Ir-Co3O4V (Co) nanosheet as well as preparation method and application thereof
By doping high-valent Ir ions in Co3O4, the problem of difficulty in balancing stability and activity of Ir-based catalysts in PEMWE is solved, and the high activity and long-term stable operation of the catalyst are achieved.
Patent Information
- Application Number
- CN202510263296.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-06
- Publication Date
- 2025-06-06
AI Technical Summary
The existing Ir-based catalysts have problems in PEMWE that the Ir content is high and the stability and activity are difficult to balance. Especially in acidic environments, high specific surface area materials are prone to decrease in stability due to Ir dissolution or agglomeration.
By doping high-valent Ir ions in Co3O4 containing Co vacancies, Ir-Co3O4V (Co) nanosheets were prepared by hydrothermal method and cation exchange method. The introduction of Ir significantly improved the activity and stability of the catalyst.
The initial potential of the catalyst during the OER process is increased, the reconstruction of Co3O4 is suppressed, the stability of the catalyst is significantly improved, and it can operate stably for more than 600 hours at a current density of 10mA/cm2.
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Figure CN120099554A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of preparation and application of new clean renewable energy, and specifically relates to an Ir-Co 3 O 4 V (Co) Nanosheets and preparation methods and applications thereof. Background Art
[0002] Excessive use of fossil fuels will exacerbate energy crises and environmental problems, so the development and utilization of renewable energy has become urgent. However, due to the intermittent nature of renewable energy such as solar energy, wind energy, tidal energy, etc., and the fact that my country's renewable energy is mainly distributed in the west, while electricity demand is mainly distributed in the southeast coast, we urgently need advanced energy conversion and storage solutions. Hydrogen has the characteristics of high energy density and carbon-free, and is an excellent energy carrier.
[0003] PEMWE hydrogen production has the advantages of long operating life, fast response speed, high hydrogen purity, low hydrogen production energy consumption and small footprint, and can achieve good coordination with renewable energy. However, in the acidic water splitting anode half-reaction, OER is a four-electron transfer process with slow reaction kinetics, requiring a higher potential to drive the reaction, and anode kinetic losses account for the largest proportion of the overall energy consumption. Moreover, the anode of PEMWE is a strongly acidic and highly oxidizing environment, and only a few precious metal-based catalysts can maintain reasonable catalytic activity and stability in such a working environment. At present, truly commercial anode catalysts are mainly Ir-based catalysts, but the high price and scarcity of Ir have become the main obstacles to the commercial application of PEMWE. And bulk IrO 2 The specific activity is low (<50 A / g Ir), and the activity needs to be improved through nanostructure design (such as Ir nanowires and core-shell structures). However, high specific surface area materials are easily destabilized due to Ir dissolution or agglomeration. Summary of the invention
[0004] In view of the problem that the Ir content in the Ir-based catalyst in the prior art is high and the stability and activity are difficult to balance, the present invention provides an Ir-Co 3 O 4 V (Co) Nanosheets and preparation methods and applications thereof. Through hydrothermal method and cation exchange method, Co containing Co vacancies 3 O 4 The introduction of Ir significantly improves the activity and stability of the catalyst. After the activity of the catalyst is improved, the starting potential of OER is higher than that of cobalt from Co Ⅲ / Co Ⅳ Transformed into Co Ⅳ / Co Ⅳ The required oxidation potential is lower, which inhibits the Co 3 O4 The reconstruction of Ir single atom substitution for Co 3 O 4 After the addition of some Co ions, Ir exists in a high valence state of +4.1. The formation of this high valence state may be achieved by optimizing the electronic structure and surface reaction sites to form Ir-Co 3 O 4 V (Co) The key mechanism of the nanosheets showing ultra-high activity in OER tests. 3 O 4 Nanosheets doped with high-valent Ir single atoms at 10 mA / cm 2 The overpotential is 245mV and at 10mA / cm 2 The current density can be stably operated for more than 600 hours.
[0005] One of the technical solutions of the present invention is to provide an Ir-Co 3 O 4 V (Co) Nanosheets, Ir single atoms and clusters supported on Co 3 O 4 V (Co) The nanosheets have an average size of 100 nm; the Ir-Co 3 O 4 V (Co) In the nanosheets, the Ir content is 2 to 10 wt%.
