A high-entropy alloy coating with hydrogen evolution and oxygen evolution dual catalytic performance, a preparation method and application thereof

Abstract

The application belongs to the field of electrocatalysts, and specifically discloses a high-entropy alloy coating with hydrogen evolution and oxygen evolution dual-catalytic performance, a preparation method and application thereof, a FeCoCrNiAlCu HEA coating is prepared, and is used for water electrolysis technology under acidic conditions; the experimental results show that the FeCoCrNiAlCu HEA coating has excellent dual-function catalytic capacity, and shows good hydrogen evolution (HER) and oxygen evolution (OER) catalytic performance in a 0.5M H2SO4 electrolyte. The existence of the holes in the coating is a key factor for exposing active sites, and the metal oxides further promote the reaction; and the synergistic effect of the multiple elements in the HEA makes the coating have good catalytic performance, shows small overpotential and Tafel slope, and has good reaction stability; the application not only provides a new strategy for preparation of non-noble metal HEA catalysts, but also provides an effective method for practical application of high-efficiency HEA electrocatalysts.

Description

Technical Field

[0001] This invention relates to the field of electrocatalysts, and in particular to a high-entropy alloy coating with dual catalytic properties of hydrogen evolution and oxygen evolution, its preparation method, and its application. Background Technology

[0002] In the global transition from traditional to clean energy, hydrogen energy is considered an important clean energy source due to its high energy density, sustainability, and pollution-free combustion. Electrochemical water splitting for hydrogen production via the cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) is a promising pathway for converting solar, water, and wind energy into chemical energy, as the absence of pollutants during the reaction facilitates achieving carbon peaking. However, the sluggish kinetics of the cathodic hydrogen evolution reaction (HER) lead to excessively high overpotentials in practical applications. While noble metals such as Pt, Ir, Ru, and their compounds exhibit lower overpotentials and better reaction kinetics in practical applications, their high cost and resource scarcity limit their widespread industrial application. Therefore, developing electrocatalysts with high economic efficiency and excellent catalytic activity is crucial. Based on the "volcano diagram" showing an initial increase followed by a decrease in MH bond strength as a function of HER catalyst activity, optimized catalysts based on low-cost transition metals should possess MH bond strength comparable to platinum. In past research, inexpensive and abundant 3d transition metals (TMs) such as Fe, Co, Ni, and their compounds have been widely used in the field of electrocatalysis.

[0003] However, 3d transition metals exhibit poor stability and catalytic performance under acidic reaction conditions. Developing efficient and stable transition metal alloys is crucial for promoting the development and practical application of electrochemical pyrolysis technology. High-entropy alloys (HEAs) composed of five or more different atoms (5%-35%) have attracted considerable attention due to their unique high-entropy effect, lattice distortion effect, cocktail effect, and retarded diffusion effect. Based on the four unique effects of high-entropy alloys and the wide adsorption energy intensity generated by the random arrangement of atoms on their surface, they have become potential materials for various catalytic reactions. Among these, the severe lattice distortion effect and retarded diffusion effect caused by different atomic sizes greatly enhance the corrosion resistance of high-entropy alloys under acidic and alkaline conditions. Aimi et al. prepared a nine-element self-reconstructed high-entropy alloy by melting and then crushing, which exhibited excellent oxygen evolution reaction (OER) stability under acidic conditions. Frank et al. prepared a CoCrFeNi equimolar ratio high-entropy alloy by arc melting, which showed good stability and hydrogen evolution reaction (HER) performance under acidic conditions. Liu et al. prepared nanoporous NiMnFeMo materials by dealloying, which exhibited excellent water splitting activity under alkaline conditions. Among various preparation methods, HEAs prepared by plasma spraying have been extensively studied due to their low material consumption, excellent bonding strength, good wear resistance, and corrosion resistance. However, their use as electrocatalysts remains in the exploratory stage. During plasma spraying, the process characteristics create pores in the coating, which helps increase the specific surface area of ​​the reaction and expose more reactive sites. Furthermore, the metal oxides generated during spraying alter the electron configuration of the metal, potentially further promoting the reaction. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a high-entropy alloy coating with dual catalytic properties for hydrogen evolution and oxygen evolution, its preparation method, and its application.

