Method for hydrogen production from sodium formate by transition metal ion assisted pd / cns nanocatalyst

Abstract

The application provides a method for hydrogen production by sodium formate catalyzed by a transition metal ion assisted Pd / CNS nano-catalyst, a porous carbon nanosphere precursor is prepared by a one-pot method, and then the porous carbon nanosphere is obtained by high-temperature calcination, and then a reducing agent, sodium borohydride, is used to reduce Pd in situ 2+ Metal ions, a porous carbon nanosphere loaded metal Pd nano-catalyst is prepared, and is applied to catalyze sodium formate (NaCOOH) hydrolysis to produce hydrogen under different transition metal ion assisted conditions, and the gas conversion frequency value (TOF) in the catalysis of formic acid (NaCOOH) hydrolysis to produce hydrogen reaches 1913.2 (mol(H2+CO2)·mol Pd ‑1 ·h ‑1 ). The nano-catalyst obtained by the technical scheme has the advantages of simple production process, low preparation reaction condition requirement and excellent catalytic activity for sodium formate.

Description

TECHNICAL FIELD

[0001] The application relates to a method for preparing hydrogen by catalyzing sodium formate with a Pd / CNS nano-catalyst assisted by different transition metal ions and belongs to the field of energy materials. BACKGROUND

[0002] Hydrogen storage materials are one of the most promising processes for producing pure H2 under atmospheric conditions due to their superior hydrogen density, moderate and safe reaction conditions, excellent storage and transportation capabilities, and non-flammable and non-toxic characteristics. Therefore, hydrogen is widely considered as a clean and renewable energy carrier due to its ultra-high energy density and zero pollution, and is the most promising traditional fossil fuel alternative in future energy supply.

[0003] Sodium formate is a main raw material for producing formic acid, oxalic acid and safety powder, and the application provides a method for preparing hydrogen by catalyzing sodium formate with a Pd / CNS nano-catalyst assisted by different transition metal ions. The Pd / CNS is used as a catalyst, and can efficiently catalyze the decomposition of sodium formate to prepare hydrogen under the action of different transition metal ions. SUMMARY

[0004] In view of the above technical problems, the application provides a method for preparing hydrogen by catalyzing sodium formate under the action of a Pd / CNS nano-catalyst assisted by different transition metal ions.

[0005] In order to achieve the above purpose, the application adopts the following specific technical scheme:

[0006] The method for preparing hydrogen by catalyzing sodium formate with a Pd / CNS nano-catalyst assisted by transition metal ions comprises the following steps: loading metal Pd nano-particles on a porous carbon material carrier to obtain a Pd / C catalyst, and then catalyzing the decomposition of sodium formate to prepare hydrogen in the presence of transition metal ions.

[0007] The transition metal ions include any one of Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ and Cu 2+ .

[0008] The concentration of the sodium formate solution is 0.5-2.0 mmol / mL.

[0009] The amount of the Pd / CNS nano-catalyst is 2% mmol.

[0010] Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ and Cu 2+The ion concentration of any one of Fe, Co, Ni, Zn, Cu is any one of 0.1 mmoL / mL-3.0 mmoL / mL.

[0011] As a preferred solution, the concentration of sodium formate solution is 1.0 mmoL / mL;

[0012] Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ , Cu 2+ The ion concentration of any one of Fe, Co, Ni, Zn, Cu is any one of 0.5 mmoL / mL, 1.0 mmoL / mL, 1.5 mmoL / mL, 2.0 mmoL / mL.

[0013] The preparation method of the Pd / CNS nano-catalyst is as follows:

[0014] Step 1: Dissolve an appropriate amount of dopamine hydrochloride solid in a mixed solution of ethanol and deionized water, and stir thoroughly until completely dissolved;

[0015] Step 2: Add concentrated ammonia solution to step 1 and stir to form a uniform solution;

[0016] Step 3: Inject formaldehyde solution into the uniform solution in step 2 and stir at room temperature under the action of a magnetic stirrer;

[0017] Step 4: After the reaction in step 3, the solution is centrifuged, washed with water, and vacuum dried to obtain a porous carbon material precursor;

[0018] Step 5: Heat the porous carbon material precursor obtained in step 4 in air to an appropriate temperature at a certain heating rate to perform carbonization calcination, and CNS porous carbon material is obtained.

