Turing catalyst, preparation method and application thereof, and membrane electrode reactor

Abstract

The invention provides a Turing catalyst, a preparation method and application thereof, and a membrane electrode reactor. The preparation method of the Touling catalyst comprises the following steps: co-sputtering an M target material and an N target material, and depositing on the surface of a substrate to form an M-N film; wherein M is one or more of Ru, Os, Rh, Ir, Pd, Pt, Ag and Au; wherein N is one or more of Zn, Si, Al and Pb; and placing the M-N film in an alkaline solution for etching to obtain the Turing catalyst. The Turing catalyst prepared according to the invention has high quality activity, good stability and single composition, and can solve the problem that the recoverability and sustainability of scarce noble metals are hindered in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts for producing hydrogen by decomposing water, and in particular to a Turing catalyst, a preparation method and application thereof, and a membrane electrode reactor. Background Art

[0002] Precious metals are an important class of catalysts for hydrogen production by water decomposition. In the prior art, one of the methods to improve the quality and activity of precious metal catalysts is to design catalysts with multiple components, but this hinders the recyclability and sustainability of scarce precious metals.

[0003] In view of this, it is necessary to provide a precious metal catalyst with a single component, high quality activity and good stability. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a Turing catalyst and its preparation method and application and membrane electrode reactor, wherein the catalyst has high mass activity and good stability.

[0005] To achieve the above object, the present invention provides a method for preparing a Turing catalyst, wherein the preparation method comprises:

[0006] By sputtering the M target and the N target together, a MN film is deposited on the surface of the substrate;

[0007] Wherein, M is one or a combination of two or more of Ru, Os, Rh, Ir, Pd, Pt, Ag, and Au;

[0008] Wherein, the N is one or a combination of two or more of Zn, Si, Al, and Pb;

[0009] The MN film is placed in an alkaline solution for etching to obtain the Turing catalyst.

[0010] According to a specific embodiment of the present invention, preferably, the preparation method comprises the following specific steps:

[0011] Depositing a buffer layer on the substrate, and then depositing the MN film on the surface of the buffer layer;

[0012] Preferably, the material of the buffer layer is one of Si, Zn, Sn, Al and Pb.

[0013] According to a specific embodiment of the present invention, preferably, the thickness of the MN film is 1-20 nm, more preferably 6 nm.

[0014] According to a specific embodiment of the present invention, preferably, the solute in the alkaline solution includes NaOH and / or KOH.

[0015] According to a specific embodiment of the present invention, preferably, the concentration of the alkaline solution is 0.1-6M, more preferably 0.1M.

[0016] According to a specific embodiment of the present invention, preferably, after the etching is completed, the etched sample is heat treated at 40 to 95° C. for 10 to 90 minutes, followed by washing and centrifugation to obtain the Turing catalyst.

[0017] According to a specific embodiment of the present invention, preferably, in the MN film, the percentage of M is 15 to 80 at.%, and the percentage of N is 20 to 85 at.%, calculated in atomic percentage.

[0018] According to a specific embodiment of the present invention, preferably, the deposition is physical vapor deposition;

[0019] Preferably, the deposition rate of the physical vapor deposition is 1 to 10 nanometers per minute;

[0020] Preferably, the base pressure before deposition is 1.0×10 -6 ~9.0×10 -6 torr, and the argon pressure during deposition was 1×10 -3 ~12×10 -3 torr.

[0021] The present invention also provides a Turing catalyst, which is prepared by the above preparation method. The Turing catalyst has a Turing structure, specifically an ultrafine Turing-type nanonet, and the Turing nanonet has a high-density twin boundary, and the Turing structure produces abundant low-coordinated atoms, providing much more electrochemically active surface area than nanosheets and nanoparticles; therefore, the mass activity of the Turing catalyst of the present invention is greatly improved, showing excellent electrolytic water catalytic performance. The Turing catalyst of the present invention has excellent hydrogen evolution mass activity, and when the Ir Turing catalyst is used, it also has good oxygen evolution mass activity.

[0022] The present invention also provides application of the Turing catalyst in water electrolysis.

[0023] The present invention also provides a membrane electrode reactor, wherein the cathode and anode of the membrane electrode reactor are respectively prepared from the above-mentioned Turing catalyst.

