A nitrogen-tellurium co-doped carbon supported cobalt lanthanum gallium triatomic oxygen reduction catalyst, a preparation method and application thereof

Abstract

The application discloses a nitrogen-tellurium co-doped carbon supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst and a preparation method and application thereof. The catalyst is composed of a carbon carrier, doped nitrogen and tellurium atoms, and supported cobalt, lanthanum and gallium atoms. The doping ratio of the nitrogen and tellurium atoms in the carrier is 3.63-6.96 wt% and 2.11-3.83 wt% respectively, the loading amount of the cobalt atom is 0.86-1.05 wt%, the loading amount of the lanthanum atom is 0.38-0.47 wt%, and the loading amount of the gallium atom is 0.21-0.47 wt%. In the preparation method, the nitrogen-tellurium co-doped carbon carrier is used to realize full anchoring coordination of Co and La atoms through a hydrothermal reaction, and the freeze-drying can effectively avoid the collapse of the carbon skeleton of the catalyst. The catalyst obtained by the application exhibits good oxygen reduction activity in a solid-state zinc-air battery, and the peak power density is up to 1.68 mW cm ‑2 .

Description

Technical Field

[0001] This invention relates to the field of oxygen reduction catalyst technology, and more particularly to a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst. Background Technology

[0002] To reduce dependence on traditional fossil fuels, the scientific community is focusing on developing new green energy conversion devices with high energy density and low environmental impact, such as zinc-air batteries and proton exchange membrane fuel cells (PEMFCs). The applications of zinc-air batteries and PEMFCs have already covered cutting-edge fields such as new energy vehicles, aerospace engineering, and precision medical equipment. However, the slow oxygen reduction reaction kinetics at the cathode severely restricts the actual output performance of these batteries in production and daily life. Existing commercial platinum-based oxygen reduction catalysts are constrained by the scarcity of precious metals, creating a major obstacle to the commercialization of zinc-air batteries and PEMFCs. Therefore, developing highly active and stable non-precious metal oxygen reduction catalysts to replace platinum-based materials has become an urgent need to overcome the current technological bottleneck.

[0003] In the current technology, patent (ZL 2024 1 1027436.X) describes a nitrogen-fluorine co-doped carbon-supported zinc-molybdenum diatomic oxygen reduction catalyst prepared sequentially through physical grinding, mixing and impregnation, vacuum drying, and secondary pyrolysis. The catalyst consists of a carbon substrate, nitrogen and fluorine non-metallic atoms, and zinc and molybdenum metal atoms. This catalyst optimizes the single-atom Mo-N composition by introducing fluorine atoms. x The d-band central electronic structure of the site improves the intrinsic activity of the catalyst; however, due to the difficulty of fluorine atoms breaking the Mo-N group... x The symmetrical charge distribution around the site, and the fact that Mo atoms tend to agglomerate to form low-activity Mo2C nanoparticles during pyrolysis, especially the poor hydrophilicity of the surface of the nitrogen-fluorine co-doped carbon-supported zinc-molybdenum diatomic catalyst, result in the oxygen reduction catalytic activity and kinetic reaction rate remaining at a low level.

[0004] Therefore, it is imperative to optimize the composition of catalysts from the perspectives of avoiding the aggregation of active metal atoms, effectively breaking the symmetrical charge distribution, and improving the hydrophilicity of the catalyst surface, so as to develop a non-precious metal oxygen reduction catalyst with good catalytic performance. Summary of the Invention

[0005] The purpose of this invention is to provide a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst to overcome the shortcomings of existing technologies. This catalyst introduces metal elements La and Ga atoms and non-metal elements Te atoms into the Co-NC catalyst, effectively breaking down the Co-N structure through the La and Ga metal atoms. xThe symmetrical charge distribution around the sites utilizes the Co, La, and Ga orbital coupling effect to modulate the d-band central electronic structure of cobalt atoms, thereby effectively reducing the adsorption strength of cobalt atoms on oxygen reduction reaction intermediates and promoting the smooth progress of subsequent elementary reactions, thus improving the intrinsic activity of the catalyst. Introducing tellurium doping enhances the hydrophilicity of the catalyst surface, improving the accessibility of active sites in the electrolyte and increasing the utilization rate of the Co-La-Ga three-atom sites. In the preparation method, hydrothermal reaction is used to achieve sufficient anchoring and coordination of Co and La atoms on the nitrogen-tellurium co-doped carbon support; freeze-drying effectively prevents the collapse of the catalyst's carbon framework. The catalyst obtained in this invention exhibits excellent oxygen reduction activity in solid-state zinc-air batteries, with a peak power density as high as 1.68 mW cm⁻¹. -2 .