[0019] Step 6: Take an appropriate amount of CNS porous carbon material in step 5 and disperse it in deionized water, and add an appropriate amount of K2PdCl4 aqueous solution, and ultrasonic dispersion to obtain a uniformly dispersed mixed solution A;

[0020] Step 7: Add sodium borohydride as a reducing agent dropwise to the mixed solution A in step 6, and stir at room temperature to obtain a mixed solution B;

[0021] Step 8: Centrifuge and wash the mixed solution B in step 7 to obtain a Pd / NSC nano-catalyst.

[0022] In step 1, the mass ratio of dopamine hydrochloride solid, ethanol and water is 1:40:120; in step 2, the mass fraction of concentrated ammonia solution is 25-28%; in step 3, the mass fraction of formaldehyde solution is 35-37%.

[0023] In step 5, the calcination carbonization temperature is 500-1200℃; the calcination carbonization temperature rising rate is 5℃ / min.

[0024] In step 6, the concentration of the K2PdCl4 aqueous solution is 0.01-0.08mmol / mL.

[0025] In step 7, the reducing agent sodium borohydride and Pd in the K2PdCl4 aqueous solution 2+ The molar ratio of the metal ions is 5-15:1.

[0026] In the method for preparing the Pd / CNS nano-catalyst assisted by transition metal ions to catalyze the hydrogen production from sodium formate, any one of the following steps is adopted: preparing a sodium formate solution with a certain concentration and preparing Fe2(SO4)3, CoSO4, NiSO4, ZnSO4 or CuSO4 solutions with different concentrations.

[0027] The prepared Pd / CNS catalyst is dispersed in deionized water in a 10mL reactor, then the reactor is sealed and placed in a 60-70℃ water bath for magnetic stirring;

[0028] The sodium formate solution is quickly injected into the reactor, and the timing is started at the same time, after 1min of reaction, the prepared metal ion solution is slowly injected into the reactor, and the gas volume at the corresponding time is recorded every 30s.

[0029] The method for preparing the Pd / CNS nano-catalyst assisted by different transition metal ions to catalyze the hydrogen production from sodium formate.

[0030] The equation (Eq.1) for the hydrogen production from the decomposition of sodium formate is:

[0031] HCOONa+H2O→NaOH+CO2↑+H2↑In the application of catalyzing the hydrogen production from the decomposition of sodium formate, the catalyst has high catalytic selectivity, and the initial TOF value of the reaction can be calculated by the following formula:

[0032]

[0033] Wherein t=2min, V(gas) is the gas volume produced in 2min of the sodium formate decomposition reaction. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 (a) is the SEM image of the CNS porous carbon material prepared in Example 1 of the present application.

[0035] Figure 1 (b) is the size distribution graph of the CNS porous carbon material in Example 1 of the present application.

[0036] Figure 2 (a) is a TEM image of Pd / CNS nanocatalyst prepared in Example 1 of the present invention.

[0037] Figure 2 (b) is a histogram of the size of Pd nanoparticles in Pd / CNS catalyst prepared in Example 1 of the present invention. Figure 3 (a) is a TEM image of Pd / CNS nanocatalyst prepared in Example 2 of the present invention. 3+ Figure showing the volume of gas produced over time by the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0038] Figure 3 (b) is a TEM image of Pd / CNS nanocatalyst prepared in Example 3 of the present invention. 3+ Figure showing the volume of gas produced over time by the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0039] Figure 3 (c) is a TEM image of Pd / CNS nanocatalyst prepared in Example 4 of the present invention. 3+ Figure showing the volume of gas produced over time by the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0040] Figure 3 (d) is a TEM image of Pd / CNS nanocatalyst prepared in Example 5 of the present invention. 3+ Figure showing the volume of gas produced over time by the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0041] Figure 4 (a) is a TEM image of Pd / CNS nanocatalyst prepared in Example 2 of the present invention. 3+ Table showing the TOF values and their corresponding yields for the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0042] Figure 4 (b) is a TEM image of Pd / CNS nanocatalyst prepared in Example 3 of the present invention. 3+ Table showing the TOF values and their corresponding yields for the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0043] Figure 4 (c) is a TEM image of Pd / CNS nanocatalyst prepared in Example 4 of the present invention. 3+ Table showing the TOF values and their corresponding yields for the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst.