[0024] According to a specific embodiment of the present invention, preferably, the cathode and the anode are prepared by the following method:

[0025] The Turing catalyst is placed in a mixture of ethanol and an ionomer solution (for example, sustainion XA-9 ionomer ethanol dispersion) (the volume fraction of the ionomer solution is 1-10%) for ultrasonic treatment to obtain a catalyst ink;

[0026] Spraying the catalyst ink onto carbon paper to obtain the cathode;

[0027] The anode is obtained by spraying catalyst ink onto platinum-coated titanium felt.

[0028] The Turing catalyst provided by the present invention is a highly active, stable and simple nanocatalyst, which demonstrates the possibility of high-performance catalyst catalysis. Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0029] (1) The Turing catalyst provided by the present invention has a Turing structure and a high-density twin boundary, and the Turing structure produces abundant low-coordinated atoms, providing a much larger electrochemically active surface area than nanosheets and nanoparticles; therefore, the mass activity of the Turing catalyst of the present invention is greatly improved, showing excellent hydrogen evolution reaction performance.

[0030] (2) When Ir is used to construct the Turing catalyst of the present invention, it has the dual functions of hydrogen evolution and oxygen evolution, has the potential for complete water decomposition, and has broad application prospects.

[0031] (3) The Turing catalyst provided by the present invention has a single constituent element, which is conducive to the recovery and reuse of scarce precious metals.

[0032] (4) The Turing catalyst provided by the present invention has excellent long-term stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of the Turing catalyst according to the present invention is shown.

[0034] Figure 2 In the figure, a shows the TEM image of the Pt Turing catalyst of Example 1; b shows the TEM image of the Ir Turing catalyst of Example 1; and c shows the TEM image of the Pt nanosheets in Comparative Example 1.

[0035] Figure 3 In the figure, a shows the HRTEM image of the Pt Turing catalyst of Example 1; b shows the Fourier transform diffraction pattern of the Pt Turing catalyst of Example 1; c shows the twin boundary density of the Pt Turing catalyst of Example 1.

[0036] Figure 4In the figure, a shows the HRTEM image of the Ir Turing catalyst of Example 1; b shows the HRTEM image of the Ir Turing catalyst of Example 1.

[0037] Figure 5 The twin boundary densities of the Pt Turing catalyst of Example 1, the Ir Turing catalyst, the Pt nanosheets of Comparative Example 1, and the Ir nanosheets are shown.

[0038] Figure 6 XANES spectra of the Pt Turing catalyst of Example 1 and the Pt nanosheets of Comparative Example 1 are shown.

[0039] Figure 7 In the figure, a shows the Pt Turing catalyst of Example 1, the Pt nanosheet of Comparative Example 1, the Pt foil of Comparative Example 2, and the standard sample PtO 2 EXAFS spectra of the Ir Turing catalyst of Example 1, the Ir nanosheets of Comparative Example 1, the Ir foil of Comparative Example 2, and the IrO x EXAFS spectra of the catalyst; c shows the atomic coordination number data of the Pt Turing catalyst and the Ir Turing catalyst in Example 1 and Example 2.

[0040] Figure 8 In the figure, a shows the ICP-OES spectra of the Pt Turing catalyst and the Ir Turing catalyst of Example 1 and the Pt nanosheets and the Ir nanosheets of Comparative Example 1; and b shows the XPS spectra of the Pt Turing catalyst and the Ir Turing catalyst of Example 1.

[0041] Fig. 9 Polarization curves of the Pt Turing catalyst of Example 1, the Pt nanosheets of Comparative Example 1, and the Pt / C catalyst of Comparative Example 3 are shown.

[0042] Fig.10 The Tafel slope (left axis) and mass activity (right axis) of the Pt Turing catalyst of Example 1, the Pt nanosheets of Comparative Example 1, and the Pt / C catalyst of Comparative Example 3 are shown.

[0043] Fig.11 Polarization curves obtained before and after cyclic voltammetry of the Pt Turing catalyst of Example 1 and the Pt / C catalyst of Comparative Example 3 are shown.

[0044] Fig.12 Polarization curves of the Pt Turing catalyst of Example 1 and the Pt / C catalyst of Comparative Example 3 at 298K and atmospheric pressure in an anion exchange membrane water electrolyzer using a PtIr mesh as an anode catalyst are shown.

