Process for the preparation and use of metal diatomic polymer catalysts

Abstract

The present application relates to the technical field of catalyst material preparation, and discloses a metal diatomic polymer catalyst and a preparation method thereof, wherein the metal diatomic polymer catalyst is composed of a polymer obtained by the reaction of monomer one and monomer two, and a complex metal ion, the monomer one is an aromatic monomer containing a mercapto group and an aldehyde group or an aromatic monomer containing a hydroxyl group and an aldehyde group, and the monomer two is an aromatic tetraamine or hexamine monomer.The present application has the beneficial effect that the aldehyde group of the monomer one and the amino group of the monomer two can form a polymer connected by aromatic rings through Schiff base reaction, and the polymer is further complexed with a metal ion, the metal ion is coordinated with two nitrogen atoms on the Schiff base structure and two oxygen atoms from the ionized phenolic hydroxyl group or two sulfur atoms on the mercaptobenzene, forming a diatomic polymer composed of a planar structural unit of [MaMbN4X2] or [MaMbN4X4], X is an O atom or an S atom, the polymer has a linear long-chain structure or a planar structure, the structure is regular, and a plurality of metal atoms can be anchored.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalytic material preparation, in particular to a metal diatomic polymer catalyst and a preparation method and application thereof. BACKGROUND

[0002] Since ancient times, energy has played a very important role in human development. People's eating, wearing, using, living, traveling and agricultural production activities cannot be separated from energy. Due to the exploitation and use of fossil fuels, environmental problems have become increasingly serious. Therefore, developing and efficiently using pollution-free sustainable energy is an effective way to solve the above problems.

[0003] For example, fuel cells, metal-air batteries and many other energy sources can provide energy, and in the process of use, they are environmentally friendly, energy efficient, and widely used, and are concerned. During the operation of these batteries, the energy generated depends on the reaction occurring at both poles. For example, the oxygen reduction reaction (ORR) as an important cathode reaction in fuel cells and metal-air batteries has the disadvantage of slow reaction kinetics due to multi-stage reaction and slow reaction, low material transport efficiency, etc. Therefore, it needs a high-activity catalyst to reduce the reaction barrier, optimize the adsorption and desorption of intermediates, etc. to enhance the reaction. Compared with traditional single-atom catalysts, diatomic catalysts have higher catalytic activity and reaction stability, which can more favorably catalyze the reaction, and therefore have better application prospects.

[0004] A Chinese invention patent with publication number CN115704097A discloses a preparation method and use of a diatomic catalyst with a MaMb-support structure, which uses a binuclear complex as a precursor and is loaded on a support to obtain a high-temperature pyrolysis under an inert atmosphere; wherein the catalytically active sites Ma and Mb are loaded on the support in an atomic state, the distance between the two metal atoms is 2-4 Å, and the support is a carbon-based support or a metal oxide. The application discloses a technical solution for atomic-level dispersion of two metal atoms, but this technical solution can only control the distance between the two metal atoms in the same binuclear complex. In addition, the diatomic catalyst in this application is obtained by loading multiple small-molecule binuclear complexes on a support and high-temperature pyrolysis, and in the high-temperature pyrolysis process, the metal tends to agglomerate, making it impossible to accurately control the spacing between each complex and the complex. In addition, the application mentioned in this application is the synthesis of small-molecule complexes, and therefore does not have the structural characteristics of long-chain order of macromolecular polymers. SUMMARY

[0005] The present application aims to control the spacing between metal atoms in a metal diatomic polymer catalyst, and proposes a preparation method and application of a metal diatomic polymer catalyst to address the above deficiencies in the prior art.

[0006] A metal diatomic polymer catalyst is formed by a complex of metal ions and a polymer obtained by reacting monomer one and monomer two, wherein the monomer one is an aromatic monomer containing a thiol group and an aldehyde group or an aromatic monomer containing a hydroxyl group and an aldehyde group, and the monomer two is an aromatic tetraamine or hexamine monomer.