[0005] To achieve the above objectives, the present invention is implemented according to the following technical solution:

[0006] One objective of this invention is to provide a method for preparing a high-entropy alloy coating with dual catalytic properties of hydrogen evolution and oxygen evolution, comprising the following steps:

[0007] S1. Take Fe, Co, Cr, Ni, Al and Cu elemental metals with a purity higher than 99.9% according to the molar ratio 1:1:1:1:1:1, clean and remove oil and impurities from the surface of each metal raw material, rinse with alcohol and blow dry for later use.

[0008] S2. Place the various metal raw materials into an electric arc furnace and melt them into FeCoCrNiAlCu high-entropy alloy;

[0009] S3. The FeCoCrNiAlCu high-entropy alloy is processed into FeCoCrNiAlCu high-entropy alloy powder for spraying using a vacuum gas atomization device.

[0010] S4. Clean the substrate surface before spraying and sandblast the substrate surface to increase the surface roughness.

[0011] S5. Use plasma spraying equipment to spray FeCoCrNiAlCu high entropy alloy powder onto the substrate surface to prepare a HEA coating. The main parameters of the spraying are: working voltage: 42V, working current: 600A, argon flow rate: 45L / min.

[0012] Furthermore, the main parameters of the vacuum gas atomization device are: gas atomization pressure of 5.0 MPa, heating power of 30 kW, feeding speed of 0.05 mm / s, and sieving of alloy powder with a particle size of 14-45 μm for spraying.

[0013] Preferably, the substrate is a Q235 steel plate.

[0014] Preferably, the sandblasting material used in the sandblasting process is white fused alumina (Al2O3).

[0015] Preferably, the thickness of the HEA coating is 400 μm.

[0016] The second objective of this invention is to provide a high-entropy alloy coating with dual catalytic performance of hydrogen evolution and oxygen evolution prepared by the above method.

[0017] The third objective of this invention is to provide a high-entropy alloy coating with dual catalytic performance for hydrogen and oxygen evolution as a dual catalyst for water electrolysis.

[0018] Compared with existing technologies, this invention successfully prepared a FeCoCrNiAlCu HEA coating and applied it to water electrolysis under acidic conditions. Experimental results show that the FeCoCrNiAlCu HEA coating possesses excellent bifunctional catalytic activity, exhibiting good hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalytic performance in 0.5 M H₂SO₄ electrolyte. The presence of pores in the coating is a key factor in exposing active sites, and the metal oxide further promotes the reaction. Furthermore, the synergistic effect of multiple elements in the HEA gives the coating good catalytic performance, exhibiting a small overpotential, Tafel slope, and good reaction stability. This invention not only provides a new strategy for the preparation of non-noble metal HEA catalysts but also offers an effective method for the practical application of highly efficient HEA electrocatalysts. Attached Figure Description

[0019] Figure 1Structural characterization of the FeCoCrNiAlCu HEA coating prepared for embodiments of the present invention: (a) FeCoCrNiAlCu high-entropy alloy powder; (b) XRD pattern; (c) Scanning electron microscope image of the FeCoCrNiAlCu HEA coating; (d) Scanning electron microscope image and energy dispersive spectroscopy (EDS) spectrum of the FeCoCrNiAlCu HEA coating.

[0020] Figure 2 XPS spectra of FeCoCrNiAlCu HEA coating and bulk FeCoCrNiAlCu high-entropy alloy prepared for embodiments of the present invention: (a) iron 2p orbital; (b) cobalt 2p orbital; (c) chromium 2p orbital; (d) nickel 2p orbital; (e) aluminum 2p orbital; (f) copper 2p orbital.

[0021] Figure 3 OER test performance of the FeCoCrNiAlCu HEA coating prepared for the present invention: (a) LSV curve of oxygen evolution reaction; (b) Tafel plot; (c) double layer capacitance of oxygen evolution reaction.

