Cobalt-containing polyacid-based ionic crystal electrocatalyst as well as preparation method and application thereof
By preparing a non-noble metal Al/Co-doped W polyacid-based porous ionic crystal nanocomposite catalyst, the problem of scarcity limitation of noble metal catalysts was solved, the efficiency of hydrogen production by water electrolysis was improved, and the overpotential of the anode reaction was reduced.
Patent Information
- Application Number
- CN202410714724.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-04
- Publication Date
- 2025-12-05
AI Technical Summary
In existing technologies, the scarcity of precious metal catalysts such as iridium and ruthenium oxides for the oxygen evolution reaction (OER) limits the improvement of hydrogen production efficiency through water electrolysis, and results in a large overpotential for the anode reaction.
A polyacid-based porous ionic crystal nanocomposite catalyst with non-precious metals Al/Co as the main elements and doped with W was developed. By synthesizing cobalt-containing polyacid ionic crystal nanocomposite materials, the performance of the catalyst in the electrolytic hydrogen production anode reaction under acidic conditions was improved.
It effectively reduced the overpotential of the anodic reaction, improved catalytic efficiency, reduced the amount of precious metals used, and lowered the preparation cost.
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Figure CN121065747A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of fuel cells, in particular to a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst and a preparation method and application thereof. BACKGROUND
[0002] Hydrogen (H2) is considered as the most promising secondary energy carrier to change the current energy structure dominated by fossil fuels, as a clean energy carrier with high energy density (120-142 MJ kg -1 Compared with traditional fossil fuel reforming, water electrolysis is considered as a renewable and environmentally friendly technology because of its high product purity and no pollution. Water electrolysis includes two half-reactions: anode oxygen evolution reaction (OER) and cathode hydrogen evolution reaction (HER), wherein the anode reaction involves four-electron transfer and has a slow kinetic process, resulting in a large anode overpotential. Therefore, developing efficient anode catalysts is very important for improving the overall efficiency of water electrolysis.
[0003] Currently, efficient anode catalysts are mainly iridium and ruthenium oxides. The scarcity of noble metals limits their widespread use. Therefore, it is very important to reduce the use of noble metal materials and improve the anode oxygen evolution efficiency for the popularization of water electrolysis technology. SUMMARY
[0004] The inventors found that among non-noble transition metal-based catalysts, polyoxometalate-based materials have excellent redox properties and electrochemical conductivity, and are very promising anode catalyst materials for water electrolysis. Moreover, polyoxometalates are stable under neutral to acidic conditions, and Co-containing polyoxometalates (Co-POMs) are particularly promising as OER electrocatalysts. In the polyoxometalate-based material system, the electronic redistribution characteristics of Co-containing polyoxometalates in the composite material can significantly improve the OER electrocatalytic activity. By synthesizing Co-containing polyoxometalate ionic crystal nanocomposites, potential electrocatalysts can be obtained and the acid OER performance of the material can be effectively improved.
[0005] The present application provides a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst and a preparation method and application thereof, to reduce the use of noble metals in the catalyst and improve the catalytic efficiency.
[0006] In a first aspect, the present application provides a preparation method of a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, which comprises:
[0007] reacting a cobalt source and a polyoxometalate to introduce cobalt into the polyoxometalate to obtain a precursor;
[0008] preparing an aluminum source into an Al 13 aqueous solution;
[0009] The precursor and the Al 13 The aqueous solution is mixed with a first solvent to react, so as to introduce Al 13 The precursor is introduced to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst.
[0010] As an optional embodiment, the cobalt source includes CoCl2.
[0011] As an optional embodiment, the polyoxometalate includes K8SiW 11 O 39 .
[0012] As an optional embodiment, the reaction of the cobalt source and the polyoxometalate to introduce cobalt into the polyoxometalate to obtain the precursor includes:
[0013] The polyoxometalate is dissolved in a second solvent to obtain a polyoxometalate solution;
[0014] The polyoxometalate solution and the cobalt source aqueous solution are mixed to react, and then a poor solvent is added to obtain the precursor.
[0015] As an optional embodiment, when the polyoxometalate is dissolved, the temperature of the second solvent is 70-90°C.
[0016] As an optional embodiment, the relationship between the polyoxometalate and the second solvent satisfies: 10-20 g of the polyoxometalate is dissolved in 100 mL of the second solvent.
[0017] As an optional embodiment, the molar concentration of the cobalt source aqueous solution is 1-3 mol / L.
[0018] As an optional embodiment, the volume ratio of the polyoxometalate solution to the cobalt source aqueous solution is 1-2:0.5-1.5.
[0019] As an optional embodiment, the poor solvent includes methanol.
[0020] As an optional embodiment, the aluminum source includes AlCl3.