[0006] The technical solution of this invention is as follows:

[0007] A nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst, the catalyst comprising a carbon support, doped nitrogen and tellurium atoms, and supported cobalt, lanthanum, and gallium atoms;

[0008] The doping ratios of nitrogen and tellurium atoms in the support are 3.63–6.96 wt% and 2.11–3.83 wt%, respectively; the loading of cobalt atoms is 0.86–1.05 wt%; the loading of lanthanum atoms is 0.38–0.47 wt%; and the loading of gallium atoms is 0.21–0.47 wt%. Furthermore, because the catalyst comes into contact with air, a small amount of oxygen molecules are adsorbed on its surface.

[0009] The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst includes the following steps:

[0010] 1) Nitrogen source, tellurium source and biomass powder are added together to the first solvent, and the precursor powder is obtained by magnetic stirring, vacuum drying and grinding.

[0011] The first solvent contains 0.1-1 g of biomass powder and 0.01-0.05 mol of nitrogen source per 100 mL of solvent; the molar ratio of nitrogen source to tellurium source is 1:0.1-0.5.

[0012] 2) The precursor powder was heated to 800~1100 ℃ under a nitrogen atmosphere and pyrolyzed for 1.2~3h to obtain nitrogen-tellurium co-doped carbon support;

[0013] 3) Nitrogen-tellurium co-doped carbon support, lanthanum salt, and cobalt salt containing complex ions are added to the second solvent, then transferred to a closed reactor, and subjected to hydrothermal reaction at 50-160 °C for 3-12 h. After vacuum drying, the resulting product is heated to 850-1000 °C in a hydrogen-argon mixed atmosphere and pyrolyzed for 1-3 h to finally obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0014] In this process, 0.5-1g of nitrogen-tellurium co-doped carbon support and 0.002-0.005 mol of lanthanum salt are added to every 100mL of the second solvent; the molar ratio of lanthanum salt to cobalt salt is 1:1-10.

[0015] 4) The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and gallium salt were magnetically stirred in a third solvent. After mixing, the mixture was freeze-dried. The dried product was then transferred to a tube furnace and heated to 870-940℃ under a nitrogen atmosphere for pyrolysis for 1.5-3 hours to finally obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC).

[0016] In this process, 0.02~1.25g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.001~0.988g of gallium salt were added to every 100 mL of the third solvent; the freeze-drying time was 23~76 h and the freeze-drying temperature was -42~-48 ℃.

[0017] Step 1) The nitrogen source comprises one or more of 2,6-diaminopurine, melamine, D-glucosamine, N-acetyl-L-cysteine, sodium 4-aminobenzoate and 6-bromopurine;

[0018] The tellurium source is one or more of sodium tellurite, tellurium dioxide, biphenyl tellurium, tellurium tetrachloride, and potassium tellurite.

[0019] The biomass powder is one or more of the following: dried goji berries, sunflower seed shells, dried carrots, chestnut shells, and peanut shell powder; the particle size of the biomass powder ranges from 0.01 to 0.1 micrometers.

[0020] The first solvent is one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone.

[0021] Step 1) The magnetic stirring speed is 260~600 r / min, and the magnetic stirring time is 4~20 h; the vacuum drying temperature is 65~85 ℃, and the vacuum drying time is 7~24 h; the grinding time is 16~50 min.

[0022] The heating rate in step 2) is 2~7℃ / min.