[0006] Ir single atoms are loaded on Co containing Co vacancies. 3 O 4 On the substrate, Co vacancies not only improve the conductivity of the substrate, but also change the Co 3 O 4 The local electronic environment of Ir atoms causes the d-band center position of Ir atoms to shift, and also promotes the electrons from Co 3 O 4 The carrier is transferred to the Ir single atom, making Ir in a more active oxidation state. This makes the adsorption strength of Ir single atoms to oxygen-containing intermediates (such as O*, OOH*) moderate, reduces the reaction energy barrier, and thus improves the OER kinetics. However, a major drawback of metal vacancies is that it will lead to a decrease in substrate stability, but the presence of Co vacancies allows the introduction of abundant Ir single atoms without agglomeration. These highly active Ir single atoms make the starting potential of OER higher than that of cobalt from Co. Ⅲ / Co Ⅳ Transformed into Co Ⅳ / Co Ⅳ The required oxidation potential is lower, which inhibits the Co 3 O 4The reconstruction significantly improves the stability of the catalyst. Ir single atoms can inhibit the dissolution of Co atoms nearby, so the rich Ir single atoms have a great influence on the Co 3 O 4 The substrate forms a pinning effect. In addition, the Co vacancies fix Ir single atoms through strong metal-support interaction (SMSI), reducing dissolution or migration under acidic conditions. This mutual stabilization mechanism makes the catalyst have excellent stability. Therefore, the catalyst is applied in the PEMWE anode to obtain the best stability in the single atom field.
[0007] The second technical solution of the present invention is to provide the above-mentioned Ir-Co 3 O 4 V (Co) The preparation method of the nanosheets comprises the following specific steps:
[0008] (1) 1.0 g C 4 H 6 CoO 4 ·4H 2 O was added to 30 ml C 3 H 8 O 3 After stirring and ultrasonication, a uniform slurry is obtained, and the slurry is subjected to a hydrothermal reaction at 180°C. Then, the obtained viscous mixture is repeatedly washed with ethanol and dried to obtain glycerol cobalt powder;
[0009] (2) Add 50 mg of glycerol cobalt to 50 ml of ethanol, ultrasonicate and stir; then, dropwise add 5-15 mg of IrCl 3 ·3H 2 O solution, and then heated in an oil bath at 80 °C; the product was collected by centrifugation, washed three times with ultrapure water and ethanol, and dried to obtain Ir-doped glycerol cobalt;
[0010] (3) The prepared powder was calcined at 350 °C to obtain Ir-Co 3 O 4 V (Co) powder.
[0011] Among them C 3 H 8 O 3 As a reducing agent, C 4 H 6 CoO 4 ·4H 2 O provides Co source, and then synthesizes glycerol cobalt powder after hydrothermal reaction, and then undergoes simple oil bath immersion treatment to finally form Ir-doped glycerol cobalt powder, which is then calcined in a muffle furnace to obtain Ir-Co 3 O 4 V (Co) Nanosheets.
[0012] Furthermore, the drying temperature in step 1 is 60°C.
[0013] Furthermore, the drying method in step 3 is drying in an oven at 60°C for 10 h.
[0014] Furthermore, the calcination time in step 4 is 12 hours.
[0015] The third technical solution of the present invention is to provide the above-mentioned Ir-Co 3 O 4 V (Co) Nanosheets are used as anodes for hydrogen production in proton exchange membrane water electrolysis (PEMWE). 3 O 4 V (Co) The nanosheet was used as the working electrode, the platinum sheet was used as the counter electrode, and 0.5 MH 2 SO 4 The solution was used as an electrolyte solution and exhibited good acidic OER activity and stability.
[0016] The beneficial effects of the present invention are:
[0017] (1) Ir-Co disclosed in the present invention 3 O 4 V (Co) Nanosheets, highly active Ir doped with Co in the form of single atoms and clusters 3 O 4 V (Co) In the catalyst, a small amount of Ir is used to expose a large number of active sites, which greatly improves the performance of the catalyst, thereby making the starting potential of OER higher than that of Co from Co. Ⅲ / Co Ⅳ Transformed into Co Ⅳ / Co Ⅳ The required oxidation potential is lower, which inhibits the increase of Co valence and Co 3 O 4 The reconstruction significantly improves the stability of the catalyst.
[0018] (2) The present invention adopts a simple hydrothermal-impregnation synthesis method to achieve preparation, providing an Ir-Co 3 O 4 V (Co) Synthesis method of nanosheets.
