measuring tube filled with water in a constant-temperature water bath under the condition of magnetic stirring, 10mL of 0.1mmol / mL ammonia borane aqueous solution is injected, finally, the volume of hydrogen generated is calculated by the drainage method; wherein, the hydrogen evolution conversion frequency is calculated by the hydrogen evolution time, which can reflect the reaction rate of hydrolysis hydrogen evolution.

[0071] The hydrolysis performance test result of CoP-NC is shown in FIG. 3. Figure 5 As shown in FIG. 3, the amount of hydrogen released is less than 5mL after 500s of catalytic time. The test result shows that the catalytic performance of CoP-NC can be ignored.

[0072] Step 3, preparation of Ru / CoP-NC, with the mass ratio of CoP-NC obtained in step 2, ruthenium trichloride hydrate and sodium borohydride being 3:19, first, 100mg of CoP-NC and 6mg of ruthenium trichloride hydrate are stirred in deionized water for 6h to obtain a mixture E, then 38mg of sodium borohydride in water is added to the mixture E to perform a reduction reaction until no bubbles are generated, finally, the obtained product is filtered, washed and dried to obtain ruthenium-loaded cobalt phosphide / nitrogen-doped porous carbon, which is named as Ru / CoP-NC.

[0073] To prove the composition of Ru / CoP-NC obtained in step 3, XRD test was performed. The test results are shown in Figure 6 As shown, the characteristic peaks of Ru / CoP-NC have no obvious difference with those of CoP-NC, i.e. no characteristic peaks of Ru are detected, which is because the content of Ru element is lower than the detection threshold.

[0074] Therefore, in order to further prove the successful loading of Ru, EDS test was performed. The test results are shown in Figure 7 As shown, Ru / CoP-NC contains N element, Co element, P element and C element of CoP-NC, and Ru element, i.e. it proves the successful loading of Ru.

[0075] To prove the micro-morphology of Ru / CoP-NC obtained in step 3, SEM test was performed. The test results are shown in Figure 8 As shown, Ru / CoP-NC still maintains the same porous dodecahedron structure as CoP-NC. In combination with the XRD test results, it can be known that the process of loading Ru does not change the micro-morphology of the material.

[0076] To prove that Ru / CoP-NC has the performance as a catalyst for hydrogen production by hydrolysis of ammonia borane, hydrolysis performance test was performed. The test results are shown in Figure 5 As shown, the hydrogen release time is 32 s, the hydrogen evolution turnover frequency is 370.4 mol H2 ·mol Ru –1 ·min –1 , and the hydrolysis rate is 100%.

[0077] By comparing CoP-NC and Ru / CoP-NC, it can be known that the loading of Ru can greatly reduce the hydrogen release time, i.e. significantly improve the hydrogen release rate; at the same time, the hydrolysis rate is significantly improved, from 7% to 100%.

[0078] To prove the cycle performance of Ru / CoP-NC, cycle performance test was performed. The specific test method is: repeating the injection of aqueous solution of ammonia borane to perform hydrolysis performance test, i.e. cycle performance test can be realized. The cycle performance test results of Ru / CoP-NC are shown in Figure 9 As shown, after 5 cycles, the hydrogen evolution turnover frequency is 196.91 mol H2 ·mol Ru –1 ·min –1 , and the hydrolysis rate is 100%. The test results show that Ru / CoP-NC has cycle performance.

[0079] To prove the effect of Ru / CoP-NC on the kinetics of ammonia borane hydrolysis, the hydrolysis performance test was carried out at different temperatures, and the test temperatures were 25℃, 35℃, 45℃ and 55℃ respectively. The test results are shown in Figure 10 and Table 1, the activation energy calculated by Arrhenius equation fitting is 37.04kJ·mol –1 , which proves that Ru / CoP-NC significantly improves the kinetics of ammonia borane hydrolysis.

[0080] Table 1 Hydrogen evolution turnover frequency and time required for complete hydrolysis of ammonia borane at different temperatures

[0081] Temperature (°C) 25 35 45 55 Time (s) required to complete the hydrolysis of hydrogen 32 15 9 8 (mol H2 • mol Ru –1 • min –1 )]]> 370.4 763.6 1257.3 1425.1

[0082] To prove the effect of phosphating in step 2 on the performance, Comparative Example 1 is provided, which is Ru / Co-NC obtained without phosphating operation.