[0023] Step 3) The cobalt salt containing the complex ion includes one or more of potassium cobalt cyanide, potassium hexanitrocobaltate, sodium tetracarbonylcobaltate, and sodium percobaltate;

[0024] Lanthanum salts are one or more of the following: lanthanum oxalate hydrate, lanthanum hexaboride, lanthanum nitrate, lanthanum acetate hexahydrate, lanthanum sulfate hydrate, and lanthanum chloride hexahydrate;

[0025] The second solvent comprises one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone;

[0026] Step 3) The vacuum drying temperature is 45~100 ℃, and the vacuum drying time is 6~36 h;

[0027] Step 3) The heating rate to the pyrolysis temperature is 3~6 ℃ / min, and the volume ratio of hydrogen in the hydrogen-argon mixture is 1~10%.

[0028] Step 4) The gallium source comprises one or more of gallium acetylacetonate, gallium sulfate hydrate, gallium phthalocyanine chloride, gallium bromide, gallium nitride, and gallium iodide;

[0029] The third solvent comprises one or more of water, N,N-dimethylformamide, methanol, and ethanol.

[0030] In step 4), the freeze-drying time is 24~34 h and the freeze-drying temperature is -42~-46 ℃.

[0031] Step 4) The magnetic stirring speed is 85~170 r / min, and the magnetic stirring time is 1~7 h.

[0032] Step 4) The heating rate to the pyrolysis temperature is 3~14 °C / min.

[0033] The present invention also provides a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared by the aforementioned preparation method.

[0034] The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst is used as a cathode in a solid-state zinc-air battery.

[0035] The essential features of this invention are:

[0036] This invention optimizes the active metal center of the catalyst from easily agglomerated Mo to less agglomerated Co. Furthermore, since lanthanum and gallium are both metal atoms, their orbital configurations and electronic properties differ significantly from those of nitrogen atoms; therefore, introducing lanthanum and gallium doping can more effectively break the Co-N agglomeration. xSymmetrical charge distribution near the sites. The coupling effect of Co 3d orbitals with La 4f and Ga 4p orbitals is utilized to adjust the central electronic structure of the d-band of cobalt atoms, thereby appropriately reducing the adsorption strength of cobalt atoms for oxygen reduction reaction intermediates and promoting the smooth progress of subsequent elementary reactions, thus improving the intrinsic activity of the catalyst. On the other hand, this invention introduces tellurium doping to enhance the hydrophilicity of the catalyst surface, thereby improving the accessibility of active sites on the catalyst surface in the electrolyte, increasing the utilization rate of the Co-La-Ga triatomic sites, and simultaneously promoting sufficient contact and activation of oxygen at the Co-La-Ga triatomic sites, ultimately accelerating the oxygen reduction reaction kinetics.

[0037] The beneficial effects of this invention include:

[0038] 1) This invention uses one or more of the following as carbon carriers: inexpensive, readily available, and abundant dried goji berries, sunflower seed shells, dried carrots, chestnut shells, and peanut shells. This helps to reduce the development cost of oxygen reduction catalysts and also facilitates the utilization of high added value of agricultural and sideline products.

[0039] 2) In Co-NC catalysts, the symmetrically distributed charge of single-atom Co-Nx sites leads to excessive adsorption of oxygen reduction reaction intermediates, inhibiting the smooth progress of subsequent elementary reactions and resulting in low intrinsic activity of the Co-NC catalyst. To address this issue, this invention introduces lanthanum and gallium atoms into Co-NC to construct Co-La-Ga triatomic sites. Since La and Ga are both metal atoms, their orbital configurations and electronic properties differ significantly from those of nitrogen atoms, thus more effectively breaking down the Co-Nx structure. x Symmetrical charge distribution near the site. The coupling effect of Co 3d orbitals with La 4f and Ga 4p orbitals is utilized to modulate the central electronic structure of the d-band of cobalt atoms, thereby appropriately reducing the adsorption strength of cobalt atoms for oxygen reduction reaction intermediates, promoting the smooth progress of subsequent elementary reactions, and thus improving the intrinsic activity of the catalyst. For example... Figure 3 As shown, the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared in Example 1 exhibits a half-wave potential as high as 0.874 V in alkaline electrolyte, which is significantly higher than that of the nitrogen-tellurium co-doped carbon-supported cobalt single-atom catalyst (Co-TeNC) prepared in Comparative Example 3. E 1 / 2 =0.855 V) and the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC, Comparative Example 1) prepared by comparison example 1 E 1 / 2 =0.843 V). This demonstrates that the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst exhibits higher oxygen reduction catalytic activity.