[0007] The aromatic monomer one containing a hydroxyl group and an aldehyde group is one of 2-hydroxyisophthalaldehyde, 1,8-dihydroxy-2,7-naphthalene dicarboxaldehyde and 1,9-dihydroxy-2,8-anthracene dicarboxaldehyde, and the aromatic monomer one containing a thiol group and an aldehyde group is one of 1,3-benzenedicarboxaldehyde-2-thiol, 1,8-dimercapto-2,7-naphthalene dicarboxaldehyde and 1,9-dimercapto-2,8-anthracene dicarboxaldehyde.

[0008] The aromatic tetraamine or hexamine monomer two is one of 1,2,4,5-benzene tetramine, 2,3,6,7-tetraaminonaphthalene, anthracene-2,3,6,7-tetramine, 4,5,9,10-tetraaminopyrene and 2,3,6,7,10,11-hexaaminotriphenyl.

[0009] The metal is one or more of Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Ru, Rh, Pd, Ir, Pt, Ag and Au.

[0010] A preparation method of a metal diatomic polymer catalyst, characterized in that the method comprises the following steps:

[0011] S1, mixing a methanol solution of monomer one with a methanol solution of metal ions to obtain a mixed solution;

[0012] S2, slowly adding a methanol solution of monomer two to the mixed solution obtained in step S1, and performing condensation reflux until crystals are precipitated;

[0013] S3, filtering, washing and drying the crystals obtained in step S2 to obtain a homometallic diatomic polymer M-DP.

[0014] When the monomer two is a tetraamine monomer, the molar ratio of the monomer one, the tetraamine monomer two and the metal ions is (1.8-2.2):1:(1.8-2.2); when the monomer two is a hexamine monomer, the molar ratio of the monomer one, the hexamine monomer two and the metal ions is (2.8-3.2):1:(2.8-3.2).

[0015] A preparation method of a metal diatomic polymer catalyst, characterized in that the method comprises the following steps:

[0016] S1, mixing the methanol solution of monomer one with the methanol solution of metal Ma, and uniformly mixing to obtain a mixed solution;

[0017] S2, slowly dropping the methanol solution of monomer two into the mixed solution obtained in step S1, and condensing reflux until crystals are precipitated;

[0018] S3, filtering, washing and drying the crystals obtained in step S2 to obtain an atomic polymer Ma-P' complexed with metal Ma;

[0019] S4, dispersing Ma-P' obtained in step S3 in a methanol solution to form a Ma-P' methanol mixed solution, slowly dropping a methanol solution containing metal Mb into the Ma-P' methanol mixed solution, and reacting to form a mixture;

[0020] S5, when the color of the mixture in step S4 is unchanged, adding a methanol solution of monomer two, and after the reaction is completed, filtering, washing and drying the obtained precipitate to obtain a hetero-bimetallic atomic polymer MaMb-DP.

[0021] The above technical solution is further provided as follows: when the monomer two is a tetraamine monomer, the molar ratio of the monomer one in step S1, the tetraamine monomer two in step S2 and the tetraamine monomer two in step S5 is (3.8-4.2):1:1, and the molar ratio of the monomer one, the metal Ma and the metal Mb is (3.8-4.2):(1.8-2.2):(1.8-2.2); when the monomer two is a hexamine monomer, the molar ratio of the monomer one in step S1, the hexamine monomer two in step S2 and the hexamine monomer two in step S5 is (5.8-6.2):1:1, and the molar ratio of the monomer one, the metal Ma and the metal Mb is (5.8-6.2):(2.8-3.2):(2.8-3.2).

[0022] The metal bimetallic atomic polymer catalyst material uses a matrix material as a carrier, and a polymer catalyst with metal atoms loaded on the surface.

[0023] The above technical solution is further provided as follows: the matrix material includes one or more of conductive carbon black, carbon nanotubes, activated carbon, Ketjen black, graphene, carbon cloth, carbon fiber, cotton fabric, polyester, nylon, wool, silk, glass fiber cloth, aramid fiber cloth, and polypropylene.