[0083] Comparative Example 1

[0084] A method for preparing Ru / Co-NC, the steps not specifically described are the same as those in Example 1, the difference is that when performing the step 2, the ZIF-67 obtained in step 1 is directly calcined alone, that is, no sodium hypophosphite is added for calcination, and the obtained material is named as Ru / Co-NC.

[0085] The hydrolysis performance test results of Ru / Co-NC are shown in Figure 11 , the hydrogen evolution time is 143s, the hydrogen evolution turnover frequency is 86.15mol H2 ·mol Ru –1 ·min –1 , and the hydrolysis rate is 100%.

[0086] By comparing Example 1 and Comparative Example 1, it can be seen that phosphating can significantly reduce the hydrogen evolution time and improve the hydrogen evolution turnover frequency, and the effect reaches 4.5 times.

[0087] The above comparison can prove that phosphating can significantly improve the catalytic activity by significantly improving the speed of electron transfer.

Claims

1. Use of a cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst for hydrogen production from ammonia borane hydrolysis, characterized in that: The phosphorus cobalt / nitrogen-doped porous carbon supported ruthenium catalyst is composed of CoP-NC and Ru elements; The preparation method of the phosphorus cobalt / nitrogen-doped porous carbon supported ruthenium catalyst comprises the following steps: Step 1, preparation of ZIF-67, the cobalt nitrate hexahydrate is ultrasonically treated in methanol to obtain solution A, at the same time, the dimethyl imidazole is dissolved in a certain amount of methanol to obtain solution B, then, under the condition of magnetic stirring, the solution B is added to the solution A and mixed uniformly to obtain solution C, then, the solution C is aged to obtain purple precipitate, finally, the purple precipitate is centrifuged, washed and dried under certain conditions to obtain the purple precipitate, namely ZIF-67; In the step 1, the mass ratio of the cobalt nitrate hexahydrate and the dimethyl imidazole is 0.911:1; The aging condition is that the aging time is 10-36 h at room temperature; The centrifugal washing and drying condition is that the washing liquid is methanol, the centrifugal speed is 8000-10000 rpm, the centrifugal time is 3-9 min, the washing times is 3-6 times, the drying temperature is 60-90 DEG C, and the drying time is 10-16 h; Step 2, preparation of CoP-NC, first, the ZIF-67 obtained in the step 1 is mixed and ground with sodium hypophosphite under certain conditions to obtain mixture D, then, the mixture D is subjected to multi-stage calcination for carbonization and phosphorization to obtain black product, finally, the black product is washed, suction filtered and vacuum dried to obtain the phosphorus cobalt / nitrogen-doped porous carbon, which is named as CoP-NC; In the step 2, the mass ratio of the ZIF-67 and the sodium hypophosphite is 1:1, and the mixing and grinding time is 30-90 min; In the step 2, the multi-stage calcination condition is that the first-stage calcination temperature is 60-90 DEG C, the time is 3-6 h, the second-stage calcination temperature increasing rate is 5-10 DEG C / min, the temperature is 300-600 DEG C, and the time is 1-3 h, the third-stage calcination temperature increasing rate is 5-10 DEG C / min, the temperature is 800-1200 DEG C, and the time is 3-6 h; Step 3, preparation of Ru / CoP-NC, first, the CoP-NC obtained in the step 2 and ruthenium trichloride hydrate are placed in deionized water to obtain mixture E, then, the aqueous solution of sodium borohydride is added to the mixture E to carry out reduction reaction until no gas bubble is generated, finally, the obtained product is suction filtered, washed and dried to obtain the phosphorus cobalt / nitrogen-doped porous carbon supported ruthenium catalyst, which is named as Ru / CoP-NC; In the step 3, the mass ratio of the CoP-NC, the ruthenium trichloride hydrate and the sodium borohydride is 50:3:

19.

2. Use of the cobalt phosphide / nitrogen-doped porous carbon supported ruthenium catalyst according to claim 1 for the hydrogen production by ammonia borane hydrolysis, characterized in that: hydrogen evolution turnover frequency of 200-400 mol H2 ·mol Ru –1 ·min –1 hydrolytic hydrogen evolution time of 20-60 s, and a catalytic hydrogen evolution activation energy of E a = 30-40 kJ·mol –1 ; at 25 °C, 50-60% of the initial catalytic activity is maintained after 5 cycles.

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