[0045] Fig.13The chronoamperometric test curve of the Pt Turing catalyst of Example 1 at 298K and atmospheric pressure in an anion exchange membrane water electrolyzer using a PtIr mesh as an anode catalyst is shown.

[0046] Fig.14 The hydrogen evolution performance polarization curves of the Ir Turing catalyst of Example 1, the Ir nanosheets of Comparative Example 1, and the Ir / C catalyst of Comparative Example 3 are shown.

[0047] Fig.15 The Ir Turing catalyst of Example 1, the Ir nanosheets of Comparative Example 1, the Ir / C catalyst of Comparative Example 3, and the IrO x Hydrogen evolution mass activity (left axis) and oxygen evolution mass activity (right axis) of the catalysts.

[0048] Fig.16 The Ir Turing catalyst of Example 1, the Ir / C catalyst of Comparative Example 3, and the IrO x Oxygen evolution polarization curves of the catalyst.

[0049] Fig.17 The electrochemical double layer capacitance of the Ir Turing catalyst of Example 1, the Ir nanosheet of Comparative Example 1, and the Ir / C catalyst of Comparative Example 3 are shown.

[0050] Fig.18 The polarization curves of an anion exchange membrane water electrolyzer operating at 298 K and atmospheric pressure with the Ir Turing catalyst of Example 1 as cathode and anode catalysts are shown. DETAILED DESCRIPTION

[0051] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0052] Example 1

[0053] This embodiment provides a Turing catalyst, which is prepared by the following steps:

[0054] A Si film is deposited on a Si (001) substrate as a buffer layer, wherein the purity of Si is 99.999%;

[0055] The magnetron sputtering technology was used to co-sputter Pt or Ir (purity of 99.95 at.%) target and Zn target (purity of 99.999 at.%) at a film deposition rate of 10 nm / min to form a metal film layer; wherein the ratio of Pt to Zn was 4:1; the thickness of the metal film layer was 20 nm, wherein the base pressure before deposition was 2.0×10 -6 torr, and the argon pressure during deposition was 3×10-3 torr.

[0056] After sputtering, the metal film layer was placed on N 2 The samples were chemically treated in a purified 0.1 M KOH aqueous solution for 60 minutes; thereafter, the samples were heated in a water bath at 40°C for 60 minutes; the samples were then washed four times in pure water and anhydrous ethanol to remove residual chemicals; and then centrifuged at 5000 rpm for 5 minutes to collect the resulting Turing catalysts, namely platinum Turing catalysts and iridium Turing catalysts.

[0057] The Turing catalyst was ultrasonically treated in anhydrous ethanol at 273 K for 60 minutes to obtain a uniform catalyst ink.

[0058] Comparative Example 1

[0059] Platinum nanosheets (Pt nanosheets) and iridium nanosheets (Ir nanosheets) were prepared by magnetron sputtering, with thicknesses of 10 nm and 10 nm respectively.

[0060] Comparative Example 2

[0061] Pt foil and Ir foil. The thickness of the Pt foil is 10 nm; the thickness of the Ir foil is 10 nm.

[0062] Comparative Example 3

[0063] Pt / C catalyst, Ir / C catalyst, IrO x The catalysts were purchased from Premetek, USA. 2 It is a standard sample for testing.

[0064] Test method:

[0065] (1) Material characterization

[0066] TEM analysis, electron diffraction analysis and energy dispersive X-ray spectroscopy were performed on a JEM2100FFEG transmission electron microscope with an accelerating voltage of 200 kV.

[0067] Fast Fourier transform and lattice spacing analysis were performed in Digital Micrograph software.

[0068] X-ray diffractometer (Smartlab, Rigaku, Japan) using Cu Kα radiation The crystal structure of the Turing catalyst was determined using an X-ray photoelectron spectrometer (PHI Model 5802, PHI, USA) with Al Kα X-ray radiation to study the valence state and composition.

[0069] The binding energy of the XPS spectra was calibrated with reference to the C1s peak at 284.8 eV.

[0070] The exact chemical composition of the Turing catalyst was determined by ICP-OES (Optima 8000, PerkinElmer, USA).