[0021] As an optional embodiment, the aluminum source is prepared into an Al 13 The aqueous solution includes:
[0022] The sodium hydroxide aqueous solution is added dropwise into the aluminum source aqueous solution to obtain an Al 13 aqueous solution.
[0023] As an optional embodiment, the temperature of the aluminum source aqueous solution is 80-90°C.
[0024] As an optional embodiment, the temperature of the aluminum source aqueous solution is 83-87°C.
[0025] As an optional implementation, the molar concentration of the sodium hydroxide aqueous solution is 0.2-0.3 mol / L.
[0026] As an optional implementation, the volume ratio of the sodium hydroxide aqueous solution and the aluminum source aqueous solution is 8-10:3-5.
[0027] As an optional implementation, the mixing of the precursor and the Al 13 aqueous solution in the first solvent is to introduce Al 13 into the precursor to obtain the cobalt-containing polyacid-based ion crystal electrocatalyst.
[0028] The precursor is dissolved in the first solvent to obtain a precursor solution.
[0029] The precursor solution and the Al 13 aqueous solution are mixed to react, so as to introduce Al 13 into the precursor to obtain the cobalt-containing polyacid-based ion crystal electrocatalyst.
[0030] As an optional implementation, the relationship between the precursor and the first solvent satisfies that 4-7 g of the precursor is dissolved in 100 mL of the first solvent.
[0031] As an optional implementation, the volume ratio of the precursor solution and the Al 13 aqueous solution is 8-10:10-15.
[0032] In a second aspect, the application provides a cobalt-containing polyacid-based ion crystal electrocatalyst, which is obtained by the method of the first aspect.
[0033] In a third aspect, the application provides an application of a cobalt-containing polyacid-based ion crystal electrocatalyst, which is the catalyst of the second aspect, and the application includes applying the catalyst to the preparation of a fuel cell.
[0034] Compared with the prior art, the above technical solution provided in the embodiments of the application has the following advantages:
[0035] The method provided in the embodiments of the application introduces Al and Co into a polyacid doped with W elements to obtain a polyacid-based porous ion crystal nanocomposite catalyst prepared by taking non-noble metal Al / Co as main elements and doping W elements. The catalyst can effectively improve the anode reaction performance of the catalyst in electrolytic hydrogen production under acidic conditions, reduce the anode reaction overpotential, and achieve the purposes of reducing the use of noble metals of the catalyst and improving the catalytic efficiency. BRIEF DESCRIPTION OF DRAWINGS
[0036] The accompanying drawings, which are incorporated into and form a part of the specification, illustrate preferred embodiments of the present application and, together with the description, serve to explain the principles of the application.
[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those skilled in the art, based on the drawings, other drawings can be obtained without creative labor.
[0038] Figure 1 Flow chart of the method provided by the embodiments of the present application;
[0039] Figure 2 SXRD single crystal structure diagram of the catalyst provided by the embodiments of the present application;
[0040] Figure 3 PXRD powder X-ray diffraction diagram of the catalyst provided by the embodiments of the present application. DETAILED DESCRIPTION
[0041] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0042] Unless otherwise specifically indicated, the various materials, reagents, instruments and equipment and the like used in the present application can be purchased from the market or can be prepared by the existing method.
[0043] Electrolysis of water to produce hydrogen includes two half-reactions: anode oxygen evolution reaction (OER) and cathode hydrogen evolution reaction (HER), wherein the anode reaction involves four electron transfer and has a slow kinetic process, resulting in a large anode overpotential. Therefore, developing efficient anode catalysts is very important for improving the overall efficiency of water electrolysis reaction. Currently, efficient anode catalysts are mainly iridium and ruthenium oxides. The scarcity of noble metals limits their universal use. Therefore, reducing the use of noble metal materials and improving the anode oxygen evolution efficiency is very important for the popularization of water electrolysis hydrogen production technology.
[0044] The inventors found that polyoxometalates-based materials have excellent redox properties and electrochemical conductivity in non-noble transition metal-based catalysts, and are promising anode catalyst materials for hydrogen production by water electrolysis. Moreover, polyoxometalates are stable under neutral to acidic conditions, and Co-containing polyoxometalates (Co-POMs) are particularly promising as OER electrocatalysts. In polyoxometalate-based material systems, the electronic redistribution characteristics of Co-containing polyoxometalates in composite materials can significantly improve the electrocatalytic activity of OER. By synthesizing Co-containing polyoxometalate ionic crystal nanocomposite materials, potential electrocatalysts can be prepared to effectively improve the acidic OER performance of the materials.
[0045] The inventors intend to provide a method for preparing a polyoxometalate-based porous ionic crystal nanocomposite catalyst with non-noble metals Al / Co as main elements and doped with W elements.