[0044] Figure 4(d) 1.0 mL of Fe at a concentration of 2.0 mmoL / mL in Example 5 of the present invention 3+ TOF values of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition and their corresponding yields.

[0045] Figure 5 (a) 1.0 mL of Co at a concentration of 1.0 mmoL / mL in Example 6 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition.

[0046] Figure 5 (b) 1.0 mL of Ni at a concentration of 1.0 mmoL / mL in Example 7 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition.

[0047] Figure 5 (c) 1.0 mL of Cu at a concentration of 1.0 mmoL / mL in Example 8 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition.

[0048] Figure 5 (d) 1.0 mL of Zn at a concentration of 1.0 mmoL / mL in Example 9 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition.

[0049] Figure 6 (a) 1.0 mL of Fe at a concentration of 1.0 mmoL / mL in Example 10 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition at different system temperatures.

[0050] Figure 6 (b) Plot of sodium formate decomposition yield and their corresponding TOF values in Example 10 of the present invention.

[0051] Figure 7 (a) 1.0 mL of Fe at a concentration of 1.0 mmoL / mL in Example 11 of the present invention 2+ Plot of gas volume vs. time of ion-assisted Pd / CNS nanocatalyst catalyzing sodium formate decomposition at different catalyst loading.

[0052] Figure 7 (b) Plot of sodium formate decomposition yield and their corresponding TOF values in Example 11 of the present invention. DETAILED DESCRIPTION

[0053] In order to better explain the present application, it is further described in detail below in connection with specific examples and drawings. However, it should not be considered that the above-mentioned content of the present application is limited only to the following examples.

[0054] Example 1

[0055] Method for preparing Pd / CNS nano-catalyst

[0056] Step 1: 0.5 g of dopamine hydrochloride was added to 80 mL of solvent (volume ratio of ethanol: deionized water = 1:3), and stirred thoroughly until dissolved;

[0057] Step 2: 0.7 mL of 28% mass fraction ammonia solution was added to Step 1, and stirred to form a uniform solution;

[0058] Step 3: 0.7 mL of 37% mass fraction formaldehyde solution was injected into the uniform solution in Step 2, and stirred at room temperature under the action of a magnetic stirrer for 40 min;

[0059] Step 4: The solution after reaction in Step 3 was centrifuged at 10000 rpm for 10-20 min, washed with water for 2-3 times, and the solid material obtained by centrifugation was dried under vacuum at 50°C and ground into powder to obtain a porous carbon material precursor;

[0060] Step 5: The porous carbon material precursor obtained in Step 4 was heated to 800°C at a heating rate of 5°C / min in air and calcined for 5 h, i.e. CNS-800 porous carbon material was obtained.

[0061] Step 6: 30 mg of CNS-800 porous carbon material in Step 5 was dispersed in 8 mL of deionized water and 1.0 mL of K2PdCl4 solution with a concentration of 0.02 mmol / mL was added, and ultrasonic dispersion was performed for 10 min to obtain a uniformly dispersed mixed solution A;

[0062] Step 7: 1.0 mL of sodium borohydride with a concentration of 7.57 mg / mL was added dropwise to the mixed solution A described in Step 6 as a reducing agent, and stirred at room temperature for 10 min to obtain a mixed solution B;

[0063] Step 8: The mixed solution B described in Step 7 was centrifuged at 10000 rpm for 1-2 min, and washed with water for 2-3 times to obtain a Pd / CNS catalyst.

