CN109989084B - Electrocatalyst, preparation method thereof, electrode and water splitting system - Google Patents
Electrocatalyst, preparation method thereof, electrode and water splitting system Download PDFInfo
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- 239000010411 electrocatalyst Substances 0.000 title claims abstract description 110
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- 239000010941 cobalt Substances 0.000 claims description 15
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- 239000001267 polyvinylpyrrolidone Substances 0.000 claims description 7
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- 229910021580 Cobalt(II) chloride Inorganic materials 0.000 claims description 3
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- 229910021586 Nickel(II) chloride Inorganic materials 0.000 claims description 3
- 239000002253 acid Substances 0.000 claims description 3
- 229910000360 iron(III) sulfate Inorganic materials 0.000 claims description 3
- 239000012046 mixed solvent Substances 0.000 claims description 3
- 229910000363 nickel(II) sulfate Inorganic materials 0.000 claims description 3
- 239000005864 Sulphur Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 claims 1
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- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 55
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- 239000001301 oxygen Substances 0.000 abstract description 55
- 230000000694 effects Effects 0.000 abstract description 27
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- 239000002184 metal Substances 0.000 abstract description 27
- 239000002086 nanomaterial Substances 0.000 abstract description 26
- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical compound S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 abstract description 26
- 238000009776 industrial production Methods 0.000 abstract description 8
- 230000003197 catalytic effect Effects 0.000 description 22
- 230000000052 comparative effect Effects 0.000 description 20
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- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 description 14
- 239000000463 material Substances 0.000 description 13
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- 239000000203 mixture Substances 0.000 description 8
- KBJMLQFLOWQJNF-UHFFFAOYSA-N nickel(ii) nitrate Chemical compound [Ni+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O KBJMLQFLOWQJNF-UHFFFAOYSA-N 0.000 description 8
- 238000007254 oxidation reaction Methods 0.000 description 7
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- QPDPTJWTEUDZNA-UHFFFAOYSA-N [Co].S=O Chemical compound [Co].S=O QPDPTJWTEUDZNA-UHFFFAOYSA-N 0.000 description 6
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 6
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
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- MVFCKEFYUDZOCX-UHFFFAOYSA-N iron(2+);dinitrate Chemical compound [Fe+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O MVFCKEFYUDZOCX-UHFFFAOYSA-N 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
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- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/26—Catalysts comprising hydrides, coordination complexes or organic compounds containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24
- B01J31/28—Catalysts comprising hydrides, coordination complexes or organic compounds containing in addition, inorganic metal compounds not provided for in groups B01J31/02 - B01J31/24 of the platinum group metals, iron group metals or copper
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/30—Catalysts, in general, characterised by their form or physical properties characterised by their physical properties
- B01J35/33—Electric or magnetic properties
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/02—Hydrogen or oxygen
- C25B1/04—Hydrogen or oxygen by electrolysis of water
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
- C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
- C25B11/073—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material
- C25B11/091—Electrodes formed of electrocatalysts on a substrate or carrier characterised by the electrocatalyst material consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D5/00—Electroplating characterised by the process; Pretreatment or after-treatment of workpieces
- C25D5/34—Pretreatment of metallic surfaces to be electroplated
- C25D5/38—Pretreatment of metallic surfaces to be electroplated of refractory metals or nickel
- C25D5/40—Nickel; Chromium
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D9/00—Electrolytic coating other than with metals
- C25D9/04—Electrolytic coating other than with metals with inorganic materials
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
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Abstract
The invention provides an electrocatalyst, a preparation method thereof, an electrode and a water splitting system. The electrocatalyst includes: sea urchin-shaped metal oxysulfide nano materials; a complex formed of iron, nickel, and isophthalic acid, the complex attached to an outer surface of the metal oxysulfide nanomaterial. The electrocatalyst has the advantages of high activity of electrocatalytic oxygen evolution reaction, strong stability, simple and controllable preparation process, low cost and easy realization of industrial production.
Description
Technical Field
The invention relates to the technical field of materials, in particular to an electrocatalyst, a preparation method thereof, an electrode and a water splitting system.
Background
With environmental pollution and the energy shortages associated with traditional fossil fuels, sustainable energy harvesting patterns have received much attention. Therefore, the development of clean and sustainable new energy is now on the way. The current energy crisis can be effectively alleviated by electrolyzing water to generate oxygen and hydrogen. However, the rate of the whole water splitting system is hindered by the slow water oxidation reaction in the anode, and the improvement of the water splitting efficiency is seriously hindered. Therefore, it is highly desired to develop an electrocatalyst with high activity and low cost for accelerating the oxidation reaction of water, but the catalytic activity of the current electrocatalyst for electrocatalytic decomposition of water is low.
Thus, the related art of the existing electrocatalysts still needs to be improved.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, one objective of the present invention is to provide an electrocatalyst with high activity, strong stability, simple and controllable preparation process, low cost, or easy realization of industrial production for electrocatalytic oxygen evolution reaction.
In one aspect of the invention, the invention provides an electrocatalyst. According to an embodiment of the invention, the electrocatalyst comprises: sea urchin-shaped metal oxysulfide nano materials; a complex formed of iron, nickel, and isophthalic acid, the complex attached to an outer surface of the metal oxysulfide nanomaterial. The inventor finds that the electrocatalysis oxygen evolution reaction has high activity and strong stability, the preparation process is simple and controllable, the cost is low, and the industrial production is easy to realize.
According to an embodiment of the present invention, the metal oxysulfide nanomaterial comprises nano cobalt oxysulfide.
According to the embodiment of the invention, the nano cobalt oxysulfide is CoS0.28O0.54。
According to the embodiment of the invention, in the electrocatalyst, the mass ratio of the metal oxysulfide nano material to the complex is (1-3): (3-6).
According to an embodiment of the present invention, in the complex, the molar ratio of the iron, the nickel and the isophthalic acid is (0.02 to 0.1): (0.02-0.1): (0.05-0.1).