[0046] Figure 1 As shown in the flowchart of the method provided in the embodiments of the present application, Figure 1 a preparation method of a Co-containing polyoxometalate-based ionic crystal electrocatalyst is provided, and the method comprises:
[0047] S1. reacting a cobalt source and a polyoxometalate to introduce cobalt into the polyoxometalate to obtain a precursor;
[0048] The polyoxometalate refers to a polyoxometalate, which is a nanoscale metal-oxygen cluster compound formed by high oxidation states of pre-transition metal ions (such as V, Mo, W, etc.) and oxygen. The cobalt source refers to a material capable of providing cobalt ions during the reaction.
[0049] In some embodiments, the cobalt source comprises CoCl2. The polyoxometalate comprises K8SiW 11 O 39 .
[0050] In some embodiments, the reaction of the cobalt source and the polyoxometalate to introduce cobalt into the polyoxometalate to obtain a precursor comprises:
[0051] S1.1. dissolving the polyoxometalate in a second solvent to obtain a polyoxometalate solution; the second solvent can specifically be selected from water.
[0052] In some embodiments, the relationship between the polyacid and the second solvent satisfies: 10-20 g of the polyacid is dissolved in 100 mL of the second solvent. Illustratively, the relationship between the polyacid and the second solvent can satisfy: 10 g of the polyacid is dissolved in 100 mL of the second solvent, 11 g of the polyacid is dissolved in 100 mL of the second solvent, 12 g of the polyacid is dissolved in 100 mL of the second solvent, 13 g of the polyacid is dissolved in 100 mL of the second solvent, 14 g of the polyacid is dissolved in 100 mL of the second solvent, 15 g of the polyacid is dissolved in 100 mL of the second solvent, 16 g of the polyacid is dissolved in 100 mL of the second solvent, 17 g of the polyacid is dissolved in 100 mL of the second solvent, 18 g of the polyacid is dissolved in 100 mL of the second solvent, 19 g of the polyacid is dissolved in 100 mL of the second solvent, or 20 g of the polyacid is dissolved in 100 mL of the second solvent, etc., which can also be any value within the range of 10-20 g of the polyacid dissolved in 100 mL of the second solvent.
[0053] S1.2. Mixing the polyacid solution and the cobalt source aqueous solution, and then adding the poor solvent to obtain a precursor.
[0054] In some embodiments, the molar concentration of the cobalt source aqueous solution is 1-3 mol / L. The volume ratio of the polyacid solution to the cobalt source aqueous solution is 1-2:0.5-1.5.
[0055] Illustratively, the molar concentration of the cobalt source aqueous solution can be: 1 mol / L, 1.2 mol / L, 1.4 mol / L, 1.6 mol / L, 1.8 mol / L, 2 mol / L, 2.2 mol / L, 2.4 mol / L, 2.6 mol / L, 2.8 mol / L, or 3 mol / L, etc., which can also be any value within the range of 1-3 mol / L. The volume ratio of the polyacid solution to the cobalt source aqueous solution is 1:0.5, 1.5:0.5, 2:0.5, 1:1, 1:1.5, 2:1, 2:1.5, or 1.5:1, etc., which can also be any value within the range of 1-2:0.5-1.5.
[0056] In some embodiments, the poor solvent includes methanol.
[0057] Specifically, in this embodiment, a certain proportion of polyacid K8SiW 11 O 39 is dissolved in 300 mL of 80°C aqueous solution, the above solution is slowly added to the CoCl2 aqueous solution and stirred vigorously for 1 hour. After standing at room temperature for 6 hours, an appropriate amount of methanol solution is added, and the precipitated polyacid K8CoW 11 CoO 39 is centrifuged, washed, and dried at 60°C for standby, to obtain a precursor
[0058] S2. Preparing an aluminum source into an Al 13 aqueous solution;
[0059] The aluminum source refers to a material capable of providing aluminum ions in the reaction process. In some embodiments, the aluminum source comprises AlCl3.
[0060] In some embodiments, the step of preparing an aluminum source into an Al 13 The aqueous solution comprises: adding an aqueous solution of sodium hydroxide into the aqueous solution of the aluminum source to obtain an Al 13 aqueous solution.
[0061] The temperature of the aqueous solution of the aluminum source is 80-90°C. Further, the temperature of the aqueous solution of the aluminum source is 83-87°C. The molar concentration of the aqueous solution of sodium hydroxide is 0.2-0.3 mol / L. The volume ratio of the aqueous solution of sodium hydroxide to the aqueous solution of the aluminum source is 8-10:3-5. Exemplarily, the temperature of the aqueous solution of the aluminum source can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C or 90°C, etc., which can also be any value in the range of 80-90°C. The molar concentration of the aqueous solution of sodium hydroxide can be 0.2 mol / L, 0.21 mol / L, 0.22 mol / L, 0.23 mol / L, 0.24 mol / L, 0.25 mol / L, 0.26 mol / L, 0.27 mol / L, 0.28 mol / L, 0.29 mol / L or 0.3 mol / L, etc., which can also be any value in the range of 0.2-0.3 mol / L.