[0064] Figure 1 (a) is the SEM image of the CNS porous carbon material prepared in Example 1 of the present application, from which it can be seen that the porous carbon with a spherical structure is prepared. Figure 1(b) is the size distribution chart of the CNS porous carbon material in Example 1 of the present application, it can be seen that the average size of the CNS porous carbon is 1.28 μm.

[0065] Figure 2 (a) is a TEM chart of the Pd / CNS nano-catalyst prepared in Example 1 of the present application, it can be seen from the chart that the Pd 2+ metal ions are uniformly reduced onto the porous carbon spheres. Figure 2 (b) is a particle size size chart of the Pd nanoparticles in the Pd / CNS catalyst prepared in Example 1 of the present application, it can be seen that the Pd / CNS nano-catalyst has a small Pd particle size (6.23 nm), which has a positive effect on the practical application of the Pd / CNS nano-catalyst.

[0066] Example 2

[0067] The Pd / CNS nano-catalyst prepared according to Example 1 is applied to metal Fe 3+ ion-assisted Pd / CNS nano-catalyst catalyzes the decomposition of sodium formate to produce hydrogen.

[0068] Step 1: In a 10 mL reactor, 2% mmol Pd / CNS catalyst prepared in Example 1 is dispersed in 4.0 mL of deionized water, then the reactor is sealed and placed in a 333 K water bath pot for magnetic stirring;

[0069] Step 2: 1.0 mmol of sodium formate solution is quickly injected into the reactor in Step 1, and the timer is started at the same time, after 1 min of reaction, 1.0 mL of Fe 3+ ions with a concentration of 0.5 mmol / mL is slowly injected into the reactor, and the gas volume at the corresponding time is recorded every 30 s.

[0070] Figure 3 (a) is a chart of the relationship between the gas volume and the time of the decomposition of sodium formate catalyzed by the Pd / CNS nano-catalyst assisted by 1.0 mL of Fe 3+ ions with a concentration of 0.5 mmol / mL in Example 2 of the present application.

[0071] Figure 4 (a) is a chart of the relationship between the gas volume and the time of the decomposition of sodium formate catalyzed by the Pd / CNS nano-catalyst assisted by 1.0 mL of Fe 3+ ions with a concentration of 0.5 mmol / mL in Example 2 of the present application. 3+ It can be seen that when the concentration of Fe (H2+CO2) ions is 0.5 M, the TOF is 1473.2 mmol -1 mmol Pd h -1 , and the gas yield is 56.4%.

[0072] Example 3

[0073] Pd / CNS nanocatalyst prepared according to Example 1 was applied to metal Fe 3+ The ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate to produce hydrogen.

[0074] Fe 3+ The ion concentration was changed to 1.0 mmoL / mL, and the other steps were the same as Example 1.

[0075] Figure 3 (b) For 1.0 mL of Fe 3+ The ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate to produce hydrogen.

[0076] Figure 4 (b) For 1.0 mL of Fe 3+ The TOF value of the ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate and its corresponding yield. It can be seen that when the Fe 3+ The TOF was 1757.8 mmol (H2+CO2) mmol -1 Pd h -1 , and the gas yield was 60.8%.

[0077] Example 4

[0078] Pd / CNS nanocatalyst prepared according to Example 1 was applied to metal Fe 3+ The ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate to produce hydrogen.

[0079] Fe 3+ The ion concentration was changed to 1.5 mmoL / mL, and the other steps were the same as Example 1.

[0080] Figure 3 (c) For 1.0 mL of Fe 3+ The ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate to produce hydrogen.

[0081] Figure 4 (c) For 1.0 mL of Fe 3+ The TOF value of the ion-assisted Pd / CNS nanocatalyst catalyzed the decomposition of sodium formate and its corresponding yield. It can be seen that when the Fe 3+The TOF of the Pd / CNS nanocatalyst prepared according to Example 1 is 1657.4 mmol when the concentration of Fe3+ions is 1.0 M (H2+CO2) mmol -1 Pd h -1 The gas yield is 55.8%.