[0024] The beneficial effects of the present application are as follows:

[0025] 1. The aldehyde group and hydroxyl / mercapto-containing aromatic monomer one and aromatic tetraamine or hexamine monomer two undergo Schiff base reaction to form a polymer connected by aromatic rings, which is further complexed with metal ions, the metal ions are coordinated with two nitrogen atoms on the Schiff base structure and two oxygen atoms from the ionized phenolic hydroxyl group or two sulfur atoms on the mercaptobenzene, forming a metal biatomic linear or planar polymer composed of [MaMbN4X2] or [MaMbN4X4] planar structural units, X is O atom or S atom. Since the pyrolysis-free strategy is adopted in the whole synthesis process of the polymer, the polymer has the originally designed linear or planar long-chain structure, and the structure is regular, and can anchor multiple metal atoms.

[0026] 2. In the catalytic reaction process, the catalytic material needs to have suitable adsorption capacity for the reaction intermediates (such as O, OOH, OH in the catalytic ORR process). If the adsorption capacity of the catalytic material is too strong, the catalytic product will be adsorbed on the catalytic material and is not easy to remove, which occupies the active sites and reduces the subsequent catalytic efficiency; if the adsorption capacity of the catalytic material is too weak, the catalytic material cannot play a catalytic role. The present application adjusts the distance between the metal biatoms in the repeating unit of the polymer or adjusts the distance between the adjacent two repeating units by changing the type of monomer one or monomer two, so as to optimize the adsorption and desorption capacity of the catalytic material for the intermediates in the whole reaction process, thereby improving the catalytic performance of the metal atom catalytic material, reducing the reaction energy barrier, and promoting the reaction.

[0027] 3. The synthesized metal atom polymer catalyst can be compounded with different carriers according to different needs to obtain different metal atom polymer catalyst materials. The polymer can be synthesized in situ on the carrier, and the whole preparation process does not need pyrolysis, and the active sites are well preserved.

[0028] 4. By changing the type of monomer two, the distance between the adjacent two [MaMbN4X2] or [MaMbN4X4] planar structures in the metal biatomic polymer can be adjusted, and the distance between the adjacent two [MaMbN4X2] or [MaMbN4X4] planar structures will affect the catalytic performance of the metal biatom. By selecting a suitable monomer two, the catalytic performance of the metal biatom in the [MaMbN4X2] or [MaMbN4X4] planar structure can be further adjusted. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the present application, the drawings used in the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0030] Figure 1 FIG. 4 is a transmission electron microscope scanning image of the S-Co@CNT catalyst in Embodiment 4; Figure 1 a is a transmission electron microscope scanning image of the S-Co@CNT catalyst in Embodiment 4, Figure 1 b is a transmission electron microscope scanning image of the L-Co@CNT catalyst in Embodiment 5;

[0031] Figure 2 FIG. 5 is a spherical aberration correction transmission electron microscope scanning image of the S-Co@CNT catalyst in Embodiment 4;

[0032] Figure 3 FIG. 6 is a linear scan voltammetry curve of the catalysts in Embodiments 4-5 and a commercial Pt / C catalyst in 0.1 M KOH electrolyte;

[0033] Figure 4 FIG. 7 is a hydrogen peroxide yield and electron transfer number of the catalysts in Embodiments 4-5 and a commercial Pt / C catalyst in 0.1 M KOH electrolyte. DETAILED DESCRIPTION

[0034] The following are specific embodiments of the present application and further describe the technical solutions of the present application in combination with the drawings, but the present application is not limited to these embodiments.

[0035] A preparation method of a metal diatomic polymer catalyst, characterized in that the method comprises the following steps, in terms of mole fraction:

[0036] S1, mixing 1.8-3.2 parts of a methanol solution of monomer one and 1.8-3.2 parts of a methanol solution of metal ions, and uniformly mixing to obtain a mixed solution;

[0037] S2, slowly adding 1 part of a methanol solution of monomer two to the mixed solution obtained in step S1, and condensing and refluxing until crystals are precipitated;

[0038] S3, filtering, washing and drying the crystals obtained in step S2 to obtain a homometallic diatomic polymer M-DP.