[0062] Specifically, in this embodiment, a certain proportion of the aqueous solution of sodium hydroxide is added dropwise into the aqueous solution of AlCl3at a temperature of 85°C to obtain an Al 13 aqueous solution.
[0063] S3. Mixing the precursor and the Al 13 aqueous solution in a first solvent to react to introduce Al 13 into the precursor to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst.
[0064] In some embodiments, the step of mixing the precursor and the Al 13 aqueous solution in a first solvent to react to introduce Al 13 into the precursor to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst comprises:
[0065] S3.1. Dissolving the precursor in a first solvent to obtain a precursor solution;
[0066] In some embodiments, the precursor and the first solvent satisfy the relationship: 4-7 g of the precursor is dissolved in 100 mL of the first solvent. Exemplarily, the precursor and the first solvent can satisfy the relationship: 4 g of the precursor is dissolved in 100 mL of the first solvent, 4.5 g of the precursor is dissolved in 100 mL of the first solvent, 5 g of the precursor is dissolved in 100 mL of the first solvent, 5.5 g of the precursor is dissolved in 100 mL of the first solvent, 6 g of the precursor is dissolved in 100 mL of the first solvent, 6.5 g of the precursor is dissolved in 100 mL of the first solvent, or 7 g of the precursor is dissolved in 100 mL of the first solvent, which can also be any value within the range of 4-7 g of the precursor dissolved in 100 mL of the first solvent.
[0067] S3.2. Mixing the precursor solution and the Al 13 aqueous solution to carry out a mixing reaction to introduce Al 13 into the precursor, to obtain a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst.
[0068] In some embodiments, the volume ratio of the precursor solution and the Al 13 aqueous solution is 8-10:10-15. Exemplarily, the volume ratio of the precursor solution and the Al 13 aqueous solution can be 8:10, 9:10, 10:10, 8:11, 9:11, 10:11, 8:12, 9:12, 10:12, 8:13, 9:13, 10:13, 8:14, 9:14, 10:14, 8:15, 9:15, or 10:15, etc., which can also be any value within the range of 8-10:10-15.
[0069] Specifically, in the present embodiment, a certain amount of the precursor K8CoW 11 CoO 39 powder is uniformly dispersed in 100 mL of deionized water under continuous stirring after being ground with a mortar. A certain amount of the Al 13 aqueous solution is added to the precursor K8CoW 11 CoO 39 aqueous solution, and the mixture is allowed to stand. After 12 h, the blue precipitate, i.e., the Al13-CoW11Co polyoxometalate-based porous ionic crystal nanocomposite, is centrifuged, washed, and dried for standby, to obtain a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst.
[0070] The method introduces Al and Co into the polyacid doped with W elements to obtain a polyacid-based porous ion crystal nanocomposite catalyst mainly containing non-noble metal Al / Co and doped with W elements. The catalyst can effectively improve the anode reaction performance of the catalyst in electrolytic hydrogen production under acidic conditions, reduce the anode reaction overpotential, and reduce the use of noble metals of the catalyst and improve the catalytic efficiency.
[0071] As shown in Figure 2 and Figure 3 , based on one general inventive concept, the embodiments of the present application also provide a cobalt-containing polyacid-based ion crystal electrocatalyst, which is prepared by the method of the first aspect.
[0072] The catalyst is prepared based on the above method. The specific steps of the method can refer to the above embodiments. Since the catalyst uses part or all of the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.
[0073] Based on one general inventive concept, the embodiments of the present application also provide an application of a cobalt-containing polyacid-based ion crystal electrocatalyst. The catalyst is the catalyst of the second aspect, and the application includes applying the catalyst to the preparation of a fuel cell.
[0074] The present application will be further described in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present application and not to limit the scope of the present application. The experimental methods in the following examples are not specified, and generally according to the national standard. If there is no corresponding national standard, it is carried out according to the general international standard, the conventional condition, or the condition suggested by the manufacturer.
[0075] Example 1
[0076] A preparation method of a cobalt-containing polyacid-based ion crystal electrocatalyst, the method comprising:
[0077] 1. Synthesis of precursor K8CoW 11 CoO 39 : 50 g of polyacid K8SiW 11 O 39 is dissolved in 300 mL of deionized water, and the above solution is slowly added to 100 mL of 2 mol / L CoCl2 aqueous solution and stirred vigorously for 1 hour. After standing at room temperature for 6 hours, 100 mL of methanol solution is added, and the precipitated precursor K8CoW 11 CoO 39 is centrifuged, washed, and dried at 60°C for standby;
[0078] 2. Al 13Synthesis of aqueous solution: At 85℃, 450 mL of 0.25 mol / L sodium hydroxide aqueous solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution to obtain Al 13 Aqueous solution;
[0079] 3. Take 5g of the precursor K8CoW 11 CoO 39 The powder was ground in a mortar and pestle and then evenly dispersed in 100 mL of deionized water with continuous stirring to obtain a precursor solution.