[0022] Figure 4 The HER test performance of the FeCoCrNiAlCu HEA coating prepared for the embodiments of the present invention is as follows: (a) LSV curve of hydrogen evolution reaction; (b) Tafel plot; (c) double layer capacitance of hydrogen evolution reaction; (d) Nyquist plot; (e) stability test of hydrogen evolution reaction; (f) LSV curve of overall water decomposition.

[0023] Figure 5 The following are scanning electron microscope (SEM) images, energy dispersive spectroscopy (EDS) spectra, and XPS spectra of the FeCoCrNiAlCu HEA coatings prepared according to embodiments of the present invention after cycling: (a) SEM image of the FeCoCrNiAlCu HEA coating after cycling; (b) XPS spectrum of iron 2p orbitals after cycling; (c) XPS spectrum of cobalt 2p orbitals after cycling; (d) XPS spectrum of chromium 2p orbitals after cycling; (e) XPS spectrum of nickel 2p orbitals after cycling; (f) XPS spectrum of aluminum 2p orbitals after cycling; (g) XPS spectrum of copper 2p orbitals after cycling. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0025] S1. Take Fe, Co, Cr, Ni, Al and Cu elemental metals with a purity higher than 99.9% according to the molar ratio 1:1:1:1:1:1, clean and remove oil and impurities from the surface of each metal raw material, rinse with alcohol and blow dry for later use.

[0026] S2. Place the various metal raw materials into an electric arc furnace and melt them into FeCoCrNiAlCu high-entropy alloy;

[0027] S3. A vacuum gas atomization device is used to process FeCoCrNiAlCu high-entropy alloy into FeCoCrNiAlCu high-entropy alloy powder for spraying. The main parameters of the vacuum gas atomization device are: gas atomization pressure of 5.0MPa, heating power of 30kW, feeding speed of 0.05mm / s, and alloy powder with a particle size of 14-45μm is screened for spraying.

[0028] S4. Using Q235 steel plate as the substrate, clean the surface of the substrate before spraying, and sandblast the surface of the substrate to increase the surface roughness of the substrate. The sandblasting material is white corundum Al2O3.

[0029] S5. FeCoCrNiAlCu high-entropy alloy powder was sprayed onto the substrate surface using a Praxair 3710 plasma spraying equipment to obtain a FeCoCrNiAlCu HEA coating. The main spraying parameters were: working voltage: 42V, working current: 600A, argon flow rate: 45L / min, and the spraying thickness of the FeCoCrNiAlCu HEA coating was 400μm.

[0030] The FeCoCrNiAlCu HEA coating was cut into 10mm×5mm×2mm pieces using a DK7720 cutting machine, and the workpiece and wires were encapsulated with epoxy resin for subsequent electrochemical testing.

[0031] Comparative Example 1

[0032] The difference from Example 1 is that FeCoCrNiCu high-entropy alloy is used.

[0033] Comparative Example 2

[0034] The difference from Example 1 is that FeCoCrNiAl high-entropy alloy is used.

[0035] Material characterization was performed on the high-entropy alloys and HEA coatings of Example 1, Comparative Example 1, and Comparative Example 2, respectively.

[0036] The morphology and structure of the samples were characterized using scanning electron microscopy (Gemini 300), X-ray diffraction (Shimadzu-7000) with scanning angles of 20°–80°, X-ray photoelectron spectroscopy (XPS, Thermo Science K-Alpha), and transmission electron microscopy (JEM2100). The coated surfaces were prepared for observation by polishing with sandpaper of different grits and then with 20000# diamond polishing paste.