According to an embodiment of the invention, the complex has the formula [ Fe ]2Ni(H2O)]3O(O2CC6H4CO2)3·9H2O。
According to an embodiment of the invention, the electrocatalyst satisfies at least one of the following conditions: when the current density is 20mA/cm2When the reaction is carried out, the overpotential of the electrocatalytic oxygen evolution reaction is not more than 216 mV; when the potential is 210 mV-260 mV, the catalytic current is kept stable in the electrocatalytic oxygen evolution reaction process of not less than 80000 s.
In another aspect of the invention, the invention provides a method of preparing an electrocatalyst as hereinbefore described. According to an embodiment of the invention, the method comprises: electrodepositing the metal oxysulfide nano material on the surface of the foamed nickel to obtain a prefabricated object; electrodepositing the complex on the surface of the preform to obtain the electrocatalyst. The inventor finds that the method is simple and convenient to operate, easy to implement and easy for industrial production, and the prepared electrocatalyst has high activity and high stability in the electrocatalytic oxygen evolution reaction.
According to an embodiment of the invention, the method comprises: putting foamed nickel into a first electrodeposition solution containing a cobalt source and a sulfur source; electrifying the foamed nickel to enable the first electrodeposition solution to perform a first reaction to obtain a prefabricated object; placing the preform in a second bath comprising an iron source, a nickel source, and isophthalic acid; and electrifying the prefabricated object to enable the second electrodeposition liquid to perform a second reaction so as to obtain the electrocatalyst.
According to an embodiment of the invention, the method satisfies at least one of the following conditions: when the foamed nickel is electrified, the voltage is-1.0V to-0.6V relative to an Ag/AgCl reference electrode filled with saturated KCl solution; electrifying the foamed nickel for 2400-4200 s; when the prefabricated object is electrified, the voltage is-1.5V to-1.0V relative to an Ag/AgCl reference electrode filled with saturated KCl solution; and the time for electrifying the prefabricated object is 3600 s-5400 s.
According to an embodiment of the invention, the method satisfies at least one of the following conditions: the cobalt source comprises Co (NO)3)2、CoCl2And CoSO4At least one of; the sulfur source comprises at least one of peroxythiocarbonic acid, thiopyridine, and thiourea; the iron source comprises Fe (NO)3)3、FeCl3And Fe2(SO4)3At least one of; the nickel source comprises Ni (NO)3)2、NiCl2And NiSO4At least one of; the solvent of the first and/or second bath comprises at least one of N, N-dimethylformamide and deionized water.
According to an embodiment of the invention, the method satisfies at least one of the following conditions: the molar ratio of the iron source to the nickel source to the isophthalic acid is (0.02-0.1): (0.02-0.1): (0.05-0.1), preferably (0.02-0.05): (0.02-0.05): (0.05 to 0.08), more preferably 0.03: 0.03: 0.075; the molar ratio of the cobalt source to the sulfur source is (0.02-0.15): (0.005-0.015), preferably (0.08-0.15): (0.008 to 0.012), more preferably 0.1: 0.01; the solvent of the first electrodeposition solution and/or the second electrodeposition solution is a mixed solvent of the N, N-dimethylformamide and the deionized water, and preferably, the volume ratio of the N, N-dimethylformamide to the deionized water is (1-2): 1.
according to an embodiment of the invention, the second bath is obtained by: dissolving the isophthalic acid in the N, N-dimethylformamide to obtain a first prefabricated liquid; dissolving the iron source in the deionized water to obtain a second prefabricated liquid; adding the second prefabricated liquid into the first prefabricated liquid, and stirring the obtained third prefabricated liquid; adding the N, N-dimethylformamide into the third prefabricated liquid to obtain a fourth prefabricated liquid; adding the nickel source to the fourth preformation liquor to obtain the second electrodeposition liquor.
According to an embodiment of the present invention, before the step of placing the foamed nickel into the first electrodeposition bath, the method further comprises: and carrying out acidification treatment on the foamed nickel.
According to an embodiment of the present invention, the acidification treatment of the nickel foam is performed by soaking the nickel foam in an acidic solution.
According to an embodiment of the invention, the acidic solution comprises hydrochloric acid.
According to the embodiment of the invention, the concentration of the hydrochloric acid is 2-4 mol/L.
According to the embodiment of the invention, the time of the acidification treatment is 20-40 min.
According to an embodiment of the present invention, the acidification treatment is performed under ultrasonic agitation.
According to an embodiment of the invention, before placing the preparation in the second bath, the method further comprises: and putting the prefabricated object into a solution containing a surfactant for surface modification treatment.
According to an embodiment of the invention, the surfactant comprises polyvinylpyrrolidone.
According to the embodiment of the invention, in the solution containing the surfactant, the concentration of the surfactant is 0.015 g/mL-0.04 g/mL.
According to the embodiment of the invention, the time of the surface modification treatment is 6-10 h.
In yet another aspect of the invention, an electrode is provided. According to an embodiment of the invention, at least a part of the electrode is formed by an electrocatalyst as described above. The inventors have found that the electrode allows the efficiency of the oxygen evolution reaction to be significantly improved.
In yet another aspect of the invention, a water splitting system is provided. According to an embodiment of the invention, the water splitting system comprises: a power source; a cathode electrically connected to a positive electrode of the power supply; and an anode electrically connected to the negative electrode of the power supply, at least a portion of the anode being formed by the electrode. The inventor finds that the water splitting system has high water splitting efficiency and good commercial prospect.
Drawings
Fig. 1 shows a schematic structural view of an electrocatalyst according to an embodiment of the invention.
Figure 2 shows a schematic flow diagram of a method of preparing an electrocatalyst according to one embodiment of the invention.
Figure 3 shows a schematic flow diagram of a method of preparing an electrocatalyst according to another embodiment of the invention.
FIG. 4 shows a schematic flow chart of the steps for preparing a second bath according to one embodiment of the present invention.