[0080] 4. Add 100mL Al 13 An aqueous solution was added to the precursor solution, and after standing for 12 hours, the blue precipitate, namely Al13-CoW11Co polyacid-based porous ionic crystal nanocomposite material, was centrifuged, washed, and dried to obtain the catalyst.
[0081] Example 2
[0082] A method for preparing a cobalt-containing polyacid-based ionic crystal electrocatalyst, the method comprising:
[0083] 1. Precursor K8CoW 11 CoO 39 Synthesis: Weigh 50g of polyacid K8SiW 11 O 39 Dissolve the precursor K8CoW in 300 mL of deionized water. Slowly add the above solution to 100 mL of 2 mol / L CoCl2 aqueous solution and stir vigorously for 1 hour. After standing at room temperature for 6 hours, add 100 mL of methanol solution to precipitate the precursor K8CoW. 11 CoO 39 Centrifuge, wash, and dry at 60℃ for later use;
[0084] 2.Al 13 Synthesis of aqueous solution: At 85℃, 450 mL of 0.25 mol / L sodium hydroxide aqueous solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution to obtain Al 13 Aqueous solution;
[0085] 3. Take 5g of the precursor K8CoW 11 CoO 39 The powder was ground in a mortar and pestle and then evenly dispersed in 80 mL of deionized water with continuous stirring to obtain a precursor solution.
[0086] 4. Add 100mL Al 13 An aqueous solution was added to the precursor solution, and after standing for 12 hours, the blue precipitate, namely Al13-CoW11Co polyacid-based porous ionic crystal nanocomposite material, was centrifuged, washed, and dried to obtain the catalyst.
[0087] Example 3
[0088] A method for preparing a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, the method comprising:
[0089] 1. Synthesis of precursor K8CoW 11 CoO 39 : 50 g of polyoxometalate K8SiW 11 O 39 was dissolved in 300 mL of deionized water, and the above solution was slowly added to 100 mL of a 2 mol / L CoCl2 aqueous solution and stirred vigorously for 1 hour. After standing at room temperature for 6 h, 100 mL of a methanol solution was added, and the precipitated precursor K8CoW 11 CoO 39 was centrifuged, washed, and dried at 60°C for standby use;
[0090] 2. Synthesis of Al 13 aqueous solution: 450 mL of a 0.25 mol / L sodium hydroxide aqueous solution was added dropwise to 200 mL of a 0.25 mol / L AlCl3 aqueous solution at a temperature of 85°C to obtain an Al 13 aqueous solution;
[0091] 3. 5 g of the precursor K8CoW 11 CoO 39 powder was ground using a mortar and then uniformly dispersed in 80 mL of deionized water with constant stirring to obtain a precursor solution.
[0092] 4. 150 mL of the Al 13 aqueous solution was added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e., an Al13-CoW11Co polyoxometalate-based porous ionic crystal nanocomposite material, was centrifuged, washed, and dried to obtain a catalyst.
[0093] Example 4
[0094] A method for preparing a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, the method comprising:
[0095] 1. Synthesis of precursor K8CoW 11 CoO 39 : 50 g of polyoxometalate K8SiW 11 O 39 was dissolved in 300 mL of deionized water, and the above solution was slowly added to 100 mL of a 2 mol / L CoCl2 aqueous solution and stirred vigorously for 1 hour. After standing at room temperature for 6 h, 100 mL of a methanol solution was added, and the precipitated precursor K8CoW 11 CoO 39 was centrifuged, washed, and dried at 60°C for standby use;
[0096] 2. Al 13 Synthesis of aqueous solution: 450 mL of 0.25 mol / L aqueous sodium hydroxide solution was added dropwise into 200 mL of 0.25 mol / L aqueous AlCl3 solution at a temperature of 85°C to obtain an aqueous Al 13 solution;
[0097] 3. 5 g of the precursor K8CoW 11 CoO 39 powder was uniformly dispersed in 80 mL of deionized water under constant stirring after being ground with a mortar to obtain a precursor solution.
[0098] 4. 130 mL of aqueous Al 13 solution was added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e., the Al13-CoW11Co polyoxometallate-based porous ionic crystal nanocomposite material, was centrifuged, washed, and dried to obtain a catalyst.