[0071] The L-edge X-ray absorption spectra of platinum and iridium were recorded at the BL11B beamline of the Shanghai Synchrotron Radiation Facility (SSRF).

[0072] XAFS data were collected in transmission mode using an argon-filled Lytle ionization chamber (EXAFS Inc.). The beam current of the storage ring was 200 mA in uplink mode. The incident photons were monochromatized by a Si(111) double crystal monochromator with an energy resolution of ΔE / E ∼ 1.4 × 10 -4 The spot size on the sample is ~200μm×250μm. The energy at the absorption edge (E 0 ) was calibrated with metal foil. The XAFS data were processed using Athena (version 0.9.26) and Artemis (version 0.9.26) software. When fitting the XAFS data of Pt foil and Ir foil, The k range uses k3 weighting, and the R range is When fitting the XAFS data of the Pt sample, the The k range and When fitting the XAFS data of the Ir sample, the The k range and In the wavelet transform analysis, χ(k) exported from Athena was imported into the HAMAFortran code. The parameters of the analysis were the R range of the samples The range of k is The k weight is 3, and the Morlet function with κ = 10 and σ = 1 is used as the mother wavelet to obtain the overall distribution.

[0073] (2) Electrochemical test

[0074] The electrochemical tests were performed on a CHI 660E electrochemical workstation (CH Instruments, USA) connected to a three-electrode electrochemical cell using a carbon rod as the counter electrode and the reference electrode being Hg / HgO in alkaline electrolytes or a saturated calomel electrode in acidic electrolytes.

[0075] The prepared catalyst ink was dropped onto a carbon cloth (6.5 mm × 10.0 mm) and connected to an electrochemical workstation as a working electrode. Argon-saturated KOH or H 2 SO 4 The solution was used as electrolyte. All measurements were performed at room temperature.

[0076] All LSV curves were recorded in 1.0 M KOH electrolyte at a scan rate of 5 mV s -1 , with 85% ohmic drop compensation. Cdl was measured by CV with a scan rate of 10-100mV s -1 The HER stability test was performed by scanning the potential in the non-Faraday overpotential range at 200 mVs -1 The CV cycles were repeated for 30,000 times at a scan rate of 200 mV s, and the LSV curves before and after the scan were compared. For OER, the LSV curves were repeated for 15,000 times in the potential range of 1.23 to 1.65 V (vs. RHE), and the LSV curves before and after the scan were compared. The scan rate was 200 mV s -1 .

[0077] The copper potential underdeposition (UPD) test was carried out as follows: after electrochemical cleaning, the copper was deposited in an aqueous solution containing 5 mM CuSO 4 0.1MH electrolyte 2 SO 4 The catalyst was polarized at 0.3 V (vs. RHE) for 700 s; then 2 SO 4 10mV s -1 The stripping cycle data of copper were collected at a scan rate of . The electrochemically active surface area (ECSA) of Pt Turing catalyst, Pt nanosheets and Pt / C was calculated using the underpotential deposition-stripping CV curves of copper and the following formula:

[0078]

[0079] Where Q Cu (mC) is the Cu upd stripping process on the CV curve (0.3-0.8V vs.RHE, Cu upd →Cu 2+ +2e - ), which is the area under the Cu upd stripping peak minus the area under the double layer and the scan rate (10 mV s -1 ) ratio. 0.42mC cm -2 The value of is the charge associated with the monolayer adsorption of copper atoms on Pt, and [Pt] is the loading of Pt on the working electrode.

[0080] The H-based kinetics of Ir Turing catalyst, Ir nanosheets, and Ir / C were calculated based on the CV curves and the following formula: upd ECSA value:

[0081]

[0082] Among them, Q H (mC) is the average charge integrated from 0.05 to 0.4 V on the CV curve, which is determined by H upd The area under the peak minus the double layer and the scanning speed (10 mV s -1 ) ratio. 0.21mC cm -2 The value of is based on the assumption that each Ir surface atom has one electron transferred charge, and [Ir] is the Ir loading on the working electrode.