[0039] The monomer one is one of 2-hydroxyisophthalaldehyde, 1,8-dihydroxy-2,7-naphthalene dicarboxaldehyde, 1,9-dihydroxy-2,8-anthracene dicarboxaldehyde, 1,3-benzenedicarboxaldehyde-2-mercapto, 1,8-dimercapto-2,7-naphthalene dicarboxaldehyde, and 1,9-dimercapto-2,8-anthracene dicarboxaldehyde.

[0040] 1,3-benzenedicarboxaldehyde-2-mercapto, 1,8-dimercapto-2,7-naphthalene dicarboxaldehyde, 1,9-dimercapto-2,8-anthracene dicarboxaldehyde are prepared from the corresponding 2-hydroxyisophthalaldehyde, 1,8-dihydroxy-2,7-naphthalene dicarboxaldehyde, 1,9-dihydroxy-2,8-anthracene dicarboxaldehyde, the reaction mechanism of preparation is as follows:

[0041]

[0042] The monomer two is one of 1,2,4,5-benzene tetramine, 2,3,6,7-tetraaminonaphthalene, anthracene-2,3,6,7-tetramine, 4,5,9,10-tetraaminopyrene, 2,3,6,7,10,11-hexaaminotriphenyl.

[0043] 2-hydroxyisophthalaldehyde is used as monomer one, 1,2,4,5-benzene tetramine is used as monomer two, and a homometallic atomic polymer M-DP is prepared, and the reaction equation is as follows formula 1:

[0044]

[0045] 1,3-benzenedicarboxaldehyde-2-mercapto is used as monomer one, 1,2,4,5-benzene tetramine is used as monomer two, and a homometallic atomic polymer M-DP is prepared, and the reaction equation is as follows formula 2:

[0046]

[0047] 1,8-dihydroxy-2,7-naphthalene dicarboxaldehyde is used as monomer one, 1,2,4,5-benzene tetramine is used as monomer two, and a homometallic atomic polymer M-DP is prepared, and the reaction equation is as follows formula 3:

[0048]

[0049] 1,8-dimercapto-2,7-naphthalene dicarboxaldehyde is used as monomer one, 1,2,4,5-benzene tetramine is used as monomer two, and a homometallic atomic polymer M-DP is prepared, and the reaction equation is as follows formula 4:

[0050]

[0051] 1,9-dihydroxy-2,8-anthracene dicarboxaldehyde is used as monomer one, 1,2,4,5-benzene tetramine is used as monomer two, and a homometallic atomic polymer M-DP is prepared, and the reaction equation is as follows formula 5:

[0052]

[0053] The homometallic diatomic polymer M-DP is prepared by using 1,9-dimercapto-2,8-anthracene-dimethanol as monomer one and 1,2,4,5-benzene tetramine as monomer two, and the reaction equation is as shown in the following formula 6.

[0054]

[0055] As can be seen from the formula 1 to formula 6, by changing the monomer one, the distance between the two metal atoms in the [M2N4X2] or [M2N4X4] structural unit of the polymer can be controlled.

[0056] The homometallic diatomic polymer M-DP is prepared by using 2-hydroxy-m-xylylene glycol as monomer one and 2,3,6,7-tetraaminonaphthalene as monomer two, and the reaction equation is as shown in the following formula 7.

[0057]

[0058] The homometallic diatomic polymer M-DP is prepared by using 1,3-benzene dimethyl-2-mercapto as monomer one and 2,3,6,7-tetraaminonaphthalene as monomer two, and the reaction equation is as shown in the following formula 8.

[0059]

[0060] The homometallic diatomic polymer M-DP is prepared by using 2-hydroxy-m-xylylene glycol as monomer one and anthracene-2,3,6,7-tetramine as monomer two, and the reaction equation is as shown in the following formula 9.

[0061]

[0062] The homometallic diatomic polymer M-DP is prepared by using 1,3-benzene dimethyl-2-mercapto as monomer one and anthracene-2,3,6,7-tetramine as monomer two, and the reaction equation is as shown in the following formula 10.

[0063]

[0064] As can be seen from the formula 1, formula 2, formula 7 to formula 10, by changing the monomer two, the distance between the metal atoms of the adjacent two structural units in the polymer can be controlled.