[0040] 3) The poor surface hydrophilicity of Co-NC catalysts reduces the accessibility of active sites in the electrolyte, resulting in low utilization of active sites and thus affecting the oxygen reduction reaction rate. To address this issue, this invention introduces tellurium doping to enhance the hydrophilicity of the catalyst surface, thereby improving the accessibility of active sites in the electrolyte, increasing the utilization rate of Co-La-Ga triatomic sites, and simultaneously promoting sufficient contact and activation of Co-La-Ga triatomic sites with oxygen, ultimately accelerating the oxygen reduction reaction kinetics. Figure 4 As shown, the contact angle of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared in Example 1 is 28.233°, indicating that its surface has strong hydrophilicity. In contrast, the contact angle of the nitrogen-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-NC) prepared in Comparative Example 2 is as high as 136.052°, and the contact angle of the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1 is as high as 128.649°, both exhibiting extremely strong hydrophobicity. This demonstrates that the introduction of tellurium can effectively enhance the hydrophilicity of the catalyst surface. Thanks to the construction of the hydrophilic surface, such as... Figure 5 As shown, the kinetic current density (7.534 mA cm⁻¹) of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared in Example 1 is shown. -2 It was also significantly higher than that of control sample 2 (5.378 mA cm⁻¹). -2 ) and Comparative Example 1 (4.974 mA cm) -2 This indicates that the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst prepared in Example 1 has better site utilization and oxygen reduction kinetics.

[0041] 4) The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst prepared in this invention possesses highly active Co-La-Ga triatomic sites with low adsorption strength and a highly hydrophilic surface structure, thus exhibiting good oxygen reduction activity as a catalyst in solid-state zinc-air batteries. For example... Figure 6 As shown, the solid-state zinc-air battery assembled using the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst (Co,La,Ga-TeNC) prepared in Example 1 achieves a peak power density of 1.68 mW cm⁻¹. -2 In contrast, the solid-state zinc-air battery assembled using the nitrogen-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-NC) prepared in Comparative Example 1 had a peak power density of only 1.05 mW cm⁻¹. -2 Therefore, it can be seen that the solid-state zinc-air battery assembled with a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst has better performance. Attached Figure Description

[0042] Figure 1 The X-ray diffraction pattern of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1 is shown.

[0043] Figure 2 This is a transmission electron microscope image of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1.

[0044] Figure 3 The half-wave potentials are those of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1, the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1, and the nitrogen-tellurium co-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-TeNC) prepared in Comparative Example 3.

[0045] Figure 4 The contact angle test results are for the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1, the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1, and the nitrogen-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-NC) prepared in Comparative Example 2.

[0046] Figure 5 The kinetic current density is shown for the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1, the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1, and the nitrogen-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-NC) prepared in Comparative Example 2.

[0047] Figure 6 The graph shows the test performance of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1 and the nitrogen-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-NC) of Comparative Example 1 in a solid-state zinc-air battery. Detailed Implementation

[0048] This invention provides a method for preparing a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst, comprising the following steps:

[0049] 1) Nitrogen source, tellurium source and biomass powder are added together to 100 mL of the first solvent, and the precursor powder is obtained after uniform magnetic stirring, vacuum drying and thorough grinding in an agate mortar.

[0050] The amount of biomass powder added is 0.1~1g, and the amount of nitrogen source added is 0.01~0.05 mol; the molar ratio of nitrogen source to tellurium source is 1:0.1~0.5.

[0051] 2) The precursor powder was heated to 500~1400 ℃ under a nitrogen atmosphere and pyrolyzed for 1~8.5 h to obtain nitrogen-tellurium co-doped carbon support;

[0052] 3) The nitrogen-tellurium co-doped carbon support, lanthanum salt, and cobalt salt containing the complex ion were added to 100 mL of the second solvent, and then transferred to a closed reactor. After hydrothermal reaction and vacuum drying, the resulting product was heated to 500~1350 °C in a hydrogen-argon mixed atmosphere and pyrolyzed for 0.5~6.5 h to finally obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0053] The amount of nitrogen-tellurium co-doped carbon support added is 0.5~1g; the amount of lanthanum salt added is 0.002~0.005 molmol; the molar ratio of lanthanum salt to cobalt salt is 1:1~10; the hydrothermal reaction time is 1~48 h, and the reaction temperature is 40~300℃.