[0083] (3) Assembly and testing of membrane electrode reactor

[0084] The Turing catalyst was integrated into a membrane electrode reactor to construct an AEM water electrolyzer device and its electrochemical performance was evaluated using an Autolab PGSTAT 302N. The anion exchange membrane Sustainion X37-50 (Dioxide Materials, USA) was soaked in 1.0 M KOH solution for at least 48 h before being used in the MEA. The catalyst ink was prepared by uniformly distributing the catalyst into a mixture of ethanol and ionomer solution under ultrasonic treatment at 0 °C for approximately 1 h. Afterwards, the catalyst ink was sprayed on carbon paper as the cathode catalyst with an exposed surface area of ​​1 cm2 at 60 °C; the catalyst mass loading on the cathode was approximately 0.05 mg PGM cm -2 Under the same conditions, Turing Ir ink was sprayed on platinum-coated titanium felt as the anode catalyst. In the control group, Pt / C and IrO x They were used as catalysts for the cathode and anode, respectively. Carbon paper coated with catalysts and platinum-coated titanium felt were used as catalyst layers and gas diffusion layers for the cathode and anode, respectively. The cathode part, the anode part and the prepared anion exchange membrane were integrated into an AEM water electrolyzer device, and the water electrolysis performance of the device was evaluated. In addition, the flow field was sealed with an insulating gasket to prevent leakage of liquids and gases. At room temperature, a 1.0M KOH electrolyte was circulated through both sides of the cathode and anode using a peristaltic pump. The polarization curve was obtained from a voltage range of 1.2 to 2.0V at atmospheric pressure at 25°C. The stability test was carried out using a constant current method at a constant current of 0.5A and room temperature. Before obtaining the stability curve, the constant current test was carried out for 30 minutes to reach a steady state. In the present invention, a metal Turing structure catalyst is provided, and its schematic diagram is shown as follows Figure 1As shown. Turing structures are usually formed in reaction-diffusion systems, where the different diffusion rates of activators and inhibitors lead to preferential growth. When extending Turing structures into homogeneous solutions with inappropriate reactant diffusivities, activators are designed to be bound by macromolecules or spatially confined in specific phases, such as interfacial aggregation of low-solubility activators in water and nanopore confinement. Therefore, ultrathin films are conducive to the occurrence of selective etching, facilitating the formation of Turing-type structures.

[0085] Figure 2 Figures a and b show TEM images of Pt Turing catalyst and Ir Turing catalyst, respectively. It can be seen from the figure that the Turing catalyst of the present invention has a nearly two-dimensional (2D) nanonet with a maze-like pattern. These ultrafine nanonets are composed of twisted stripes and Y-shaped forks, which unify irregular chains to form a continuous network. This maze-like topological structure with broken symmetry characteristics is consistent with the characteristics of the Turing structure. Figure 2 In c, a TEM image of a single platinum planar nanosheet (with a thickness of 10 nm) is given. Figure 2 Comparison of a to c shows that the structures of the Turing catalyst of the present invention and the non-Turing metal nanosheets are significantly different.

[0086] Depend on Figure 3 A shows an image of a platinum Turing catalyst under a high-resolution transmission electron microscope (HRTEM). It can be seen that the Turing catalyst of the present invention is composed of extremely fine nanocrystals with random orientations, and there are a large number of nanotwins and multiple twins with parallel twin boundaries in the bifurcation region. Figure 3 In b, we can see that the Fourier transform diffraction pattern (FFT) of these nanotwins includes {111} and {200} diffraction spots along the

[011] zone axis. The coherent twin boundary is on the {111} plane, while some twin subunits do not completely coincide with the twin plane due to the insertion of two or three layers of stacking faults (called incoherent twin boundaries). Figure 3 As shown in c, the twin boundary density of the Pt Turing catalyst is estimated to be 21.4 μm -1 , is a platinum nanosheet (1.7 μm -1 ) is 12.6 times.

[0087] Figure 4 a, Figure 4 Figure b shows an HRTEM image of an Ir Turing catalyst with a high density of twin boundaries. It can be seen that the Ir Turing catalyst has structural features similar to those of the Pt Turing catalyst. The corresponding TB density is measured to be 34.3 μm -1 , which is 14.3 times that of Ir nanosheets.

[0088] Depend on Figure 3 Middle a, Figure 3Middle b, Figure 3 Middle c, Figure 4 A and Figure 4 As can be seen from b, the high-density twin boundaries are the symbiotic characteristics of the Turing catalyst in the present invention.