Figure 5 shows a schematic flow diagram of a method of preparing an electrocatalyst according to yet another embodiment of the invention.
Fig. 6 shows a schematic flow diagram of a method of preparing an electrocatalyst according to yet another embodiment of the invention.
FIG. 7 shows a schematic diagram of a water splitting system in accordance with an embodiment of the present invention.
FIG. 8 shows a scanning electron micrograph of the preform (a) and the electrocatalyst (b and c) according to example 1 of the present invention, wherein the scale bar in panel b is 5 microns and the scale bar in panel c is 1 micron.
FIG. 9 shows polarization curves of electrocatalysts of example 1, comparative example 1 and comparative example 2 of the present invention at the time of catalytic oxygen evolution reaction (wherein a is the polarization curve of the electrocatalysts of example 1 at the time of catalytic oxygen evolution reaction; b is the polarization curve of the electrocatalysts of comparative example 1 at the time of catalytic oxygen evolution reaction; and c is the polarization curve of the electrocatalysts of comparative example 2 at the time of catalytic oxygen evolution reaction).
FIG. 10 shows the polarization curves of the electrocatalysts of examples 2, 3 and 4 of the present invention at the time of catalytic oxygen evolution reaction (where d is the polarization curve of the electrocatalysts of example 2 at the time of catalytic oxygen evolution reaction; e is the polarization curve of the electrocatalysts of example 3 at the time of catalytic oxygen evolution reaction; and f is the polarization curve of the electrocatalysts of example 4 at the time of catalytic oxygen evolution reaction).
FIG. 11 shows the polarization curves of the electrocatalysts of examples 5 and 6 of the invention during the catalytic oxygen evolution reaction (where g is the polarization curve of the electrocatalysts of example 5 during the catalytic oxygen evolution reaction and h is the polarization curve of the electrocatalysts of example 6 during the catalytic oxygen evolution reaction).
Figure 12 shows the chronopotentiometric curve of the electrocatalyst of example 1 of the invention.
Reference numerals:
1: the electrocatalyst 2: metal oxysulfide nanomaterial 3: the complex 10: water splitting system 100: power supply 200: cathode 300: anode
Detailed Description
The following describes embodiments of the present invention in detail. The following examples are illustrative only and are not to be construed as limiting the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.
In one aspect of the invention, the invention provides an electrocatalyst. According to an embodiment of the present invention, referring to fig. 1, the electrocatalyst 1 comprises: sea urchin-shaped metal oxysulfide nano-materials 2; a complex 3 formed of iron, nickel and isophthalic acid, the complex 3 being attached on an outer surface of the metal oxysulfide nanomaterial 2. The inventor finds that the electrocatalyst 1 has high activity of electrocatalytic oxygen evolution reaction, strong stability, simple and controllable preparation process, low cost and easy realization of industrial production.
According to the embodiment of the invention, as can be understood by those skilled in the art, the sea urchin shape is similar to the shape of sea urchin, and the electrocatalyst 1 of the invention adopts the sea urchin-shaped metal sulfur oxide nano material 2, so that the electrocatalyst oxygen evolution reaction has high activity and strong stability.
According to an embodiment of the present invention, the metal oxysulfide nanomaterial may include nano cobalt oxysulfide. The inventor finds that when the metal oxysulfide nano material is nano cobalt oxysulfide, the activity of the electrocatalytic oxygen evolution reaction is higher, and the stability is stronger.
According to an embodiment of the present invention, further, the nano cobalt oxysulfide is CoS0.28O0.54. Thus, CoS0.28O0.54The metal oxysulfide nano material and the complex formed by the iron, the nickel and the isophthalic acid can better generate a synergistic effect, and the catalytic activities of the metal oxysulfide nano material and the complex formed by the iron, the nickel and the isophthalic acid are exerted more fully, so that the activity of the electrocatalytic oxygen evolution reaction of the electrocatalyst is further improved, and the stability is further enhanced.
According to the embodiments of the present invention, after further research on the mixture ratio between the metal oxysulfide nano material and the complex in the electrocatalyst, the inventors surprisingly found that, in the electrocatalyst with the structure of the present application, the mass ratio between the metal oxysulfide nano material and the complex is (1-3): (3-6), the electrocatalyst can achieve a good catalytic effect, and specifically, in the electrocatalyst, the mass ratio of the metal oxysulfide nanomaterial to the complex is 1: 2, etc. Therefore, in the electrocatalyst, only a small amount of the complex is used, the activity of electrocatalytic oxygen evolution reaction is high, and the stability is strong.
According to the embodiments of the present invention, after a great deal of research, the inventors have found that the molar ratio of the iron, the nickel and the isophthalic acid in the complex may be (0.02 to 0.1): (0.02-0.1): (0.05-0.1). Specifically, in some embodiments of the present invention, the molar ratio of the iron, the nickel, and the isophthalic acid in the complex may be specifically 0.03: 0.03: 0.075, and the like. Therefore, when the iron, the nickel and the isophthalic acid in the complex have the molar ratio as described above, the complex has better electrocatalytic water decomposition activity and stronger stability.
According to the embodiments of the present invention, the inventors have conducted extensive and intensive studies and experimental verification on the molar ratios of the iron, the nickel and the isophthalic acid in the above-mentioned complex, and then found that when the complex is [ Fe ]2Ni(H2O)]3O(O2CC6H4CO2)3·9H2O, which is capable of reacting with metal oxysulfide nanomaterials, especially CoS0.28O0.54The mutual cooperation plays a sufficient synergistic effect, so that the activity of the electrocatalysis oxygen evolution reaction of the electrocatalyst is further improved, and the stability is further enhanced.