[0065] The homometallic diatomic polymer M-DP is prepared by using 2-hydroxy-m-xylylene glycol as monomer one and 2,3,6,7,10,11-hexaaminotriphenyl as monomer two, and the reaction equation is as shown in the following formula 11.

[0066]

[0067] A homometallic atomic polymer M-DP is prepared by using 1,3-benzene dicarboxaldehyde-2-mercapto as monomer one and 2,3,6,7,10,11-hexamino triphenyl as monomer two, and the reaction equation is shown in formula 12.

[0068]

[0069] As can be seen from formula 11 and formula 12, the aromatic hexamine is used as monomer two, and a metal double-atom planar polymer can be obtained.

[0070] The preparation method of the metal double-atom polymer catalyst, characterized in that, comprising the following steps, in terms of mole fraction:

[0071] S1, a methanol solution containing 3.8-6.2 parts of monomer one is mixed with a methanol solution containing 1.8-3.2 parts of metal Ma, and the mixture is uniformly obtained;

[0072] S2, a methanol solution containing 1 part of monomer two is slowly added to the mixture obtained in step S1, and condensation reflux is carried out until crystals are precipitated;

[0073] S3, the crystals obtained in step S2 are filtered, washed and dried to obtain an atomic polymer Ma-P' complexed with metal Ma;

[0074] S4, the Ma-P' obtained in step S3 is dispersed in a methanol solution to form a Ma-P' methanol mixture, and a methanol solution containing 1.8-3.2 parts of metal Mb is slowly added to the Ma-P' methanol mixture, and a mixture is formed by reaction;

[0075] S5, when the color of the mixture in step S4 is unchanged, 1 part of monomer two in methanol solution is added, and after the reaction is completed, the obtained precipitate is filtered, washed and dried to obtain a heterometallic atomic polymer MaMb-DP.

[0076] A heterometallic atomic polymer M-DP is prepared by using 2-hydroxy m-benzene dicarboxaldehyde as monomer one and 1,2,4,5-benzene tetramine as monomer two, and the reaction equation is shown in formula 13.

[0077]

[0078] A heterometallic atomic polymer M-DP is prepared by using 1,3-benzene dicarboxaldehyde-2-mercapto as monomer one and 1,2,4,5-benzene tetramine as monomer two, and the reaction equation is shown in formula 14.

[0079]

[0080] In step S1, the molar ratio of monomer one and monomer two is close to 4:1, 1 mole of monomer two can react with 4 moles of monomer one to first generate a small molecule compound as shown in formula 13 or formula 14, each small molecule compound contains 4 vacancies that can complex metal atoms, 2 moles of metal Ma are added to the small molecule compound, the metal Ma first occupies two vacancies in the small molecule compound as shown in formula 13 or formula 14 to form two [MaN2X2O2] structures, X is an O atom or an S atom, because the energy required for the metal Ma to enter another vacancy in the [MaN2X2O2] structure is higher, so the metal ion preferentially forms a single metal atom polymer Ma-P'.

[0081] Then 2 moles of a methanol solution of metal Mb are slowly added to the single metal atom polymer Ma-P', as shown in formula 13 or formula 14, the metal Mb will complex with another vacancy in the [MaN2X2O2] structure to obtain a small molecule compound containing two [MaMbN2X2O2] structures.

[0082] In step S5, 1 part of monomer two is further added to the mixture, and the monomer two can connect the small molecule compounds containing two [MaMbN2X2O2] structures in step S4 to each other to obtain one large molecule polymer with a structure of [MaMbN4X2].