[0082] Example 5

[0083] The Pd / CNS nanocatalyst prepared according to Example 1 is applied to the metal Fe 3+ The Pd / CNS nanocatalyst assisted by Fe3+ions catalyzes the decomposition of sodium formate to produce hydrogen.

[0084] In Example 2, step 2, the Fe3+ions are replaced by Co2+ions with a concentration of 1.0 mmol / mL, and the other steps are the same as in Example 1. 3+ The concentration of Fe3+ions is changed to 2.0 mmol / mL, and the other steps are the same as in Example 1.

[0085] Figure 3 (d) The Pd / CNS nanocatalyst assisted by 1.0 mL of Fe3+ions with a concentration of 2.0 mmol / mL in Example 5 of the present application. 3+ The Pd / CNS nanocatalyst assisted by Fe3+ions catalyzes the decomposition of sodium formate to produce hydrogen.

[0086] Figure 4 (d) The Pd / CNS nanocatalyst assisted by 1.0 mL of Fe3+ions with a concentration of 2.0 mmol / mL in Example 5 of the present application. 3+ The TOF value of the Pd / CNS nanocatalyst assisted by Fe3+ions catalyzing the decomposition of sodium formate and its corresponding yield can be seen. When the concentration of Fe3+ions is 1.0 M, the TOF is 1913.2 mmol 3+ mmol (H2+CO2) -1 Pd h -1 The gas yield is 55.8%.

[0087] Example 6

[0088] The Pd / CNS nanocatalyst prepared according to Example 1 is applied to the metal Co 2+ The Pd / CNS nanocatalyst assisted by Fe3+ions catalyzes the decomposition of sodium formate to produce hydrogen.

[0089] In Example 2, step 2, the Fe3+ions are replaced by Co2+ions with a concentration of 1.0 mmol / mL, and the other steps are the same as in Example 1. 3+ The concentration of Fe3+ions is changed to 2.0 mmol / mL, and the other steps are the same as in Example 1. 2+ The concentration of Fe3+ions is changed to 2.0 mmol / mL, and the other steps are the same as in Example 1.

[0090] Figure 5 (a) The Pd / CNS nanocatalyst assisted by 1.0 mL of Co2+ions with a concentration of 1.0 mmol / mL in Example 6 of the present application. 2+ The Pd / CNS nanocatalyst assisted by Fe3+ions catalyzes the decomposition of sodium formate to produce hydrogen. ​

[0091] Example 7

[0092] Pd / CNS nanocatalyst prepared according to Example 1 was applied to metal Ni 2+ Pd / CNS nanocatalyst assisted by Ni2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0093] Fe3+ion in step 2 in Example 2 was changed to 1.0 mmoL / mL Ni2+ion, and other steps were the same as Example 1. 3+ Pd / CNS nanocatalyst assisted by Ni2+ion catalyzed the decomposition of sodium formate to produce hydrogen. 2+ Pd / CNS nanocatalyst assisted by Ni2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0094] Figure 5 (b) The relationship between gas volume and time of 1.0 mL Pd / CNS nanocatalyst assisted by 1.0 mmoL / mL Ni2+ion catalyzed the decomposition of sodium formate in Example 7 of the present application. 2+ Pd / CNS nanocatalyst assisted by Ni2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0095] Example 8

[0096] Pd / CNS nanocatalyst prepared according to Example 1 was applied to metal Cu 2+ Pd / CNS nanocatalyst assisted by Cu2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0097] Fe3+ion in step 2 in Example 2 was changed to 1.0 mmoL / mL Cu2+ion, and other steps were the same as Example 1. 3+ Pd / CNS nanocatalyst assisted by Cu2+ion catalyzed the decomposition of sodium formate to produce hydrogen. 2+ Pd / CNS nanocatalyst assisted by Cu2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0098] Figure 5 (c) The relationship between gas volume and time of 1.0 mL Pd / CNS nanocatalyst assisted by 1.0 mmoL / mL Cu2+ion catalyzed the decomposition of sodium formate in Example 8 of the present application. 2+ Pd / CNS nanocatalyst assisted by Cu2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0099] Example 9