[0019] (3) Ir-Co disclosed in the present invention 3 O 4 V (Co)Nanosheet electrocatalytic oxygen evolution materials show excellent performance. In PEMWE, only 1.67V voltage is required to reach 1A / cm 2 The current density can reach 1000mA / cm 2 It operates stably at a current density of 2.5 Å, which fully demonstrates its excellent stability and efficient electrocatalytic activity. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 is the XRD diagram of Example 1, Comparative Example 1, Comparative Example 2 and Comparative Example 3;
[0021] Figure 2 is a topographical diagram of Example 1;
[0022] in, Figure 2 a and 2b are Ir-Co 3 O 4 V (Co) Transmission electron microscopy image of nanosheets after OER reaction. Figure 2 c and 2d are EDS images;
[0023] Figure 3 The catalyst of Example 1 and the catalyst of Comparative Examples 1, 2, 3 and commercial IrO 2 Catalyst performance comparison chart;
[0024] Figure 4 The catalyst of Example 1 and the catalyst of Comparative Examples 1, 2, 3 and commercial IrO 2 Comparison chart of catalyst stability;
[0025] Figure 5 The catalyst of Example 1 and the catalyst of Comparative Examples 1, 2, 3 and commercial IrO 2 Tafel plot of catalyst comparison;
[0026] Figure 6 The catalyst of Example 1 and the catalyst of Comparative Examples 1, 2, 3 and commercial IrO 2 CV diagram of the catalyst;
[0027] Figure 7 The catalyst of Example 1 and the catalyst of Comparative Examples 1, 2, 3 and commercial IrO 2 Comparative mass activity diagrams of catalysts;
[0028] Figure 8 Example 1 in PEMWE at 80°C, 500 mA / cm 2 ~1000mA / cm 2 The stability test data below. DETAILED DESCRIPTION
[0029] The following examples are used to further illustrate the present invention, and their purpose is to illustrate the present invention and should not be construed as limiting the scope of the present invention. Unless otherwise specified, all parts by weight and weight percentages are used below.
[0030] The raw materials used in the present invention, unless otherwise specified, are conventional commercially available products; the methods used in the present invention, unless otherwise specified, are conventional methods in the art.
[0031] The embodiments of the present invention are further described below with reference to a plurality of embodiments.
[0032] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0033] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.
[0034] Example 1
[0035] (1) Weigh 1.0 g C 4 H 6 CoO 4 ·4H 2 O was added to 30 ml C 3 H 8 O 3 After stirring and ultrasonication, a uniform slurry was obtained. The slurry was poured into a 50 mL polytetrafluoroethylene-lined autoclave, and the reactor was heated to 180°C for hydrothermal reaction. Then, the obtained viscous mixture was repeatedly washed with ethanol and dried at 60°C. Glycerol cobalt powder was obtained.
[0036] (2) Weigh 50 mg of glycerol cobalt and add it to 50 ml of ethanol. Ultrasonicate and stir until the solution becomes turbid. Then, dropwise add 10 mg of IrCl 3 ·3H 2 O solution, and then heated in an oil bath at 80 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h.
[0037] (3) Pour the prepared powder into a crucible and place it in a muffle furnace and calcine it at 350°C to obtain Ir-Co 3 O 4 V (Co) powder.
[0038] The average size of the obtained catalyst was 100 nm and the Ir content was about 5.9 wt%. Figure 2 The scanning electron microscopy and transmission electron microscopy shown in the figure show that Ir is doped into Co 3 O 4 V (Co) The successful synthesis of this structure of nanosheets. Figure 2 a and 2b are Ir-Co 3 O 4 V (Co) Transmission electron microscopy image of nanosheets after OER reaction. Figure 2 c and 2d are EDS images; STEM images show Co 3 O 4 The Ir on the surface mainly exists in the form of single atoms, and the distance between single atoms is small. At the same time, some Ir is also observed to exist in the form of clusters. 3 O 4 V (Co) After the OER test, the Ir and O elements are still evenly distributed, indicating that there is no obvious phase segregation at the active site after the test process. The catalytic activity and stability of this cation-rich defect structure in the electrocatalytic process far exceeds that of the comparative material Ir-Co without obvious defects. 3 O 4 Nanosheets and other example materials. Figure 1 As shown, the diffraction peaks are consistent with the typical cubic Co 3 O 4 There is no characteristic peak attributed to Ir in the diffraction pattern. 3 O 4 After the introduction of Ir, the crystal structure did not change significantly, and the diffraction peak shifted to the left, indicating that part of Ir may be doped into Co. 3 O 4 The crystal lattice expands. 3 O 4 V (Co) The catalytic activity was excellent at a current density of 10 mA cm-2 with an overpotential of 245 mV.