[0083] A hetero-bimetallic atom polymer M-DP is prepared by using 2-hydroxyisophthalaldehyde as monomer one and 2,3,6,7,10,11-hexaaminotriphenyl as monomer two, and the reaction equation is as follows formula 15:

[0084]

[0085] A hetero-bimetallic atom polymer M-DP is prepared by using 1,3-benzenedimethanol-2-mercapto as monomer one and 2,3,6,7,10,11-hexaaminotriphenyl as monomer two, and the reaction equation is as follows formula 16:

[0086]

[0087] In step S1, the molar ratio of monomer one and monomer two is close to 6:1, 1 mole of monomer two can react with 6 moles of monomer one to first generate a small molecule compound as shown in formula 15 or formula 16, each small molecule compound contains 6 vacancies that can complex metal atoms, 3 moles of metal Ma are added to the small molecule compound, the metal Ma first occupies three vacancies in the small molecule compound as shown in formula 15 or formula 16 to form three [MaN2X2O2] structures, X is an O atom or an S atom, because the energy required for the metal Ma to enter another vacancy in the [MaN2X2O2] structure is higher, so the metal ion preferentially forms a single metal atom polymer Ma-P'.

[0088] Then, 3 molar parts of methanol solution of metal Mb, as shown in formula 15 or formula 16, is slowly added to the single metal atom polymer Ma-P', and the metal Mb is complexed with another vacancy in the [MaN2X2O2] structure to obtain a small molecule compound containing three [MaMbN2X2O2] structures.

[0089] In step S5, 1 part of monomer two is added to the mixture, and the small molecule compound containing three [MaMbN2X2O2] structures in step S4 is connected to each other to obtain a large molecule polymer with a structure of [MaMbN4X2].

[0090] I. Preparation method

[0091] Example 1

[0092] Synthesis of homometallic bimetallic atom: 2 parts of methanol solution of Co(NO3)2·6H2O is mixed with 2 parts of methanol solution containing 2-hydroxyisophthalaldehyde, and after the solution is uniformly mixed, 1 part of methanol solution containing 1,2,4,5-benzene tetramine is slowly added to the above uniform solution, and condensation reflux is performed. Orange crystals are found to precipitate, and then filtration, washing and drying are performed to obtain a homometallic bimetallic atom polymer Co-DP.

[0093] Example 2

[0094] Synthesis of heterometallic bimetallic atom: 2 parts of methanol solution of Co(NO3)2·6H2O is mixed with 4 parts of methanol solution containing 2-hydroxyisophthalaldehyde, and after the solution is uniformly mixed, 1 part of methanol solution containing 1,2,4,5-benzene tetramine is slowly added to the above uniform solution, and condensation reflux is performed. Orange crystals are found to precipitate, and then filtration, washing and drying are performed to obtain a small molecule compound Co-P'. The Co-P' is added to a methanol solution to form a uniform mixed solution, and under the protection of argon atmosphere, 2 parts of methanol solution of FeCl2·4H2O is slowly added dropwise. When the color of the mixture does not change, 1 part of methanol solution of 1,2,4,5-benzene tetramine is added. After a while, the obtained precipitate is filtered, washed and dried to obtain a heterometallic bimetallic atom polymer CoFe-DP.

[0095] Example 3

[0096] Synthesis of planar double-metal atom polymer catalyst material: according to the molar fraction, carbon nanotubes are dispersed in a methanol solution, 3 parts of a methanol solution of 2-hydroxyisophthalaldehyde is slowly added to the stirring carbon nanotube dispersion, then 3 parts of Co(NO3)2·6H2O is added to the above homogeneous solution, after a uniform dispersion is formed, 1 part of a methanol solution of 2,3,6,7,10,11-hexamino triphenyl is slowly added to the solution, then the obtained homogeneous solution is subjected to condensation reflux, followed by filtration, washing and drying, to obtain carbon nanotubes loaded with homometallic double-metal atom planar polymer Co-DP.

[0097] Example 4

[0098] Synthesis of linear double-metal atom polymer catalyst material: according to the molar fraction, carbon nanotubes are dispersed in a methanol solution, 2 parts of a methanol solution of 2-hydroxyisophthalaldehyde is slowly added to the stirring carbon nanotube dispersion, then 2 parts of Co(NO3)2·6H2O is added to the above homogeneous solution, after a uniform dispersion is formed, 1 part of a methanol solution of 1,2,4,5-benzene tetramine is slowly added to the solution, then the obtained homogeneous solution is subjected to condensation reflux for 3 hours, followed by filtration, washing and drying, to obtain carbon nanotubes loaded with homometallic double-metal atom linear polymer Co-DP, named as S-Co@CNT.