[0089] Figure 5 The twin boundary densities of the Pt Turing catalyst, Pt nanosheets, Ir Turing catalyst, and Ir nanosheets are shown.

[0090] Furthermore, the present invention performs X-ray absorption spectroscopy analysis to analyze the local atomic and electronic structure of the Turing-type catalyst. The valence states of Pt and Ir can be derived from the intensity of the white lines in the X-ray absorption near edge structure (XANES) spectrum. Figure 6 It can be seen that the intensity of the white line peak of the platinum L3 edge of the platinum Turing catalyst and platinum nanosheets is slightly higher than that of the platinum foil, but much lower than that of platinum dioxide, which indicates that the average valence state of platinum in the Turing-type catalyst and platinum nanosheets is close to zero.

[0091] Furthermore, the present invention performs extended X-ray absorption fine structure (EXAFS) spectroscopy to reveal information about the coordination structure and coordination number (CN). Figure 7 The EXAFS spectrum of the platinum Turing catalyst shows that there is only one prominent peak at This originates from the first-shell Pt-Pt bond; this length is longer than the Pt-Pt bond length in platinum foil ( Figure 7 The CN value is calculated by fitting the Pt-Pt first shell in Fourier transform EXAFS spectroscopy. Figure 7 As shown in Figure c, the CN of these samples decreases in the order of Pt foil (12), Pt nanosheets (10.1), and Pt Turing catalyst (7.2). The obvious decrease in CN of the Pt Turing catalyst indicates that its specific surface area is very large, of which the exposed low-coordinated surface atoms account for a large proportion. In addition to the contribution of Turing morphology to the decrease in CN, the low-coordinated atoms on twin boundaries and stacking faults also lead to low CN values. For the Ir Turing catalyst, there is a single main peak related to the first shell Ir-Ir bond in the EXAFS spectrum. ( Figure 7 b), including Ir foil (12), Ir two-dimensional nanosheets (9.8), and Ir Turing catalyst (6.5; Figure 7 The CN of samples including those in (c) showed a similar decrease.

[0092] The results were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) and X-ray photoelectron spectroscopy (XPS, Figure 8) showed that the metal (Pt, Ir) of the first metal target was the main element, and these samples contained almost no Al element, indicating that a nanomaterial with a simple composition was formed.

[0093] The polarization curves of the Pt Turing catalyst of Example 1, the Pt nanosheets of Comparative Example 1, and the Pt / C catalyst of Comparative Example 3 are as follows: Fig. 9 shown.

[0094] The Tafel slope (left axis) and mass activity (right axis) of the Pt Turing catalyst of Example 1, the Pt nanosheet of Comparative Example 1, and the Pt / C catalyst of Comparative Example 3 are shown in Figure 2. Fig.10 shown.

[0095] The polarization curves obtained before and after cyclic voltammetry of the Pt Turing catalyst of Example 1 and the Pt / C catalyst of Comparative Example 3 are as follows: Fig.11 shown.

[0096] The polarization curves of the Pt Turing catalyst of Example 1 and the Pt / C catalyst of Comparative Example 3 at 298K and atmospheric pressure in an anion exchange membrane water electrolyzer using a PtIr mesh as an anode catalyst are as follows: Fig.12 shown.

[0097] The chronoamperometric test curve of the Pt Turing catalyst of Example 1 at 298K and atmospheric pressure in an anion exchange membrane water electrolyzer using a PtIr mesh as an anode catalyst is as follows: Fig.13 shown.

[0098] The hydrogen evolution performance polarization curves of the Ir Turing catalyst of Example 1, the Ir nanosheets of Comparative Example 1, and the Ir / C catalyst of Comparative Example 3 are shown in FIG. Fig.14 shown.

[0099] The Ir Turing catalyst of Example 1, the Ir nanosheet of Comparative Example 1, the Ir / C catalyst of Comparative Example 3, and the IrO x The hydrogen evolution mass activity (left axis) and oxygen evolution mass activity (right axis) of the catalyst are shown in Fig.15 shown.

[0100] The Ir Turing catalyst of Example 1, the Ir / C catalyst of Comparative Example 3, and the IrO x The oxygen evolution polarization curve of the catalyst is shown in Fig.16 shown.