[0039] Figure 8 The nanosheets in this example are in PEMWE at 80°C and 500 mA / cm 2 ~1000mA / cm 2 Stability test data under the following conditions; only 1.67V voltage is required to reach 1A / cm 2 The current density can reach 500mA / cm 2 ~1000mA / cm 2It can operate stably for up to 3000 h at a current density of 1.547 W / m, fully demonstrating its excellent stability and efficient electrocatalytic activity.
[0040] Example 2
[0041] (1) Weigh 1.0 g C 4 H 6 CoO 4 ·4H 2 O was added to 30 ml C 3 H 8 O 3 After stirring and ultrasonication, a uniform slurry was obtained. The slurry was poured into a 50 mL polytetrafluoroethylene-lined autoclave, and the reactor was heated to 180°C for hydrothermal reaction. Then, the obtained viscous mixture was repeatedly washed with ethanol and dried at 60°C. Glycerol cobalt powder was obtained.
[0042] (2) Weigh 50 mg of glycerol cobalt and add it to 50 ml of ethanol. Ultrasonicate and stir until the solution becomes turbid. Then, dropwise add 5 mg of IrCl 3 ·3H 2 O solution, and then heated in an oil bath at 80 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h.
[0043] (3) Pour the prepared powder into a crucible and place it in a muffle furnace and calcine it at 350°C to obtain Ir-Co 3 O 4 V (Co) Powder. The obtained Ir-Co 3 O 4 V (Co) The content is 2wt%.
[0044] The catalyst prepared in this example was used as the anode. 2 SO 4 The electrocatalytic oxygen evolution reaction was tested as an electrolyte. The results showed that the material also has high electrocatalytic oxygen evolution activity and stability.
[0045] Example 3
[0046] (1) Weigh 1.0 g C 4 H 6 CoO 4 ·4H 2 O was added to 30 ml C 3 H 8 O 3After stirring and ultrasonication, a uniform slurry was obtained. The slurry was poured into a 50 mL polytetrafluoroethylene-lined autoclave, and the reactor was heated to 180°C for hydrothermal reaction. Then, the obtained viscous mixture was repeatedly washed with ethanol and dried at 60°C. Glycerol cobalt powder was obtained.
[0047] (2) Weigh 50 mg of glycerol cobalt and add it to 50 ml of ethanol. Ultrasonicate and stir until the solution becomes turbid. Then, dropwise add 15 mg of IrCl 3 ·3H 2 O solution, and then heated in an oil bath at 80 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h.
[0048] (3) Pour the prepared powder into a crucible and place it in a muffle furnace and calcine it at 350°C to obtain Ir-Co 3 O 4 V (Co) Powder. The obtained Ir-Co 3 O 4 V (Co) The content is 10wt%.
[0049] The catalyst prepared in this example was used as the anode. 2 SO 4 The electrocatalytic oxygen evolution reaction was tested as an electrolyte. The results showed that the material also has high electrocatalytic oxygen evolution activity and stability.
[0050] Comparative Example 1
[0051] Weigh 196 mg Co(NO 3 ) 2 6H 2 O and 189 mg HMT, dissolved in 12 ml HO. 2 O and 18 ml EG mixed solution. After stirring for 30 min, the solution was poured into a 50 ml stainless steel autoclave lined with polytetrafluoroethylene reactor and hydrothermally reacted at 120 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h to obtain Co(OH) 2 powder.
[0052] Weigh 50 mg Co(OH) 2 The powder was then added to 50 ml of ethanol, ultrasonicated and stirred for 30 min to form a turbid solution. Then, 10 mg IrCl 3 ·3H 2O solution, and then heated in an oil bath at 80 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h to obtain Ir-Co(OH) 2 powder.
[0053] Ir-Co(OH) 2 The powder was poured into a crucible and then placed in a muffle furnace and calcined at 350 °C to obtain Ir-Co 3 O 4 powder.
[0054] The catalyst prepared in this comparative example was used as the anode and 0.5 MH 2 SO 4 As an electrolyte for the electrocatalytic oxygen evolution reaction test, at 10 mA / cm 2 At a current density of , the overpotential is 306 mV.
[0055] Comparative Example 2
[0056] Weigh 1.0 g C 4 H 6 CoO 4 ·4H 2 O was added to 30 ml C 3 H 8 O 3 After stirring and ultrasonication, a uniform slurry was obtained. The slurry was poured into a 50 mL polytetrafluoroethylene-lined autoclave, and the reactor was heated to 180°C for hydrothermal reaction. Then, the obtained viscous mixture was repeatedly washed with ethanol and dried at 60°C. Glycerol cobalt powder was obtained.