[0099] Example 5

[0100] Synthesis of linear double-metal atom polymer catalyst material: according to the molar fraction, carbon nanotubes are dispersed in a methanol solution, 2 parts of a methanol solution of 2-hydroxyisophthalaldehyde is slowly added to the stirring carbon nanotube dispersion, then 2 parts of Co(NO3)2·6H2O is added to the above homogeneous solution, after a uniform dispersion is formed, 1 part of a methanol solution of 1,2,4,5-benzene tetramine is slowly added to the solution, then the obtained homogeneous solution is subjected to condensation reflux for 3 hours, followed by filtration, washing and drying, to obtain carbon nanotubes loaded with homometallic double-metal atom linear polymer Co-DP, named as S-Co@CNT.

[0101] II. Analysis of test results of each example

[0102] (1) Transmission electron microscopy scanning is respectively performed on the S-Co@CNT catalyst obtained in Example 4 and the L-Co@CNT catalyst obtained in Example 5, to obtain Figure 1 , Figure 1 a is a transmission electron microscopy scanning diagram of S-Co@CNT, Figure 1 b is a transmission electron microscopy scanning diagram of L-Co@CNT, from Figure 1 a and Figure 1 b, it can be seen that the polymer and the carbon nanotubes are successfully compounded.

[0103] (2) Figure 2 The spherical aberration-corrected transmission electron microscopy (STEM) images of S-Co@CNT catalysts are shown in FIG. 2. Figure 2 From FIG. 2, it can be observed that pairs of metal atoms are observed, and no agglomeration of metal atoms is found, which proves the uniform distribution of the atoms.

[0104] (3) The oxygen reduction performance of S-Co@CNT catalyst obtained in Example 4, L-Co@CNT catalyst obtained in Example 5 and commercial Pt / C catalyst was tested using a rotating disk electrode. The specific testing method was as follows: the temperature was 25°C, the electrolyte used was oxygen-saturated 0.1 M KOH aqueous solution, the working electrode was a glassy carbon rotating disk electrode with an area of 0.19625 cm -2 , the rotation speed was 1600 rpm; the counter electrode was a carbon rod, and the reference electrode was a saturated Ag / AgCl electrode. The reference electrode potential was corrected by a reversible hydrogen electrode. 6 mg of catalyst was weighed, 970 μL of ethanol and 30 μL of 5% Nafion solution were added for ultrasonic dispersion to prepare a catalyst slurry, 20 μL of catalyst ink was dropped on the rotating disk electrode, and it was naturally air-dried. The scanning rate was 10 mV s -1 during the oxygen reduction test. The results of the rotating disk electrode test of the catalysts are shown in Figure 3 , Figure 4 and Table 1.

[0105] Table 1 Rotating disk electrode test results of catalysts in Examples 4-5 and commercial Pt / C catalyst

[0106]

[0107] From Table 1, it can be seen that by adjusting the distance between the two metal atoms, the catalytic activity is affected. The half-wave potential of the S-Co@CNT catalyst is 0.973 V, which is higher than that of the L-Co@CNT catalyst, 0.907 V, and both are higher than that of the commercial Pt / C catalyst, 0.875 V.

[0108] From Figure 3 , it can be seen that the half-wave potential and the limiting current density of the S-Co@CNT catalyst and the L-Co@CNT catalyst are both higher than those of the commercial Pt / C catalyst, and the half-wave potential and the limiting current density of the S-Co@CNT catalyst are the highest.

[0109] From Figure 4 , it can be seen that the selectivity of the S-Co@CNT catalyst and the L-Co@CNT catalyst is slightly lower than that of the commercial Pt / C catalyst, but the selectivity of the S-Co@CNT catalyst is higher than that of the L-Co@CNT catalyst, which indicates that the S-Co@CNT has higher four-electron selectivity.

[0110] The above not involved, apply to the prior art.