[0037] The structural characterization results of the prepared FeCoCrNiAlCu HEA coating are as follows: Figure 1 As shown: (a) FeCoCrNiAlCu high-entropy alloy powder; (b) XRD pattern; (c) Scanning electron microscope image of FeCoCrNiAlCu HEA coating; (d) Scanning electron microscope image and energy dispersive spectroscopy (EDS) spectrum of FeCoCrNiAlCu HEA coating. Figure 1 As shown in (a) of the image, Cu in the as-cast FeCoCrNiAlCu HEA exhibits segregation due to its high electronegativity, while the other elements are uniformly distributed. The morphology and elemental distribution of the FeCoCrNiAlCu HEA powder after atomization are shown below. Figure 1 As shown in (a), the powder surface has good formability, exhibiting regular circular shapes without obvious defects, and the elemental distribution is uniform without segregation under macroscopic EDS. The morphology and elemental distribution of the remaining high-entropy alloy powder are as follows. Figure 1 As shown in (b) and (c), a high-entropy alloy coating was prepared on a Q235 substrate using plasma spraying technology. Figure 1 The X-ray diffraction patterns of FeCoCrNiAlCu HEA and FeCoCrNiAlCu HEA coatings shown in (b) are quite similar to those of the as-cast state, indicating that the diffraction peak distribution did not change significantly after spraying. The stronger (111) and (200) diffraction peaks located at 2θ = 43.494° and 50.673° indicate that the coating and HEA alloy body have a face-centered cubic structure. The (021) diffraction peak of the coating located at 2θ = 37.239° is a metal oxide diffraction peak (PDF#89-3080). The remaining components' X-ray diffraction patterns are shown below. Figure 1 As shown in (b) above. The interface between the coating and the substrate is as follows. Figure 1 As shown in (c) of the figure, the bonding between the coating and the substrate is a micro-regional metallurgical bond with good bonding strength, making it difficult to peel off during the catalytic reaction process. The morphology of the bonding area between the FeCoCrNiAl, FeCoCrNiCu HEA coatings and the FeCoCrNiAlCuHEA coating is similar. Figure 1As shown in (d), the coating morphology exhibits a standard river-like pattern, a typical morphology of thermal spraying. This is because the powder melts rapidly during the spraying process, with some unmelted particles and droplets rapidly impacting the substrate surface layer by layer to form a layered stacked structure. The elemental distribution of Cu and Al differs from that of other elements in the coating, possibly due to differences in electronegativity and reactivity in air during the spraying process. The segregation of Cu can increase the conductivity of the coating during the reaction process. Furthermore, the presence of metal oxides can be observed in the prepared coating elements. Due to the excessively high plasma jet temperature, oxidation of the metals is inevitable even with argon protection in an atmospheric environment. Al, due to its high reactivity, shows a high degree of overlap with oxygen in its elemental distribution.