[0057] The prepared powder was poured into a crucible and calcined in a muffle furnace at 350 °C to obtain Ir-Co 3 O 4 V (Co) powder.
[0058] The catalyst prepared in this comparative example was used as the anode and 0.5 MH 2 SO 4 As an electrolyte for the electrocatalytic oxygen evolution reaction test, at 10 mA / cm 2 At a current density of , the overpotential is 421 mV.
[0059] Comparative Example 3
[0060] Weigh 196 mg Co(NO 3 ) 2 6H 2 O and 189 mg HMT, dissolved in 12 ml HO.2 O and 18 ml EG mixed solution. After stirring for 30 min, the solution was poured into a 50 ml stainless steel autoclave lined with polytetrafluoroethylene reactor and hydrothermally reacted at 120 °C. The product was collected by centrifugation, washed three times with ultrapure water and ethanol, and finally dried in an oven at 60 °C for 10 h to obtain Co(OH) 2 powder.
[0061] Co(OH) 2 The powder was poured into a crucible and then placed in a muffle furnace and calcined at 350 °C to obtain Ir-Co 3 O 4 powder.
[0062] The catalyst prepared in this comparative example was used as the anode and 0.5 MH 2 SO 4 As an electrolyte for the electrocatalytic oxygen evolution reaction test, at 10 mA / cm 2 At a current density of , the overpotential is 429 mV.
[0063] The materials prepared in the above examples and comparative examples were subjected to relevant tests:
[0064] The porous nanosheet material prepared in this experimental example was used to conduct an electrocatalytic oxygen evolution test, and the main steps were as follows:
[0065] The Ir-Co prepared in Example 3 O 4 V (Co) The nanosheet material was dropped onto carbon paper with a loading of about 0.8 mg / cm2. 3 O 4 V (Co) The nanosheet material was used as the working electrode (WE), saturated calomel was used as the reference electrode (RE), and the carbon rod was used as the counter electrode (CE) to form a three-electrode system. 2 SO 4 Electrolyte. Calibrate the electrode before testing. .
[0066] Figure 3 The Ir-Co prepared by the present invention 3 O 4 V (Co) Nanosheet (Example 1) Catalyst and Ir-Co 3 O 4 (Comparative Example 1), Co 3 O 4 V (Co) (Comparative Example 2), Co 3 O 4(Comparative Example 3) and commercial IrO 2 Catalyst performance comparison chart. By LSV at 0.5 MH 2 SO 4 The electrocatalytic activity of the catalyst was evaluated in solution. 3 O 4 V (Co) The best catalytic activity was shown at a current density of 10 mA cm-2 with an overpotential of 245 mV, which is lower than that of Ir-Co 3 O 4 (306 mV), Co 3 O 4 (429 mV), commercial IrO 2 (360 mV) and Co 3 O 4 V (Co) (421 mV).
[0067] Figure 4 The Ir-Co prepared by the present invention 3 O 4 V (Co) Nanosheet (Example 1) Catalyst and Ir-Co 3 O 4 (Comparative Example 1), Co 3 O 4 V (Co) (Comparative Example 2), Co 3 O 4 (Comparative Example 3) and commercial IrO 2 Comparison of the stability of the catalysts. 3 O 4 V (Co) and Co 3 O 4 At 10 mA cm -2 The stable operation time at the current density is 10 h and 25 h respectively. 3 O 4 and Ir-Co 3 O 4 V (Co) At 10 mA cm -2 The stable operation time under the current density increased to 130 h and 600 h. The reason for the improved stability can be seen from the LSV curve. After the introduction of Ir with high activity, the Co 3 O 4 The reconstruction significantly improves the stability of the catalyst.
[0068] Figure 5 The Ir-Co prepared by the present invention 3 O4 V (Co) Nanosheet (Example 1) Catalyst and Ir-Co 3 O 4 (Comparative Example 1), Co 3 O 4 V (Co) (Comparative Example 2), Co 3 O 4 (Comparative Example 3) and commercial IrO 2 Tafel plot of catalyst comparison. Ir-Co 3 O 4 V (Co) The Tafel slope value is 74.6 mV dec -1 Significantly lower than Co 3 O 4 V (Co) (101.5 mV dec -1 ), commercial IrO 2 (112.1 mVdec -1 ), Ir-Co 3 O 4 (110.3 mV dec -1 ) and Co 3 O 4 (101.8 mV dec -1 ), indicating that Ir-Co 3 O 4 V (Co) Possessing the best electrocatalytic kinetics. 3 O 4 、Co 3 O 4 V (Co) , Commercial IrO 2 and Ir-Co 3 O 4 The difference in Tafel slope values is less than 10 mVdec -1 , indicating that they have similar reaction mechanisms and share the same rate steps.