[0100] Pd / CNS nanocatalyst prepared according to Example 1 was applied to metal Zn 2+ Pd / CNS nanocatalyst assisted by Zn2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0101] Fe3+ion in step 2 in Example 2 was changed to 1.0 mmoL / mL Zn2+ion, and other steps were the same as Example 1. 3+ Pd / CNS nanocatalyst assisted by Zn2+ion catalyzed the decomposition of sodium formate to produce hydrogen. 2+ Pd / CNS nanocatalyst assisted by Zn2+ion catalyzed the decomposition of sodium formate to produce hydrogen.

[0102] Figure 5 (d) The relationship between gas volume and time of 1.0 mL Pd / CNS nanocatalyst assisted by 1.0 mmoL / mL Zn2+ion catalyzed the decomposition of sodium formate in Example 9 of the present application. 2+The relationship between the volume of gas produced by the decomposition of sodium formate catalyzed by ion-assisted Pd / CNS nanocatalyst and time.

[0103] Example 10

[0104] The Pd / CNS nanocatalyst prepared according to Example 1 was applied to the effect of reaction system temperature on the decomposition of sodium formate to produce hydrogen.

[0105] Step 1: Disperse the 2% mmol Pd / CNS catalyst prepared in Example 1 in 4.0 mL of deionized water in a 10 mL reactor, then seal the reactor and place it in a water bath at different temperatures for magnetic stirring;

[0106] Step 2: Rapidly inject 1.0 mmol sodium formate solution into the reactor from Step 1, and start timing simultaneously. After reacting for 1 minute, slowly inject 1.0 mL of 1.0 mmol / mL Fe into the reactor. 3+ Ions, and the gas volume at each 30-second interval.

[0107] Figure 6 (a) is 1.0 mL of Fe with a concentration of 1.0 mmol / mL in Example 10 of the present invention. 2+ The relationship between the volume of gas produced by the decomposition of sodium formate by ion-assisted Pd / CNS nanocatalyst and time at different system temperatures.

[0108] The figure shows the effect of reaction system temperature on Fe 3+ The ion-assisted hydrolysis of sodium formate can be fitted as a linear curve, indicating that the hydrolysis process of sodium formate is related to temperature. Higher temperatures result in a faster reaction rate, higher decomposition yield, and a higher TOF value (e.g., ...). Figure 6 (b) is shown.

[0109] The different temperatures mentioned are 313K, 323K, and 343K.

[0110] Example 11

[0111] The effect of the amount of Pd / CNS nanocatalyst prepared according to Example 1 on the decomposition of sodium formate to produce hydrogen.

[0112] Step 1: Disperse the 2% mmol Pd / CNS catalyst prepared in Example 1 in 4.0 mL of deionized water in a 10 mL reactor, then seal the reactor and place it in a 333 K water bath with magnetic stirring;

[0113] Step 2: Rapidly inject 1.0 mmol sodium formate solution into the reactor from Step 1, and start timing simultaneously. After reacting for 1 minute, slowly inject 1.0 mL of 1.0 mmol / mL Fe into the reactor.3+ The ion, every 30 s, record the corresponding time under the gas volume.

[0114] Figure 7 (a) is the embodiment 11 of the present application 1.0 mL concentration of 1.0 mmoL / mL Fe 2+ The ion assisted Pd / CNS nano-catalyst in different catalyst addition amount catalytic sodium formate decomposition gas volume and time relationship diagram. The amount of catalyst on the Fe 3+ The ion assisted sodium formate hydrolysis process can be fitted as a linear curve, which shows that the hydrolysis process of sodium formate and the amount of catalyst, within a certain range, with the increase of catalyst dosage, the reaction rate is faster, and the decomposition yield is higher (such as Figure 7 (b) shows).