According to an embodiment of the invention, the electrocatalyst satisfies at least one of the following conditions: when the current density is 20mA/cm2When the overpotential for the electrocatalytic oxygen evolution reaction is not more than 216mV, specifically, in some embodiments of the present invention, the overpotential for the electrocatalytic oxygen evolution reaction can be 210mV, 211mV, 212mV, 213mV, 214mV, 215mV, or 216mV, and the like; the catalytic current remains stable during the electrocatalytic oxygen evolution reaction at a potential of 210mV to 260mV, and in particular may be 216mV, and in some embodiments of the invention, during the electrocatalytic oxygen evolution reaction at a potential of not less than 80000s, and in particular, not less than 800000 s, 81000s, 82000s, 83000s, 84000s, and 85000s (it is to be noted that the "oxygen evolution reaction" or the "water oxidation reaction" described herein is a half reaction of the water decomposition reaction). Whereby the electrocatalyst is electrically chargedThe catalytic oxygen evolution reaction has high activity and excellent stability, is particularly suitable for serving as a catalyst of a water decomposition system, and has good commercial prospect.
In another aspect of the invention, the invention provides a method of preparing an electrocatalyst as hereinbefore described. According to an embodiment of the invention, referring to fig. 2, the method comprises the steps of:
s100: and electrodepositing the metal oxysulfide nano material on the surface of the foamed nickel to obtain a prefabricated object.
S200: electrodepositing the complex on the surface of the preform to obtain the electrocatalyst.
According to the embodiment of the invention, the foam nickel can be in the form of a conductive strip, a cube, a sphere and the like. In some embodiments of the invention, the nickel foam is in the form of an electrically conductive strip, which may have a gauge of 3cm (0.8 cm-2 cm) x (0.6 cm-1.8 cm). Specifically, it may be 3cm × 1cm × 0.6 cm. Therefore, the operation is simple and convenient, the realization is easy, and the size is better.
According to the embodiment of the present invention, the preparation of the sea urchin-shaped metal oxysulfide nano material on the surface is obtained by the electrodeposition method according to the above S100 and S200, and then the electrocatalyst is obtained by the electrodeposition method, wherein the open porous structure of the sea urchin-shaped metal oxysulfide nano material is favorable for the exposure of active sites, the transmission of substances and electrons, the growth of the complex and the desorption of oxygen. Therefore, the obtained electrocatalyst has the advantages of controllable components, high specific surface area, high activity of electrocatalytic oxygen evolution reaction, strong stability, simple and controllable preparation process, low cost and easy realization of industrial production.
In further embodiments of the present invention, specifically referring to fig. 3, the method may comprise the steps of:
s110: the nickel foam is placed in a first bath containing a cobalt source and a sulfur source.
According to an embodiment of the invention, said cobalt source comprises Co (NO)3)2、CoCl2And CoSO4At least one of (1). Therefore, the material source is wide, the material source is easy to obtain, the cost is low, and the electrocatalyst can be effectively prepared and obtained.
According to an embodiment of the present invention, the sulfur source comprises at least one of peroxythiocarbonic acid, thiopyridine, and thiourea. Therefore, the material source is wide, the material source is easy to obtain, the cost is low, and the electrocatalyst can be effectively prepared and obtained.
According to an embodiment of the invention, the molar ratio of the cobalt source to the sulfur source is (0.02-0.15): (0.005-0.015), and in some embodiments of the invention, further, the molar ratio of the cobalt source and the sulfur source may be (0.08-0.15): (0.008 to 0.012), and further, the molar ratio of the cobalt source to the sulfur source may be 0.1: 0.01. therefore, the electrocatalyst can be effectively prepared, and the prepared electrocatalyst has high activity and high stability in the electrocatalytic oxygen evolution reaction.
S120: and electrifying the foamed nickel to enable the first electrodeposition solution to perform a first reaction to obtain a prefabricated object.
According to an embodiment of the invention, the voltage is between-1.0V and-0.6V relative to an Ag/AgCl reference electrode filled with a saturated KCl solution when the nickel foam is energized. Specifically, the voltage may be-1.0V, -0.9V, -0.8V, -0.7V, or-0.6V, etc. Therefore, the voltage for electrifying the foamed nickel is proper, the stable electrocatalyst can be obtained, and the prepared electrocatalyst has high activity and strong stability in the electrocatalytic oxygen evolution reaction.
According to the embodiment of the invention, the time for electrifying the foamed nickel is 2400 s-4200 s. In some specific embodiments of the present invention, the time for electrifying the nickel foam may be 2400s, 2600s, 2800s, 3000s, 3200s, 3400s, 3600s, 3800s, 4000s, 4200s, or the like. Therefore, the time for electrifying the foamed nickel is proper, the stable electrocatalyst can be obtained, and the prepared electrocatalyst has high activity and strong stability in the electrocatalytic oxygen evolution reaction.
According to an embodiment of the present invention, it can be understood by those skilled in the art that the first reaction may include an electrodeposition reaction of a cobalt source and a sulfur source in the first electrodeposition solution, and further include a chemical reaction in which the cobalt source and the sulfur source are combined to form the metal nano cobalt oxysulfide, which is not described in detail herein.
According to embodiments of the present invention, the solvent of the first bath may include N, N-dimethylformamide, deionized water, and the like. In some specific embodiments of the present invention, the solvent of the first electrodeposition solution is a mixed solvent of the N, N-dimethylformamide and the deionized water, and further, the volume ratio of the N, N-dimethylformamide to the deionized water is (1-2): 1. thus, the first electrodeposition liquid can be preferably subjected to the first reaction to obtain a preform.
S210: the preform is placed in a second bath comprising an iron source, a nickel source, and isophthalic acid.
According to an embodiment of the invention, the iron source comprises Fe (NO)3)3、FeCl3And Fe2(SO4)3At least one of (1). Therefore, the material source is wide, the material source is easy to obtain, the cost is low, and the electrocatalyst can be effectively prepared and obtained.
According to an embodiment of the invention, the nickel source comprises Ni (NO)3)2、NiCl2And NiSO4At least one of (1). Therefore, the material source is wide, the material source is easy to obtain, the cost is low, and the electrocatalyst can be effectively prepared and obtained.