[0069] Figure 6 The Ir-Co prepared by the present invention 3 O 4 V (Co) Nanosheet (Example 1) Catalyst and Ir-Co 3 O 4 (Comparative Example 1), Co 3 O 4 V (Co) (Comparative Example 2), Co 3 O 4 (Comparative Example 3) and commercial IrO2 CV diagram of the catalyst. Considering that the electrochemical ECSA is linearly related to Cdl, the Cdl of the catalyst was obtained by measuring the CV curve in the non-Faraday range. 3 O 4 After doping with Ir, Cdl increases significantly, Co 3 O 4 (0.64 mF cm -2 )、Co 3 O 4 V (Co) (0.92 mF cm -2 ) and Ir-Co 3 O 4 (2.05 mF cm -2 )、Ir-Co 3 O 4 V (Co) (2.49 mF cm -2 ), the Cdl values increased by 3.2 and 2.7 times after Ir doping, respectively. The significant increase in the electrochemical active area can be attributed to the introduction of high OER active sites.
[0070] Figure 7 The Ir-Co prepared by the present invention 3 O 4 V (Co) Nanosheet (Example 1) Catalyst and Ir-Co 3 O 4 (Comparative Example 1), Co 3 O 4 V (Co) (Comparative Example 2), Co 3 O 4 (Comparative Example 3) and commercial IrO 2 Comparative mass activity diagram of the catalysts. Ir-Co at 300 mV overpotential 3 O 4 V (Co) , Ir-Co 3 O 4 and commercial IrO 2 The mass activity of -1 Ir, 167 A g -1 Ir and 1.5 A g -1 Ir. From this we can conclude that Ir-Co 3 O 4 V (Co) Compared with Ir-Co 3 O 4 or commercial IrO 2It has higher intrinsic OER activity.
[0071] Figure 8 The Ir-Co prepared by the present invention 3 O 4 V (Co) Nanosheet (Example 1) in PEMWE at 80°C, 500 mA / cm 2 ~1000mA / cm 2 Stability test data under the following conditions; only 1.67V voltage is required to reach 1A / cm 2 The current density can reach 500mA / cm 2 ~1000mA / cm 2 It can operate stably for up to 3000 h at a current density of 1.547 W / m, fully demonstrating its excellent stability and efficient electrocatalytic activity.
[0072] The above embodiments describe in detail the structure, features and effects of the present invention. The above are only preferred embodiments of the present invention. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which do not exceed the scope covered by the specification, should be within the protection scope of the present invention.
Claims
1. Ir-Co3O4V (Co) Nanosheets, characterized in that Ir single atoms and clusters supported on Co3O4V (Co) The nanosheets have an average size of 100 nm; the Ir-Co3O4V (Co) In the nanosheets, the Ir content is 2 to 10 wt%.
2. An Ir-Co3O4V as claimed in claim 1 (Co) The method for preparing a nanosheet is characterized in that: The following steps are involved: (1) 1.0 g of C4H6CoO4·4H2O was added to 30 ml of C3H8O3, and a uniform slurry was obtained after stirring and ultrasonication. The slurry was subjected to a hydrothermal reaction at 180 °C. Then, the obtained viscous mixture was repeatedly washed with ethanol and dried to obtain glycerol cobalt powder; (2) Add 50 mg of glycerol cobalt to 50 ml of ethanol, sonicate and stir; then, dropwise add 5-15 mg of IrCl3·3H2O solution, and then heat in an 80°C oil bath; collect the product by centrifugation, wash the product three times with ultrapure water and ethanol, and dry to obtain Ir-doped glycerol cobalt; (3) The prepared powder was calcined at 350 °C to obtain Ir-Co3O4V (Co) powder.
3. The preparation method according to claim 2, characterized in that: The drying temperature in step 1 is 60°C.
4. The preparation method according to claim 2, characterized in that: The drying method in step 3 is drying in an oven at 60°C for 10 h.
5. The preparation method according to claim 2, characterized in that: The calcination time in step 4 is 12 hours.
6. Ir-Co3O4V as claimed in claim 1 (Co) Application of nanosheets as anode for hydrogen production in proton exchange membrane water electrolysis (PEMWE).