[0054] 4) The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and gallium salt were magnetically stirred in 100 mL of a third solvent. After mixing, the mixture was freeze-dried. The dried product was then transferred to a tube furnace and heated to 820~1300 ℃ under a nitrogen atmosphere for pyrolysis for 0.5~3.2 h to finally obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC).

[0055] The amount of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material added was 0.02~1.25 g, and the amount of gallium salt added was 0.001~0.988 g; the freeze-drying time was 23~76 h, and the freeze-drying temperature was -42~-48 ℃;

[0056] In this invention, the nitrogen source in step 1) preferably comprises one or more of 2,6-diaminopurine, melamine, D-glucosamine, N-acetyl-L-cysteine, sodium 4-aminobenzoate, and 6-bromopurine; the tellurium source preferably comprises one or more of sodium tellurite, tellurium dioxide, biphenyl tellurium, tellurium tetrachloride, and potassium tellurite; the biomass powder preferably comprises one or more of dried wolfberry, sunflower seed shell, dried carrot, chestnut shell, and peanut shell powder; the biomass powder particle size range is preferably 0.01~0.1 micrometers; the first solvent preferably comprises one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone.

[0057] In this invention, the magnetic stirring speed in step 1) is preferably 20~700 r / min, more preferably 80~500 r / min, and even more preferably 200~300 r / min; the magnetic stirring duration is preferably 3~24 h, more preferably 6~18 h, and even more preferably 12 h; the vacuum drying temperature is preferably 40~90 ℃, more preferably 60~80 ℃, and even more preferably 70 ℃; the vacuum drying time is preferably 3~24 h, more preferably 5~18 h, and even more preferably 12 h; and the grinding time is preferably 10~60 min, more preferably 15~45 min, and even more preferably 30 min.

[0058] In this invention, the heating rate of step 2) to the pyrolysis temperature is preferably 1~35 ℃ / min, more preferably 3~10 ℃ / min, and even more preferably 4~7 ℃ / min.

[0059] In this invention, the cobalt salt containing the complex ion in step 3) comprises one or more of potassium cobalt cyanide, potassium hexanitrocobaltate, sodium tetracarbonylcobaltate, and sodium percobaltate; the lanthanum salt comprises one or more of lanthanum oxalate hydrate, lanthanum hexaboride, lanthanum nitrate, lanthanum acetate hexahydrate, lanthanum sulfate hydrate, and lanthanum chloride hexahydrate; the second solvent comprises one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone.

[0060] In this invention, the vacuum drying temperature in step 3) is preferably 45~100 ℃, more preferably 60~90 ℃, and even more preferably 70~80 ℃; the vacuum drying time is preferably 6~36 h, more preferably 8~24 h, and even more preferably 11~13 h.

[0061] In this invention, the heating rate to the pyrolysis temperature in step 3) is preferably 1~28 ℃ / min, more preferably 3~10 ℃ / min, and even more preferably 5~6 ℃ / min; the volume ratio of hydrogen in the hydrogen-argon mixture is preferably 1~10%, more preferably 3~6%, and even more preferably 5%.

[0062] In this invention, the gallium source in step 4) preferably includes one or more of gallium acetylacetonate, gallium sulfate hydrate, gallium chlorophthalocyanine, gallium bromide, gallium nitride, and gallium iodide; the third solvent preferably includes one or more of water, N,N-dimethylformamide, methanol, and ethanol.

[0063] In this invention, the magnetic stirring speed in step 4) is preferably 45~640 r / min, more preferably 60~460 r / min, and even more preferably 100~180 r / min; the magnetic stirring duration is preferably 1~7 h, more preferably 2~6 h, and even more preferably 3~4 h.