[0115] The amount of catalyst is 1.0 mmol%, 1.5 mmol%, 2.0 mmol%, 2.5 mmol%, respectively.

[0116] The above is the preferred embodiment of the present application, it should be noted that, without departing from the principles of the present application, under the condition of several improvements and modifications, also regarded as the protection scope of the present application.

Claims

1. Use of transition metal ion assisted Pd / CNS nanocatalyst for catalyzing hydrogen production from sodium formate, characterized in that, Pd / C catalyst is obtained by loading metal Pd nanoparticles on a porous carbon material carrier, and then assisted catalysis of sodium formate decomposition to prepare hydrogen gas in the presence of transition metal ions, including any one of Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ , Cu 2+ , the concentration of sodium formate solution is 0.5-2.0mmoL / mL; the ion concentration of any one of Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ , Cu 2+ is 0.1mmoL / mL-3.0mmoL / mL.

2. Use of the transition metal ion-assisted Pd / CNS nanocatalyst to catalyze hydrogen production from sodium formate according to claim 1, characterized in that, The concentration of the sodium formate solution is 1.0 mmol / mL; Fe 3+ , Co 2+ , Ni 2+ , Zn 2+ , Cu 2+ any one of the ions of any one of 0.5 mmoL / mL, 1.0 mmoL / mL, 1.5 mmoL / mL, 2.0 mmoL / mL.

3. Use of the transition metal ion-assisted Pd / CNS nanocatalyst to catalyze hydrogen production from sodium formate according to claim 1, characterized in that, The preparation method of the Pd / CNS nano-catalyst is as follows: Step 1: dissolve a proper amount of dopamine hydrochloride solid in a mixed solution of ethanol and deionized water, and fully stir until completely dissolved; Step 2: add a concentrated ammonia solution to the solution of step 1, and stir to form a uniform solution; Step 3: inject a formaldehyde solution into the uniform solution of step 2, and stir under the action of a magnetic stirrer at room temperature; Step 4: after the reaction of step 3, centrifuge, wash with water, and vacuum dry the solution to obtain a porous carbon material precursor; Step 5: heat the porous carbon material precursor obtained in step 4 in air at a certain heating rate to a proper temperature for calcination and carbonization, and thus obtain a CNS porous carbon material; Step 6: take a proper amount of the CNS porous carbon material of step 5, disperse it in deionized water, and add a proper amount of a K2PdCl4 aqueous solution, and ultrasonically disperse to obtain a uniformly dispersed mixed solution A; Step 7: drop a sodium borohydride as a reducing agent into the mixed solution A of step 6, and stir at room temperature to obtain a mixed solution B; Step 8: centrifuge and wash the mixed solution B of step 7 to obtain a Pd / NSC nano-catalyst.

4. Use of the transition metal ion-assisted Pd / CNS nanocatalyst to catalyze hydrogen production from sodium formate according to claim 3, characterized in that, In step 1, the mass ratio of dopamine hydrochloride solid, ethanol and water is 1:40:120; in step 2, the mass fraction of the concentrated ammonia solution is 25-28%; and in step 3, the mass fraction of the formaldehyde solution is 35-37%.

5. Use of the transition metal ion-assisted Pd / CNS nanocatalyst to catalyze hydrogen production from sodium formate according to claim 3, characterized in that, In step 5, the calcination and carbonization temperature is 500-1200℃, and the temperature rising rate is 5 ℃ / min.

6. Use of the transition metal ion-assisted Pd / CNS nanocatalyst to catalyze hydrogen production from sodium formate according to claim 3, characterized in that, In step 6, the concentration of the K2PdCl4 aqueous solution is 0.01-0.08 mmol / mL.

7. Use of the transition metal ion-assisted Pd / CNS nanocatalyst according to claim 3 for catalyzing hydrogen production from sodium formate, characterized in that, In step 7, the reducing agent sodium borohydride and Pd in the aqueous solution of K2PdCl4 2+ The ratio of the amount of substance of the metal ions is 5-15:1.

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