[0099] Example 5
[0100] A method for preparing a cobalt-containing polyoxometallate-based ionic crystal electrocatalyst, the method comprising:
[0101] 1. Synthesis of the precursor K8CoW 11 CoO 39 50 g of the polyoxometallate K8SiW 11 O 39 was dissolved in 300 mL of deionized water, and the above solution was slowly added to 100 mL of 2 mol / L aqueous CoCl2 solution and stirred vigorously for 1 h. After standing at room temperature for 6 h, 100 mL of a methanol solution was added, and the precipitated precursor K8CoW 11 CoO 39 was centrifuged, washed, and dried at 60°C for standby use;
[0102] 2. Synthesis of aqueous Al 13 solution: 450 mL of 0.25 mol / L aqueous sodium hydroxide solution was added dropwise into 200 mL of 0.25 mol / L aqueous AlCl3 solution at a temperature of 85°C to obtain an aqueous Al 13 solution;
[0103] 3. 5 g of the precursor K8CoW 11 CoO 39 powder was uniformly dispersed in 80 mL of deionized water under constant stirring after being ground with a mortar to obtain a precursor solution.
[0104] 4. 120 mL of aqueous Al 13The aqueous solution is added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e. the Al13-CoW11Co polyoxometallate-based porous ionic crystal nanocomposite material, is centrifuged, washed, dried, and the catalyst is obtained.
[0105] Example 6
[0106] A preparation method of a cobalt-containing polyoxometallate-based ionic crystal electrocatalyst, the method comprising:
[0107] 1. Synthesis of the precursor K4SiW 11 Synthesis of PtO39: 50 g of the polyoxometallate K8SiW 11 O 39 is dissolved in 300 mL of deionized water, and the above solution is slowly added to 100 mL of a 2 mol / L CoCl2aqueous solution and stirred vigorously for 1 h. After standing at room temperature for 6 h, 100 mL of a methanol solution is added, and the precipitated precursor K8CoW 11 CoO 39 is centrifuged, washed, and dried at 60°C for standby use.
[0108] 2. Synthesis of the aqueous solution of Al 13 The aqueous solution is synthesized by dropwise adding 450 mL of a 0.25 mol / L sodium hydroxide aqueous solution to 200 mL of a 0.25 mol / L AlCl3aqueous solution at a temperature of 85°C to obtain Al 13 aqueous solution.
[0109] 3. 5 g of the precursor K8CoW 11 CoO 39 powder is ground with a mortar and uniformly dispersed in 80 mL of deionized water under constant stirring to obtain a precursor solution.
[0110] 4. 110 mL of the Al 13 aqueous solution is added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e. the Al13-CoW11Co polyoxometallate-based porous ionic crystal nanocomposite material, is centrifuged, washed, dried, and the catalyst is obtained.
[0111] Example 7
[0112] A preparation method of a cobalt-containing polyoxometallate-based ionic crystal electrocatalyst, the method comprising:
[0113] 1. Synthesis of the precursor K8CoW 11 CoO 39 : 50 g of the polyoxometallate K8SiW 11 O 39CoW11Co polyoxometalate-based porous ionic crystal nanocomposite material, centrifugal, washing, drying to obtain the catalyst. 11 CoO 39 Centrifugal, washing, drying at 60°C for standby;
[0114] 2. Al 13 Aqueous solution synthesis: 450 mL of 0.25 mol / L aqueous sodium hydroxide solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution at a temperature of 85°C to obtain Al 13 Aqueous solution;
[0115] 3. Take 5g of precursor K8CoW 11 CoO 39 Powder, after grinding with a mortar, evenly dispersed in 80 mL of deionized water under constant stirring to obtain a precursor solution.
[0116] 4. Add 140 mL of Al 13 Aqueous solution to the precursor solution, after standing for 12h, centrifugal, washing, drying the blue precipitate, namely Al13-CoW11Co polyoxometalate-based porous ionic crystal nanocomposite material, to obtain the catalyst.
[0117] Example 8
[0118] A method for preparing a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, the method comprising:
[0119] 1. Synthesis of precursor K8CoW 11 CoO 39 : Take 50g of polyoxometalate K8SiW 11 O 39 Dissolved in 300 mL of deionized water, slowly add the above solution to 100 mL of 2 mol / L CoCl2 aqueous solution and stir vigorously for 1 hour. After standing at room temperature for 6h, add 100 mL of methanol solution, centrifugal, washing, drying at 60°C for standby; 11 CoO 39 Centrifugal, washing, drying at 60°C for standby;
[0120] 2. Al 13 Aqueous solution synthesis: 450 mL of 0.25 mol / L aqueous sodium hydroxide solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution at a temperature of 85°C to obtain Al 13 Aqueous solution;
[0121] 3. Take 5g of precursor K8CoW 11 CoO39 The powder, after being ground with a mortar, was uniformly dispersed into 85 mL of deionized water under constant stirring to obtain a precursor solution.
[0122] 4. 100 mL of an Al 13 aqueous solution was added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e., an Al13-CoW11Co polyoxometallate-based porous ionoceramic nanocomposite, was centrifuged, washed, and dried to obtain a catalyst.