[0038] To investigate the valence states of the metal elements in the coating, X-ray photoelectron spectroscopy (XPS) was used to compare the as-cast FeCoCrNiAlCu HEA and the FeCoCrNiAlCu HEA coating. The XPS spectra of the prepared FeCoCrNiAlCu HEA coating and the bulk FeCoCrNiAlCu high-entropy alloy are shown below. Figure 2 As shown: (a) iron 2p orbital; (b) cobalt 2p orbital; (c) chromium 2p orbital; (d) nickel 2p orbital; (e) aluminum 2p orbital; (f) copper 2p orbital. (From...) Figure 2 From (a) we can see that Fe in the coating 2+ Fe 3+ The peak intensity is significantly higher than that of the as-cast HEA, with Fe 2+ Fe 3+ 2p 3 / 2 The peak binding energies shifted from 709.53 eV and 711.61 eV to 709.73 eV and 711.97 eV, respectively, and Fe 2+ Fe 3+ The proportion increased from 0.69 in the as-cast state to 0.86, indicating that some Fe was oxidized during the spraying process, and the formation of high-valence Fe facilitated the adsorption of HER reaction intermediates. Figure 2 From (b) we can see that Co 2+ Co 3+ 2p 3 / 2 The binding energy shifted from 782.78 eV and 780.71 eV to 780.10 eV and 784.04 eV, where Co 2+ The proportion increased from 0.15% in the as-cast state to 0.21%, and Co increased during the reaction process. 2+ The presence of this substance can release a large number of free electrons and transform into Co. 3+ Promotes the reaction. (By) Figure 2As shown in (d), the binding energy shifts from 872.24 eV and 875.70 eV to 873.63 eV and 877.59 eV, proving that oxidation occurred during the spraying process, resulting in a higher valence state. However, due to Ni's excellent high-temperature performance, Ni... 2+ Ni 3+ The proportions did not change significantly. Figure 2 From (c), we can know that Cr 3+ The proportion increased slightly from 0.88% to 0.9% because Cr is highly reactive and forms a large amount of oxide in the as-cast state. 0 With Cr 3+ The shift towards a lower binding energy indicates that it is in an electron-rich state. Figure 2 As can be seen from (f) in the figure, due to the segregation of Cu element in the coating, Cu... 2+ The electrons shift towards electron-rich, low-binding-energy directions; the presence of Cu provides good electrical conductivity and a large number of free electrons for the reaction. Figure 2 From (e), we can know that Al 0 The complete disappearance is due to the high affinity of Al for O, which is consistent with the EDS analysis results. The presence of transition metal oxides in the coating provides a significant amount of vacant oxygen; Figure 2 As shown in (d), the O1s spectrum has three characteristic peaks, corresponding to metal oxide (MO), defect / vacancy oxygen, and hydroxyl or surface adsorbed oxygen, respectively. Compared with the cast HEA, the proportion of metal oxide (MO) peak in the FeCoCrNiAlCu HEA coating is significantly enhanced, increasing from 0.06 to 0.25. The increase in metal oxide can increase the presence of vacancy oxygen, and more vacancy oxygen helps to reduce the overpotential of the OER reaction.

[0039] Electrochemical Measurement

[0040] The high-entropy alloys and HEA coatings of Examples 1, 1, and 2 were respectively immersed in 0.5 M H₂SO₄ (pH = 0.3) electrolyte. A standard three-electrode system was used, with the HEA coating as the working electrode, a saturated calomel electrode as the reference electrode, and a carbon rod as the counter electrode. HER and OER tests were performed on a CHI660E electrochemical workstation. The immersion area of ​​the HEA coating in the electrolyte was 0.5 cm². -2 HER was performed using a linear voltammetric scan at a scan rate of 5 mV / s. -1 Select 2mV s -1OER data were obtained by scanning at high speed. All IR compensation values ​​were 95%. The Tafel slope was calculated using the relationship between potential and current density (logarithm) on the LSV curve, with the formula η = b × logj + a. Electrochemical impedance spectroscopy measurements were performed at frequencies ranging from 0.01 Hz to 100 kHz. The electrochemically active surface area (ECSA) of the coating was determined using double-layer capacitance (Cdl). All measured potentials were converted to reversible hydrogen potentials, with the formula E(RHE) = E(SCE) + 0.059 × pH + 0.2412 V.

[0041] The OER test performance of the prepared FeCoCrNiAlCu HEA coating is as follows: Figure 3 As shown: (a) LSV curve of the oxygen evolution reaction; (b) Tafel plot; (c) double-layer capacitance of the oxygen evolution reaction. Figure 3 From (a) in the figure, we can see that the oxygen evolution reaction occurs at a current density of 10 mA cm⁻¹. -2 The overpotentials of the FeCoCrNiAlCu HEA-coated catalysts are 270 mV, FeCoCrNiAl (300 mV), and FeCoCrNiCu (303 mV). Figure 3 From (b) we can see that the Tafel slope of the FeCoCrNiAlCu HEA coating is (76.68mV / dec). -1 ), less than FeCoCrNiAl (201.97mV / dec -1 ), FeCoCrNiCu (157.17mV / dec) -1 This indicates that the FeCoCrNiAlCu HEA coating exhibits a relatively fast response rate in the OER reaction. Figure 3 From (c), it can be seen that the FeCoCrNiAlCuHEA coating has the highest C. dl Value (7.58mF cm) -2 This indicates that it has the largest active specific surface area compared to other components.