According to an embodiment of the present invention, the molar ratio of the iron source, the nickel source and the isophthalic acid is (0.02 to 0.1): (0.02-0.1): (0.05-0.1), further, in some embodiments of the invention, the molar ratio of the iron source, the nickel source, and the isophthalic acid may be (0.02-0.05): (0.02-0.05): (0.05 to 0.08), and further, the molar ratio of the iron source, the nickel source and the isophthalic acid may be 0.03: 0.03: 0.075. therefore, the electrocatalyst can be effectively prepared, and the prepared electrocatalyst has high activity and high stability in the electrocatalytic oxygen evolution reaction.
S220: and electrifying the prefabricated object to enable the second electrodeposition liquid to perform a second reaction so as to obtain the electrocatalyst.
According to an embodiment of the invention, the voltage is-1.5V to-1.0V relative to an Ag/AgCl reference electrode filled with a saturated KCl solution when the preform is energized. Specifically, the voltage may be-1.5V, -1.4V, -1.3V, -1.2V, -1.1V, or-1.0V, etc. Therefore, the voltage for electrifying the prefabricated part is proper, the stable electrocatalyst can be obtained, and the prepared electrocatalyst has high activity and strong stability in the electrocatalytic oxygen evolution reaction.
According to the embodiment of the invention, the time for electrifying the foam nickel is 3600s to 5400 s. In some specific embodiments of the present invention, the time for energizing the nickel foam may be 3600s, 4000s, 4200s, 4400s, 4600s, 4800s, 5000s, 5200s, 5300s, 5400s, and the like. Therefore, the time for electrifying the prefabricated part is proper, the stable electrocatalyst can be obtained, and the prepared electrocatalyst has high activity and strong stability in the electrocatalytic oxygen evolution reaction.
According to an embodiment of the present invention, it can be understood by those skilled in the art that the second reaction may include an electrodeposition reaction of an iron source and a nickel source in the second electrodeposition solution, and further include a coordination reaction in which the iron source, the nickel source and isophthalic acid combine to form the aforementioned complex, which will not be described in detail herein.
According to an embodiment of the present invention, the solvent of the second bath is the same as the solvent of the first bath, and therefore, redundant description thereof is omitted.
According to an embodiment of the invention, and in particular with reference to fig. 4, the second bath described above may be obtained by:
s10: and dissolving the isophthalic acid in the N, N-dimethylformamide to obtain a first prefabricated liquid.
S20: and dissolving the iron source in the deionized water to obtain a second prefabricated liquid.
S30: and adding the second prefabricated liquid into the first prefabricated liquid, and stirring the obtained third prefabricated liquid.
S40: and adding the N, N-dimethylformamide into the third prefabricated liquid to obtain a fourth prefabricated liquid.
S50: adding the nickel source to the fourth preformation liquor to obtain the second electrodeposition liquor.
According to the embodiment of the invention, the second electrodeposition solution prepared according to the steps and the sequence has better effect when being used for forming the complex.
According to embodiments of the present invention, it will be understood by those skilled in the art that the first and second electrodeposition solutions further comprise a supporting electrolyte, wherein the supporting electrolyte may be potassium chloride or ammonium chloride, and the amount of the supporting electrolyte added is conventional and will not be described in detail herein.
In still other embodiments of the present invention, referring to fig. 5, prior to placing the nickel foam in the first bath, the method further comprises:
s300: and carrying out acidification treatment on the foamed nickel.
According to an embodiment of the present invention, the nickel foam is acidified by soaking the nickel foam in an acidic solution. In some embodiments of the invention, the acidic solution may comprise a hydrochloric acid solution. The concentration of the hydrochloric acid solution may be 2mol/L to 4mol/L, specifically, 2mol/L, 3mol/L, 4mol/L, or the like. The soaking time is 20min to 40min, specifically, 20min, 30min, 40min and the like. Therefore, the method is simple and convenient to operate, easy to realize, easy for industrial production and good in acidification treatment effect.
According to an embodiment of the invention, the acidification treatment is performed under ultrasonic agitation. Therefore, the foamed nickel can be more fully acidified, the effect is better, the subsequent reaction is facilitated, and the stability of the prepared complex is better; meanwhile, the method is simple to operate, convenient and controllable, easy to realize and easy for industrial production.
According to the embodiment of the invention, after the nickel foam is subjected to the acidification treatment, the nickel foam after the acidification treatment can be cleaned. The cleaning can be carried out by adopting deionized water, and can also be carried out by adopting a method that the volume ratio is 1: (1-2) in a mixed solution of acetone and ethanol. Therefore, the cleaning effect is better.
In still other embodiments of the present invention, referring to fig. 6, prior to placing the preform in the second bath, the method further comprises:
s400: and putting the prefabricated object into a solution containing a surfactant for surface modification treatment.
According to an embodiment of the invention, the surfactant comprises polyvinylpyrrolidone (PVP). Therefore, the material source is wide and easy to obtain, the cost is low, and the surface of the prefabricated object subjected to surface modification treatment by the surfactant is easier to form the complex, so that the electrocatalysis oxygen evolution reaction of the electrocatalyst has higher activity and higher stability.
According to the embodiment of the invention, in the solution containing the surfactant, the concentration of the surfactant is 0.015 g/mL-0.04 g/mL. In some embodiments of the invention, the concentration of the surfactant may specifically be 0.015g/mL, 0.02g/mL, 0.03g/mL, or 0.04g/mL, and the like. Therefore, the complex is more easily formed on the surface of the prefabricated object, so that the activity of the electrocatalytic oxygen evolution reaction of the electrocatalyst is higher, and the stability is stronger.
According to the embodiment of the invention, the time of the surface modification treatment is 6-10 h. In some embodiments of the present invention, the time of the surface modification treatment may be 6h, 7h, 8h, 9h, 10h, or the like. Therefore, the time of the surface modification treatment is proper, and the complex is further formed on the surface of the prefabricated object more easily, so that the activity of the electrocatalytic oxygen evolution reaction of the electrocatalyst is higher, and the stability is higher.