[0101] The electrochemical double layer capacitance of the Ir Turing catalyst of Example 1, the Ir nanosheet of Comparative Example 1, and the Ir / C catalyst of Comparative Example 3 is as follows: Fig.17 shown.

[0102] The polarization curve of the anion exchange membrane water electrolyzer using the Ir Turing catalyst of Example 1 as the cathode and anode catalyst at 298K and atmospheric pressure is shown in Fig.18 shown.

[0103] The performance of the embodiments and comparative examples is shown in Table 1.

[0104] Table 1

[0105]

[0106] It can be seen from the above embodiments that the Turing catalyst of the present invention has a unique topological structure, a large specific surface area and an intrinsic microstructural optimization of high-density twin boundaries. In view of this, the Turing catalyst of the present invention has excellent catalytic performance with low overpotential and high mass activity.

[0107] The simple Pt and Ir water splitting nanocatalyst successfully achieved higher mass activity, which shows the possibility of the composition of high-performance nanocatalysts, which can be adjusted by topological structure and crystal defects instead of complex multi-element composition. Thus, the present invention can solve the problem of poor recyclability and sustainability of scarce precious metals in the prior art.

[0108] In addition, the Turing catalyst of the present invention has excellent stability. After 30,000 cycles, the polarization curve of the Pt Turing catalyst almost overlaps with the polarization curve measured initially. The timing test also shows that the long-term stability of the Turing platinum-based electrolyzer is excellent.

[0109] The Turing catalyst of the present invention is suitable for electrolytic water catalysis and has excellent hydrogen evolution activity. When the Ir Turing catalyst is used, it also has excellent oxygen evolution activity. The catalyst of the present invention has high reusability and high stability and has broad application prospects.

Claims

1. A method for preparing a Turing catalyst, in, The preparation method comprises: By sputtering the M target and the N target together, a MN film is deposited on the surface of the substrate; Wherein, M is one or a combination of two or more of Ru, Os, Rh, Ir, Pd, Pt, Ag, and Au; Wherein, the N is one or a combination of two or more of Zn, Si, Al, and Pb; The MN film is placed in an alkaline solution for etching to obtain the Turing catalyst.

2. The preparation method according to claim 1, in, The preparation method comprises the following specific steps: Depositing a buffer layer on the substrate, and then depositing the MN film on the surface of the buffer layer; Preferably, the material of the buffer layer is one of Si, Zn, Sn, Al and Pb.

3. The preparation method according to claim 1, in, The thickness of the MN film is 1-20 nm, preferably 6 nm.

4. The preparation method according to claim 1, in, The solute in the alkaline solution includes NaOH and / or KOH; Preferably, the concentration of the alkaline solution is 0.1 to 6 M, more preferably 0.1 M; Preferably, after the etching is completed, the etched sample is heat treated at 40-95° C. for 10-90 min, followed by washing and centrifugation to obtain the Turing catalyst. 5 . The preparation method according to claim 1 , in the MN film, in terms of atomic percentage, the percentage of M is 15 to 80 at. %, and the percentage of N is 20 to 85 at. %.

6. The preparation method according to claim 1, in, The deposition is physical vapor deposition; Preferably, the deposition rate of the physical vapor deposition is 1 nm to 10 nm per minute, measured in terms of the thickness of the MN film; Preferably, the base pressure before deposition is 1.0×10 -6 ~9.0×10 -6 torr, and the argon pressure during deposition was 1×10 -3 ~12×10 -3 torr.

7. A Turing catalyst obtained by the preparation method according to any one of claims 1 to 6.

8. Use of the Turing catalyst according to claim 7 in electrolysis of water.

9. A membrane electrode reactor, in, The cathode and anode of the membrane electrode reactor are respectively prepared from the Turing catalyst described in claim 7.

10. The membrane electrode reactor according to claim 9, in, The cathode and anode are prepared in the following manner: placing the Turing catalyst in a mixture of ethanol and ionomer solution and subjecting it to ultrasonic treatment to obtain catalyst ink; Spraying the catalyst ink onto carbon paper to obtain the cathode; The anode is obtained by spraying catalyst ink onto platinum-coated titanium felt.

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