[0042] The HER performance of the prepared FeCoCrNiAlCu HEA coating is as follows: Figure 4 As shown: (a) LSV curve of the hydrogen evolution reaction; (b) Tafel plot; (c) double-layer capacitance of the hydrogen evolution reaction; (d) Nyquist plot; (e) stability test of the hydrogen evolution reaction; (f) LSV curve of overall water splitting. Figure 4 From (a) we can see that at a current density of 10 mA cm⁻¹ -2 The overpotential of the FeCoCrNiAlCu HEA-coated catalyst (99.3 mV) is lower than that of FeCoCrNiAlCu in its as-cast state (134 mV), FeCoCrNiAl (118 mV), and FeCoCrNiCu (121 mV). This is due to... Figure 4 (b) shows that, compared with other samples, FeCoCrNiAlCu in the as-cast state (98.4 mV / dec) -1 ), FeCoCrNiAl (74.72mV / dec) -1 ), FeCoCrNiCu (69.71mV / dec -1 Compared to the FeCoCrNiAlCu HEA coating, the FeCoCrNiAlCu HEA coating has the lowest Tafel slope (55.8 mV / dec). -1 The reaction is similar to that of commercial Pt / C electrodes. According to the Tafel slope diagram, the reaction mechanism of the HEA coating under acidic conditions is Volmer-Heyrosky, with the rate-determining step being Volmer. The morphology of the coating after the reaction is as follows... Figure 5 As shown in (a), rice-grain-like precipitates appear near the surface pores, and the coating surface undergoes etching during the reaction, further increasing the contact area between the solution and the workpiece. The results indicate that the pores and synergistic effect of multiple elements in the coating promote the reaction and improve the catalytic kinetics of the catalyst. Figure 4 As shown in (c), the FeCoCrNiAlCu HEA coating (2.4mF cm) -2 The value is much smaller than other prepared samples, but its lowest overpotential indicates a higher intrinsic active site. Figure 4 As shown in (d), compared to the other components, the FeCoCrNiAlCu HEA coating has the lowest equivalent resistance (1.597 Ω), indicating low electron transfer resistance and faster electron transport rate during the reaction. Stability is an important reference factor in acidic reactions. To determine the stability of the FeCoCrNiAlCu HEA coating sample in the HER reaction under acidic conditions, 3000 cycles of CV were performed within the working range. Figure 4 As shown in (e), the reaction overpotential decreases slightly after 1000 cycles, possibly because further etching of the coating surface and pores increases reaction sites and promotes the reaction. The overpotential fluctuations are smaller after 2000 and 3000 cycles, indicating that the FeCoCrNiAlCu HEA coating exhibits good reaction stability in acidic electrolyte. Figure 4 From (f) in the figure, we can see that at 10mA cm -2 Compared with FeCoCrNiCu (1.58V), the FeCoCrNiAlCu HEA coating (1.47V) has a lower potential requirement and exhibits better overall water electrolysis performance.