In yet another aspect of the invention, an electrode is provided. According to an embodiment of the invention, at least a part of the electrode is formed by an electrocatalyst as described above. The inventors have found that the electrode allows the efficiency of the oxygen evolution reaction to be significantly improved.
In yet another aspect of the invention, a water splitting system is provided. Referring to fig. 7, the water splitting system 10 includes, in accordance with an embodiment of the present invention: a power supply 100; a cathode 200, the cathode 200 being electrically connected to the positive electrode of the power supply 100; and an anode 300, wherein the anode 300 is electrically connected to the negative electrode of the power supply 100, and at least a portion of the anode 300 is formed by the catalyst (note that, the electrical connection method described herein may be any type of electrical connection method, such as electrical connection through a wire). The inventors have found that the water splitting system 10 has high water splitting efficiency and good commercial prospects.
According to an embodiment of the present invention, the cathode 200 and the anode 300 may include conventional electrode materials, such as a glassy carbon electrode, a noble metal electrode, and the like, and the foregoing catalyst and conventional electrode materials together form the anode 300. Therefore, the material source is wide and easy to obtain.
According to the embodiment of the present invention, since the electrocatalyst is prepared by using the nickel foam as the substrate, the nickel foam has a certain space structure and excellent electrical conductivity, the prepared catalyst can be directly connected to a power supply to be used as the anode 300 of the water splitting system 10, and further, the operation is simple, convenient, easy to implement, easy to industrialize and low in cost.
Those skilled in the art will appreciate that the power supply 100 may comprise a power supply used in a conventional water splitting system, according to embodiments of the present invention, and will not be described in detail herein.
In accordance with embodiments of the present invention, it will be understood by those skilled in the art that the water splitting system 10 includes the structure, components, etc. of a conventional water splitting system in addition to the structure described above, and will not be described in detail herein.
The following examples are described in detail with respect to the nickel foam of 1 × 3cm size from the commercial division of the source battery of Yingze, Taiyuan2。
Example 1
This example provides a method for preparing an electrocatalyst, including the steps of:
1) putting the foamed nickel into a hydrochloric acid solution with the concentration of 3mol/L, performing ultrasonic treatment for 30min, washing with water, and putting the foamed nickel into a container with the volume ratio of 1: 1, performing ultrasonic treatment for 30min again in the mixed solution of ethanol and acetone; taking out, washing with water, and oven drying.
2) Cobalt chloride and thiourea are added according to the proportion of 0.1 mol/L: adding cobalt chloride and thiourea into 20mL of deionized water by 0.01mol/L meter, stirring until the cobalt chloride and the thiourea are completely dissolved, taking the processed clean foamed nickel as a working electrode, building a three-electrode system, connecting a CHI-600E electrochemical workstation system controlled by a computer, applying a voltage of-0.8V relative to the Ag/AgCl reference electrode, and reacting for 3600 seconds to obtain the sea urchin-shaped metal oxysulfide nano material in situ grown on the foamed nickel to obtain the prefabricated object.
3) And (3) placing the prefabricated object obtained in the step 2) into 10mL of solution dissolved with 0.2g of PVP, stirring for 8h, taking out the PVP modified nickel foam, washing with deionized water for several times, placing in a 60 ℃ oven for drying, and reserving for the next step of synthesis.
4) Taking isophthalic acid as 0.075mol/L, stirring and dissolving a proper amount of isophthalic acid in 5mL of N, N-dimethylformamide, and marking as a first prefabricated liquid; stirring and dissolving ferric nitrate into 10mL of deionized water by 0.03mol/L of ferric nitrate, and marking as a second solution prefabricated liquid; after the second preformulation was slowly added to the first preformulation while stirring, 5mL of N, N-dimethylformamide was added to the third preformulation of the mixture until a clear solution was obtained, which was designated as the fourth preformulation. Then, nickel nitrate and 0.12g of ammonium chloride are added into the fourth pre-prepared solution respectively according to the proportion of 0.03mol/L of nickel nitrate, and the second electrodeposition solution is obtained after full stirring.
5) And (3) placing the preformed object modified by PVP in the step 3) as a working electrode in the second electrodeposition solution prepared in the step 4), building a three-electrode system, connecting a computer-controlled CHI-600E electrochemical workstation system, applying a voltage of-1.5V relative to an Ag/AgCl reference electrode, and carrying out electrodeposition reaction for 5400 seconds, namely, growing a complex formed by iron, nickel and isophthalic acid on the outer surface of the metal oxysulfide nano material in the preformed object in situ, namely obtaining the electrocatalyst.
Examples 2 to 4
This example provides a method for preparing an electrocatalyst, which is different from example 1 only in that the electrodeposition reaction time in step 5) of example 1 is adjusted to 3600s, 6000s, and 7200s, respectively.
Examples 5 and 6
This example provides a method for preparing an electrocatalyst, which differs from example 1 only in that the concentrations of iron nitrate and nickel nitrate in step 4) were set to 0.05mol/L and 0.03mol/L, respectively, in example 5; example 6 was 0.03mol/L and 0.05 mol/L.
Comparative example 1
This comparative example provides a method for preparing an electrocatalyst, which differs from example 1 only in that no ferric nitrate is added in step 4), and step 4) in this comparative example is specifically as follows:
4) taking isophthalic acid as 0.075mol/L, stirring and dissolving a proper amount of isophthalic acid in 5mL of N, N-dimethylformamide, and marking as a first prefabricated liquid; stirring and dissolving nickel nitrate into 10mL of deionized water by 0.03mol/L of nickel nitrate, and marking as a second solution prefabricated liquid; after the second preformulation was slowly added to the first preformulation while stirring, 5mL of N, N-dimethylformamide was added to the third preformulation of the mixture until a clear solution was obtained, which was designated as the fourth preformulation. Next, 0.12g of ammonium chloride was added to the fourth preliminary solution, and the mixture was sufficiently stirred to obtain a second electrodeposition solution.