[0123] Example 9
[0124] A method for preparing a cobalt-containing polyoxometallate-based ionoceramic electrocatalyst, the method comprising:
[0125] 1. Synthesis of a precursor K8CoW 11 CoO 39 50 g of a polyoxometallate K8SiW 11 O 39 was dissolved in 300 mL of deionized water, and the above solution was slowly added to 100 mL of a 2 mol / L CoCl2 aqueous solution and stirred vigorously for 1 h. After standing at room temperature for 6 h, 100 mL of a methanol solution was added, and the precipitated precursor K8CoW 11 CoO 39 was centrifuged, washed, and dried at 60°C for standby use;
[0126] 2. Synthesis of an Al 13 aqueous solution: 450 mL of a 0.25 mol / L NaOH aqueous solution was added dropwise to 200 mL of a 0.25 mol / L AlCl3 aqueous solution at a temperature of 85°C to obtain an Al 13 aqueous solution;
[0127] 3. 5 g of the precursor K8CoW 11 CoO 39 powder, after being ground with a mortar, was uniformly dispersed into 90 mL of deionized water under constant stirring to obtain a precursor solution.
[0128] 4. 100 mL of an Al 13 aqueous solution was added to the precursor solution, and after standing for 12 h, the blue precipitate, i.e., an Al13-CoW11Co polyoxometallate-based porous ionoceramic nanocomposite, was centrifuged, washed, and dried to obtain a catalyst.
[0129] Example 10
[0130] A method for preparing a cobalt-containing polyoxometallate-based ionoceramic electrocatalyst, the method comprising:
[0131] 1. Synthesis of a precursor K8CoW 11 CoO 39Synthesis: Weigh 50g of polyacid K8SiW 11 O 39 Dissolve the above solution in 300 mL of deionized water, then slowly add the solution to 100 mL of 2 mol / L CoCl2 aqueous solution and stir vigorously for 1 hour. After standing at room temperature for 6 hours, add 100 mL of methanol solution to precipitate the precursor K8CoW. 11 CoO 39 Centrifuge, wash, and dry at 60℃ for later use;
[0132] 2.Al 13 Synthesis of aqueous solution: At 85℃, 450 mL of 0.25 mol / L sodium hydroxide aqueous solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution to obtain Al 13 Aqueous solution;
[0133] 3. Take 5g of the precursor K8CoW 11 CoO 39 The powder was ground in a mortar and pestle and then evenly dispersed in 95 mL of deionized water with continuous stirring to obtain a precursor solution.
[0134] 4. Add 100mL Al 13 An aqueous solution was added to the precursor solution, and after standing for 12 hours, the blue precipitate, namely Al13-CoW11Co polyacid-based porous ionic crystal nanocomposite material, was centrifuged, washed, and dried to obtain the catalyst.
[0135] Comparative Example 1
[0136] A method for preparing a platinum-containing polyacid-based ionic crystal electrocatalyst, the method comprising:
[0137] 1. Synthesis of precursor K8SiW11O39: Weigh 5g of polyacid K8SiW11O39... 11 O 39 Dissolve the above solution in 300 mL of deionized water, then slowly add the solution to 100 mL of 0.2 mol / L PtCl2 aqueous solution and stir vigorously for 1 hour. After standing at room temperature for 6 hours, add 100 mL of methanol solution to precipitate the precursor K4SiW. 11 PtO 39 Centrifuge, wash, and dry at 60℃ for later use;
[0138] 2.Al 13 Synthesis of aqueous solution: At 85℃, 450 mL of 0.25 mol / L sodium hydroxide aqueous solution was added dropwise to 200 mL of 0.25 mol / L AlCl3 aqueous solution to obtain Al 13 Aqueous solution;
[0139] 3. Take 5g of the precursor K4SiW11 PtO 39 The powder was ground in a mortar and pestle and then evenly dispersed in 80 mL of deionized water with continuous stirring to obtain a precursor solution.
[0140] 4. Add 140mL of Al 13 An aqueous solution was added to the precursor solution, and after standing for 12 hours, the blue precipitate, namely Al, was obtained. 13 -SiW 11 PtO 39 A catalyst was obtained by centrifuging, washing, and drying a polyacid-based porous ionic crystal nanocomposite material.
[0141] The catalysts provided in Examples 1-10 and Comparative Examples 1-x were tested, and the results are shown in the table below:
[0142]
[0143]
[0144] As can be seen from the data in the table above, the catalyst prepared by the method provided in the embodiments of this application has high catalytic activity and does not introduce precious metals, thus effectively controlling the preparation cost.
[0145] Appendix Figures 2 to 3 Detailed analysis
[0146] like Figure 2 As shown, Figure 2 The SXRD single crystal structure diagram of the catalyst provided in the embodiments of this application is shown in the figure. As can be seen from the figure, the catalyst Al... 13 -CoW11Co has a nanoscale porous structure.