[0043] Following HER stability testing, the structural characteristics of the FeCoCrNiAlCu HEA-coated catalyst were analyzed. The scanning electron microscope (SEM) image and energy dispersive X-ray spectroscopy (EDS) spectrum of the prepared FeCoCrNiAlCu HEA coating after cycling are shown below. Figure 5 As shown: (a) SEM image of FeCoCrNiAlCu HEA coating after cycling; (b) XPS spectrum of iron 2p orbitals after cycling; (c) XPS spectrum of cobalt 2p orbitals after cycling; (d) XPS spectrum of chromium 2p orbitals after cycling; (e) XPS spectrum of nickel 2p orbitals after cycling; (f) XPS spectrum of aluminum 2p orbitals after cycling; (g) XPS spectrum of copper 2p orbitals after cycling. Figure 5 As shown in (b) of the figure, Fe in the Fe 2p energy spectrum 2+ Fe 3+ The increased proportion and the rise in binding energy from 709.73 eV and 711.79 eV to 711.09 eV and 714.32 eV respectively indicate that the Fe was further oxidized to a higher oxidation state during the reaction, with a very small amount of Fe remaining. 0 Its presence may be due to being covered by reactants and not participating further in the reaction. Figure 5 From (c) and (e), we can see that Co and Ni have similar trends to Fe. In the Co energy spectrum, Co... 0 Completely disappeared Co 2+ With Co 3+ The increased proportion indicates that Co and Co2 reacted during the reaction. 2+ The large number of free electrons contributed by the reaction facilitated its progress. Figure 5 As shown in (d) of the Cr spectrum, after stability testing, Cr... 0 The complete disappearance of Cr indicates that Cr contributed some electrons in the reaction, but Cr... 3+ The peak showed no significant change overall. Figure 5 As shown in (f), the Al spectrum is similar to that of Cr. 0 It completely disappears during the reaction, and Al 3+ The binding energy shifts slightly to the right from 74.56 eV to 74.65 eV. These results indicate that Al and Cr are good stabilizing elements in the FeCoCrNiAlCu HEA coating catalytic reaction. Figure 5 As can be seen from (g) in the Cu energy spectrum, the Cu deposits on the surface are covered by Cu precipitates. 2+The peak intensity increased significantly, and the binding energy increased from 932.68 eV to 933.12 eV, indicating that Cu contributed a large number of electrons to be oxidized to a higher valence state during the reaction.

[0044] In summary, the FeCoCrNiAlCu HEA coating prepared by this invention possesses excellent bifunctional catalytic ability, exhibiting good hydrogen evolution (HER) and oxygen evolution (OER) catalytic performance in 0.5M H2SO4 electrolyte.

[0045] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. The application of a high-entropy alloy coating with dual catalytic performance for hydrogen evolution and oxygen evolution in the dual catalyst for hydrogen evolution and oxygen evolution in acidic water electrolysis, characterized in that, A method for preparing a high-entropy alloy coating with dual catalytic properties for hydrogen evolution and oxygen evolution includes the following steps: S1. Take Fe, Co, Cr, Ni, Al and Cu elemental metals with a purity higher than 99.9% according to the molar ratio 1:1:1:1:1:1, clean and remove oil and impurities from the surface of each metal raw material, rinse with alcohol and blow dry for later use. S2. Place the various metal raw materials into an electric arc furnace and melt them into FeCoCrNiAlCu high-entropy alloy; S3. The FeCoCrNiAlCu high-entropy alloy is processed into FeCoCrNiAlCu high-entropy alloy powder for spraying using a vacuum gas atomization device. S4. Clean the substrate surface before spraying and sandblast the substrate surface to increase the surface roughness. S5. Using plasma spraying equipment, FeCoCrNiAlCu high-entropy alloy powder is sprayed onto the substrate surface to prepare a HEA coating with a thickness of 400 μm, i.e., a high-entropy alloy coating. The spraying parameters are: working voltage: 42 V, working current: 600 A, argon flow rate: 45 L / min.

2. The application of the high-entropy alloy coating with dual catalytic performance for hydrogen and oxygen evolution as described in claim 1 as a dual catalyst for hydrogen and oxygen evolution in acidic water electrolysis, characterized in that: The parameters of the vacuum gas atomization device are as follows: gas atomization pressure is 5.0 MPa, heating power is 30 kW, feeding speed is 0.05 mm / s, and alloy powder with a particle size of 14-45 μm is screened for spraying.

3. The application of the high-entropy alloy coating with dual catalytic performance for hydrogen and oxygen evolution as described in claim 1 as a dual catalyst for hydrogen and oxygen evolution in acidic water electrolysis, characterized in that: The substrate is Q235 steel plate.

4. The application of the high-entropy alloy coating with dual catalytic performance for hydrogen and oxygen evolution as described in claim 1 as a dual catalyst for hydrogen and oxygen evolution in acidic water electrolysis, characterized in that: The sandblasting material used in the sandblasting process is white corundum Al2O3.

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