Comparative example 2
This comparative example provides a method for preparing an electrocatalyst, which differs from example 1 only in that no nickel nitrate is added in step 4), and step 4) in this comparative example is specifically as follows:
4) taking isophthalic acid as 0.075mol/L, stirring and dissolving a proper amount of isophthalic acid in 5mL of N, N-dimethylformamide, and marking as a first prefabricated liquid; stirring and dissolving ferric nitrate into 10mL of deionized water by 0.03mol/L of ferric nitrate, and marking as a second solution prefabricated liquid; after the second preformulation was slowly added to the first preformulation while stirring, 5mL of N, N-dimethylformamide was added to the third preformulation of the mixture until a clear solution was obtained, which was designated as the fourth preformulation. Next, 0.12g of ammonium chloride was added to the fourth preliminary solution, and the mixture was sufficiently stirred to obtain a second electrodeposition solution.
Comparative example 3
The present comparative example provides a method of preparing an electrocatalyst, comprising the steps of:
1) putting the foamed nickel into a hydrochloric acid solution with the concentration of 3mol/L, performing ultrasonic treatment for 30min, washing with water, and putting the foamed nickel into a container with the volume ratio of 1: 1, performing ultrasonic treatment for 30min again in the mixed solution of ethanol and acetone; taking out, washing with water, and oven drying.
2) Taking isophthalic acid as 0.075mol/L, stirring and dissolving a proper amount of isophthalic acid in 5mL of N, N-dimethylformamide, and marking as a first prefabricated liquid; stirring and dissolving ferric nitrate into 10mL of deionized water by 0.03mol/L of ferric nitrate, and marking as a second solution prefabricated liquid; after the second preformulation was slowly added to the first preformulation while stirring, 5mL of N, N-dimethylformamide was added to the third preformulation of the mixture until a clear solution was obtained, which was designated as the fourth preformulation. Then, nickel nitrate and 0.12g of ammonium chloride are added into the fourth pre-prepared solution respectively according to the proportion of 0.03mol/L of nickel nitrate, and the mixture is fully stirred to obtain the first electrodeposition solution.
3) Placing the foamed nickel treated in the step 1) as a working electrode in the first electrodeposition solution prepared in the step 2), building a three-electrode system, connecting a computer-controlled CHI-600E electrochemical workstation system, applying a voltage of-1.5V relative to an Ag/AgCl reference electrode, and performing electrodeposition reaction for 5400 seconds, namely in-situ growing a complex formed by iron, nickel and isophthalic acid on the outer surface of the foamed nickel, namely obtaining the electrocatalyst.
In a KOH solution with the concentration of 1mol/L, the catalytic performance of the prepared electrocatalyst on oxygen evolution reaction is researched, and the electrochemical performance test result shows that the electrocatalyst has the current density of 20mA/cm2The desired overpotential is 233 mV.
Comparative example 4
The present comparative example provides a method of preparing an electrocatalyst, comprising the steps of:
1) putting the foamed nickel into a hydrochloric acid solution with the concentration of 3mol/L, performing ultrasonic treatment for 30min, washing with water, and putting the foamed nickel into a container with the volume ratio of 1: 1, performing ultrasonic treatment for 30min again in the mixed solution of ethanol and acetone; taking out, washing with water, and oven drying.
2) Cobalt chloride and thiourea are added according to the proportion of 0.1 mol/L: adding cobalt chloride and thiourea into 20mL of deionized water by 0.01mol/L meter, stirring until the cobalt chloride and the thiourea are completely dissolved, taking the processed clean foamed nickel as a working electrode, building a three-electrode system, connecting a CHI-600E electrochemical workstation system controlled by a computer, applying a voltage of-0.8V relative to the Ag/AgCl reference electrode, reacting for 3600 seconds, and growing the echinoid metal oxysulfide nano material on the foamed nickel in situ,
in a KOH solution with the concentration of 1mol/L, the catalytic performance of the prepared electrocatalyst on oxygen evolution reaction is researched, and the electrochemical performance test result shows that the electrocatalyst has the current density of 20mA/cm2When the voltage is higher than 289mV, the required overpotential is 289 mV.
Experimental methods and experimental results:
the electrocatalysts prepared in examples 1 to 6 were tested for their electrocatalytic water oxidation performance in KOH solution (pH 14) at a concentration of 1 mol/L. The specific operation is as follows:
a standard three-electrode system is adopted, the electrocatalyst described above is used as a working electrode, an Ag/AgCl electrode is used as a reference electrode, a carbon rod is used as a counter electrode, linear scanning cyclic voltammetry tests are respectively carried out on the electrocatalysts prepared in the examples 1-6 and the comparative examples 1 and 2, wherein the electrolyte is a KOH solution with the concentration of 1mol/L, water oxidation catalytic performance measurement is carried out at the sweep rate of 2mV/s within the range of an applied potential window of 0V-1.0V, and the change of electrode current along with the scanning potential is recorded.
1. Fig. 8 shows scanning electron micrographs of the preformed object (a) and the electrocatalyst (b and c) prepared in example 1, which indicate that the prepared electrocatalyst has a multi-stage structure morphology, and the complex 3 is attached to the surface of the sea urchin-shaped metal oxysulfide nanomaterial 2, thereby facilitating contact between the electrocatalyst and hydroxyl, desorption of oxygen and exposure of active sites.