[0147] like Figure 3 As shown, Figure 3 The PXRD powder X-ray diffraction pattern of the catalyst provided in the embodiments of this application shows that the method provided in the embodiments of this application can effectively prepare high-purity polyacid-based porous ionic crystal nanocomposite material Al. 13 -CoW11Co.
[0148] Various embodiments of the application can exist in a variety of forms; it should be understood that the description of the embodiments as being in a specific form is merely for convenience and brevity and should not be construed to limit the scope of the application; therefore, the description of a specific form should be considered to have specifically disclosed all possible sub-forms and individual numbers within the range. For example, it should be considered that the description of a range from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as individual numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. In addition, whenever a numerical range is indicated in this document, it refers to any cited number (fraction or integer) within the indicated range.
[0149] In this document, the positional words such as "upper" and "lower" are specifically the directions of the drawing surface in the drawings, unless otherwise stated. In addition, in the description of the specification, the terms "include", "contain", and the like mean "include but are not limited to". In this document, relational terms such as "first" and "second" and the like are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this document, "and / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can represent the cases where A exists alone, A and B exist together, and B exists alone. Where A and B can be singular or plural. In this document, "one or more" means one or more, and "multiple" means two or more. "At least one", "at least one of the following", or the like means any combination of the items, including single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can mean a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.
[0150] The above description is only a specific embodiment of the application, enabling those skilled in the art to understand or implement the application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application should not be limited to the embodiments shown herein, but should be consistent with the widest scope of the principles and novel features applied herein.
Claims
1. A method for preparing a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, characterized by, The method comprises: reacting a cobalt source and a polyacid to introduce cobalt into the polyacid to obtain a precursor; The aluminum source was prepared as Al 13 aqueous solution; The precursor and the Al 13 The aqueous solution is mixed with the first solvent to react to form the Al 13 The precursor is introduced to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst.
2. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 1, characterized in that, the cobalt source comprises CoCl2.
3. The method of claim 1, wherein the method is characterized by: The polyacid includes K8SiW 11 O 39 .
4. The method of claim 1, wherein the method is characterized by: The reaction of the cobalt source and the polyacid to introduce cobalt into the polyacid to obtain a precursor comprises: dissolving the polyacid in a second solvent to obtain a polyacid solution; mixing the polyacid solution and an aqueous cobalt source solution, and then adding a poor solvent to obtain the precursor.
5. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 4, characterized in that, During the dissolving, the temperature of the second solvent is 70-90℃.
6. The method of claim 4, wherein the method is characterized by: The relationship between the polyacid and the second solvent satisfies: 10-20g of the polyacid is dissolved in 100mL of the second solvent.
7. The method of claim 4, wherein the method is characterized by: The molar concentration of the aqueous cobalt source solution is 1-3mol / L.
8. The method of claim 4, wherein the method is characterized by: The volume ratio of the polyacid solution to the aqueous cobalt source solution is 1-2:0.5-1.
5.
9. The method of claim 4, wherein the method is characterized by: The poor solvent comprises methanol.
10. The method of claim 1, wherein the method is characterized by: The aluminum source comprises AlCl3.
11. The method of claim 1, wherein the method is characterized by: The aluminum source is formulated as Al 13 The aqueous solution comprises: An aqueous sodium hydroxide solution is added dropwise to the aqueous aluminum source solution to obtain Al(OH)3 13 aqueous solution.
12. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 11, characterized in that, The temperature of the aqueous aluminum source solution is 80-90℃.
13. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 12, characterized in that, The temperature of the aqueous aluminum source solution is 83-87℃.
14. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 11, characterized in that, The molar concentration of the aqueous sodium hydroxide solution is 0.2-0.3mol / L.
15. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 11, characterized in that, The volume ratio of the aqueous sodium hydroxide solution to the aqueous aluminum source solution is 8-10:3-5.
16. The method of claim 1, wherein the method is characterized by: said precursor and said Al 13 The aqueous solution is mixed with a first solvent to react with Al 13 The precursor is introduced to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst, which comprises: dissolving the precursor in a first solvent to obtain a precursor solution; The precursor solution and the Al 13 aqueous solution are mixed to react to form Al 13 The precursor is introduced to obtain a cobalt-containing polyoxometalate-based ion crystal electrocatalyst.
17. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 16, characterized in that, The relationship between the precursor and the first solvent satisfies: 4-7g of the precursor is dissolved in 100mL of the first solvent.
18. The method for preparing the cobalt-containing polyacid-based ionic crystal electrocatalyst according to claim 16, characterized in that, The precursor solution and the Al 13 The volume ratio of the aqueous solution is 8-10:10-15.
19. A cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, characterized in that, The catalyst is prepared by the method of any one of claims 1-18.
20. Use of a cobalt-containing polyoxometalate-based ionic crystal electrocatalyst, characterized in that The catalyst is the catalyst of claim 19, and the application comprises applying the catalyst to the preparation of a fuel cell.