[0111] Although some specific embodiments of the present application have been described in detail by way of examples, it should be understood that the examples are for illustration only and should not limit the scope of the present application. Those skilled in the art can make various modifications or additions to the described specific embodiments or adopt similar ways to replace them without departing from the spirit of the present application or exceeding the scope of the appended claims. Those skilled in the art should understand that any modification, equivalent replacement, improvement, etc. made to the above embodiments in accordance with the technical essence of the present application should be included in the protection scope of the present application.

Claims

1. A metal diatomic polymer catalyst material, characterized in that: Using a matrix material as a support, a metal diatomic polymer catalyst with adjustable atomic spacing is loaded on the surface; the metal diatomic polymer catalyst is composed of a polymer obtained by reacting monomer one and monomer two, which is complexed with metal ions, wherein monomer one is an aromatic monomer containing hydroxyl and aldehyde groups, and monomer two is an aromatic tetraamine or hexamine monomer; The aromatic monomer containing hydroxyl and aldehyde groups is one of 2-hydroxyisophthalaldehyde, 1,8-dihydroxy-2,7-naphthalenedicarboxyl, and 1,9-dihydroxy-2,8-anthracitecaaldehyde. The aromatic tetraamine or hexamine monomer is one of 1,2,4,5-phenyltetramine, 2,3,6,7-tetraaminonaphthalene, anthracene-2,3,6,7-tetramine, 4,5,9,10-tetraaminopyrene, and 2,3,6,7,10,11-hexaminetriphenyl. The metal is one or more selected from Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sn, Ru, Rh, Pd, Ir, Pt, Ag, and Au; The matrix material is carbon nanotubes.

2. A metal diatomic polymer catalyst material according to claim 1, characterized in that, The preparation method of the metal diatomic polymer catalyst includes the following steps: S1. Mix the methanol solution of monomer one with the methanol solution of metal ions until homogeneous to obtain a mixed solution; S2. Slowly add the methanol solution of monomer two to the mixture obtained in step S1, and reflux until crystals precipitate. S3. Filter, wash and dry the crystals obtained in step S2 to obtain the homogeneous bimetallic atom polymer M-DP.

3. The metal-polymer catalyst material with adjustable atomic spacing according to claim 2, characterized in that: When the second monomer is a tetraamine monomer, the molar ratio of the first monomer, the second tetraamine monomer, and the metal ion is (1.8-2.2):1:(1.8-2.2); when the second monomer is a hexamine monomer, the molar ratio of the first monomer, the second hexamine monomer, and the metal ion is (2.8-3.2):1:(2.8-3.2).

4. A metal diatomic polymer catalyst material according to claim 1, characterized in that, The preparation method of the metal diatomic polymer catalyst includes the following steps: S1. Mix the methanol solution of monomer one with the methanol solution of metal Ma to obtain a mixed solution. S2. Slowly add the methanol solution of monomer two to the mixture obtained in step S1, reflux and condense until crystals precipitate. S3. Filter, wash and dry the crystal obtained in step S2 to obtain the atomic polymer Ma-P' of the complex metal Ma; S4. Disperse the Ma-P' obtained in step S3 in a methanol solution to form a Ma-P' methanol mixture. Slowly add a methanol solution of metal Mb to the Ma-P' methanol mixture, and react to form a mixture. S5. When the color of the mixture in step S4 remains unchanged, add a methanol solution of monomer II. After the reaction is complete, filter, wash and dry the resulting precipitate to obtain the heterobimetallic atom polymer MaMb-DP.

5. The metal diatomic polymer catalyst material according to claim 4, characterized in that: When the second monomer is a tetraamine monomer, the molar ratio of the first monomer in step S1, the second tetraamine monomer in step S2, and the second tetraamine monomer in step S5 is (3.8-4.2):1:1, and the molar ratio of the first monomer, metallic Ma, and metallic Mb is (3.8-4.2):(1.8-2.2):(1.8-2.2); when the second monomer is a hexamine monomer, the molar ratio of the first monomer in step S1, the second hexamine monomer in step S2, and the second hexamine monomer in step S5 is (5.8-6.2):1:1, and the molar ratio of the first monomer, metallic Ma, and metallic Mb is (5.8-6.2):(2.8-3.2):(2.8-3.2).

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