2. Fig. 9 shows polarization curves of the electrocatalysts of example 1 and comparative examples 1, 2 in the catalytic oxygen evolution reaction. It is clear from the figure that the electrocatalyst prepared in example 1 was at 20mA cm-2Now, the overpotential for catalyzing the oxygen evolution reaction is 216mV (as shown in a of fig. 9), and the overpotential value required is lower for comparative example 1(259mV as shown in b of fig. 9), comparative example 2(257mV as shown in c of fig. 9), comparative example 3(255mV), and comparative example 4(289mV), indicating that the electrocatalyst obtained in example 1 has better water oxidation catalytic performance. It should be noted that the overpotential data in this experiment are all converted into values relative to the potential of the reversible hydrogen standard electrode, and the calculation process is as follows: reversible hydrogen standard electrode potential of ERHEThe overpotential is η, and η ═ E is determined according to the relation between the potential of the reversible hydrogen standard electrode and the overpotentialRHE1.229V. In the present invention, E is read from the polarization curve of water oxidation reactionRHEThereby obtaining an overpotential η.
3. FIG. 10 is a polarization curve of the electrocatalysts prepared in examples 2 to 4 when catalyzing an oxygen evolution reaction. As can be clearly seen from the figure:
electrocatalyst prepared in example 2 at 20mA cm-2The overpotential for catalyzing the oxygen evolution reaction was 238mV (see d in FIG. 10).
Electrocatalyst prepared in example 3 at 20mA cm-2The overpotential for catalyzing the oxygen evolution reaction was 229mV (e in fig. 10).
Electrocatalyst prepared in example 4 at 20mA cm-2The overpotential for catalyzing the oxygen evolution reaction was 254mV (f in FIG. 10).
4. FIG. 11 is a polarization curve of the electrocatalysts prepared in examples 5 and 6 when catalyzing an oxygen evolution reaction. As can be clearly seen from the figure:
electrocatalyst prepared in example 5 at 20mA cm-2Next, the overpotential for catalyzing the oxygen evolution reaction was 253mV (g in FIG. 11).
Electrocatalyst prepared in example 6 at 20mA cm-2The overpotential for catalyzing the oxygen evolution reaction was 237mV (see h in FIG. 11).
5. FIG. 12 shows the stability test of the electrocatalyst in example 1, set to a current density of 20mA cm using chronopotentiometry-2，50mA cm-2，90mA cm-2，170mA cm-2The change of the current density with time in 80000s is recorded. The chronopotentiometric curve shows that the product has strong structural stability.
In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (17)
1. A method of making an electrocatalyst, comprising:
putting foamed nickel into a first electrodeposition solution containing a cobalt source and a sulfur source;
electrifying the foamed nickel to enable the first electrodeposition solution to perform a first reaction to obtain a prefabricated object;
placing the preform in a second bath comprising an iron source, a nickel source, and isophthalic acid;
energizing the preform to cause a second reaction of the second bath to produce the electrocatalyst,
when the foamed nickel is electrified, the voltage is-1.0V to-0.6V relative to an Ag/AgCl reference electrode filled with saturated KCl solution;
electrifying the foamed nickel for 2400-4200 s;
when the prefabricated object is electrified, the voltage is-1.5V to-1.0V relative to an Ag/AgCl reference electrode filled with saturated KCl solution;
the time for electrifying the prefabricated object is 3600 s-5400 s,
the cobalt source comprises Co (NO)3)2、CoCl2And CoSO4At least one of;
the sulfur source comprises at least one of peroxythiocarbonic acid, thiopyridine, and thiourea;
the iron source comprises Fe (NO)3)3、FeCl3And Fe2(SO4)3At least one of;
the nickel source comprises Ni (NO)3)2、NiCl2And NiSO4At least one of;
the molar ratio of the iron source to the nickel source to the isophthalic acid is (0.02-0.1): (0.02-0.1): (0.05-0.1);
the molar ratio of the cobalt source to the sulfur source is (0.02-0.15): (0.005-0.015);
the solvent of the first electrodeposition solution and/or the second electrodeposition solution is a mixed solvent of N, N-dimethylformamide and deionized water.
2. The method according to claim 1, wherein the molar ratio of the iron source, the nickel source and the isophthalic acid is (0.02-0.05): (0.02-0.05): (0.05-0.08).
3. The process according to claim 2, wherein the molar ratio of the iron source, the nickel source and the isophthalic acid is 0.03: 0.03: 0.075.
4. the process according to claim 1, characterized in that the molar ratio of the cobalt source and the sulfur source is (0.08-0.15): (0.008-0.012).
5. The process according to claim 4, characterized in that the molar ratio between the cobalt source and the sulphur source is 0.1: 0.01.
6. the method according to claim 1, wherein the volume ratio of the N, N-dimethylformamide to the deionized water is (1-2): 1.
7. the method of claim 1, wherein the second bath is obtained by:
dissolving the isophthalic acid in the N, N-dimethylformamide to obtain a first prefabricated liquid;
dissolving the iron source in the deionized water to obtain a second prefabricated liquid;
adding the second prefabricated liquid into the first prefabricated liquid, and stirring the obtained third prefabricated liquid;
adding the N, N-dimethylformamide into the third prefabricated liquid to obtain a fourth prefabricated liquid;
adding the nickel source to the fourth preformation liquor to obtain the second electrodeposition liquor.
8. The method of claim 1, further comprising, prior to placing the nickel foam into the first bath:
and carrying out acidification treatment on the foamed nickel.
9. The method of claim 8, wherein said acidifying of said nickel foam is performed by soaking said nickel foam in an acidic solution.
10. The method of claim 9, wherein the acidic solution comprises hydrochloric acid.
11. The method of claim 10, wherein the hydrochloric acid has a concentration of 2 to 4 mol/L.
12. The method according to claim 8, wherein the time of the acidification treatment is 20min to 40 min.
13. The method of claim 8, wherein the acidification is performed under ultrasound.
14. The method of claim 1, further comprising, prior to placing the preform in the second bath:
and putting the prefabricated object into a solution containing a surfactant for surface modification treatment.
15. The method of claim 14, wherein the surfactant comprises polyvinylpyrrolidone.
16. The method according to claim 14, wherein the concentration of the surfactant in the surfactant-containing solution is 0.015g/mL to 0.04 g/mL.
17. The method according to claim 14, wherein the surface modification treatment is performed for 6 to 10 hours.
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