[0064] In this invention, the heating rate of step 4) to the pyrolysis temperature is preferably 3~14 ℃ / min, more preferably 4~11 ℃ / min, and even more preferably 5~7 ℃ / min.

[0065] The present invention also provides a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared by the aforementioned preparation method.

[0066] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0067] Example 1:

[0068] 0.02 mol of 2,6-diaminopurine, 0.004 mol of sodium tellurite, and 0.27 g of sunflower seed shell powder (particle size range 0.05~0.08 μm) were added to 100 mL of water and magnetically stirred at 260 r / min for 12 h to ensure uniform mixing. The mixture was then vacuum dried at 70 °C for 12 h to obtain the final product. The final product was then ground in an agate mortar for 30 min to obtain the precursor powder.

[0069] The precursor powder was placed in a tube furnace under an argon atmosphere and heated to 900°C at a heating rate of 5°C / min. The mixture was then pyrolyzed at 900°C for 2 hours. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon support.

[0070] 0.77 g of nitrogen-tellurium co-doped carbon support, 0.004 mol of lanthanum nitrate, and 0.008 mol of potassium cobalt cyanide were added to 100 mL of water. The solution was then transferred to a sealed reactor and subjected to a hydrothermal reaction at 130 °C for 12 h. The reaction product was then vacuum dried at 70 °C for 12 h. Finally, the dried product was placed in a tube furnace under a hydrogen-argon mixed atmosphere (hydrogen volume percentage 5%) and heated to 910 °C at a heating rate of 6 °C / min. The product was then pyrolyzed at 910 °C for 2.5 h. After pyrolysis, the product was cooled to room temperature to obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0071] 0.15 g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.06 g of gallium nitride were added to 100 mL of methanol and magnetically stirred at 120 r / min for 3.7 h to ensure uniform mixing. The mixture was then freeze-dried at -46 ℃ for 24 h to obtain the dried product. Finally, the dried product was placed in a tube furnace under a nitrogen atmosphere and heated to 920 ℃ at a heating rate of 6 ℃ / min. Pyrolysis was continued at 920 ℃ for 1.7 h. After pyrolysis, the mixture was cooled to room temperature to obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC). The loading amounts of cobalt, lanthanum, and gallium atoms were 0.92 wt%, 0.47 wt%, and 0.24 wt%, respectively, and the doping ratios of nitrogen and tellurium atoms in the support were 4.72 wt% and 2.11 wt%, respectively. (See Table 1, obtained from X-ray photoelectron spectroscopy. The test methods for the following examples are the same). In addition, since the catalyst comes into contact with air, a small amount of oxygen molecules are adsorbed on its surface (the same applies to the following examples).

[0072] Example 2:

[0073] 0.03 mol melamine, 0.012 mol tellurium tetrachloride, and 0.32 g dried wolfberry powder (particle size range 0.06~0.07 μm) were added to 100 mL methanol and magnetically stirred at 280 r / min for 15 h to ensure uniform mixing. The mixture was then vacuum dried at 80 °C for 15 h to obtain the final product. The final product was then ground in an agate mortar for 40 min to obtain the precursor powder.

[0074] The precursor powder was placed in a tube furnace under a nitrogen atmosphere and heated to 950°C at a heating rate of 7°C / min. The mixture was then pyrolyzed at 950°C for 2.5 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon support.

[0075] 0.57 g of nitrogen-tellurium co-doped carbon support, 0.003 mol of lanthanum acetate hexahydrate, and 0.003 mol of potassium hexanitroscobaltate containing the complex ion were added to 100 mL of N,N-dimethylformamide. The solution was then transferred to a sealed reactor and subjected to a hydrothermal reaction at 70 °C for 6 h. The reaction product was then vacuum dried at 80 °C for 8 h. Finally, the dried product was placed in a tube furnace under a hydrogen-argon mixed atmosphere (hydrogen volume percentage 6%) and heated to 850 °C at a heating rate of 4 °C / min. The product was then pyrolyzed at 850 °C for 3 h. After pyrolysis, the product was cooled to room temperature to obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0076] 0.07 g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.005 g of gallium bromide were added to 100 mL of water and magnetically stirred at 150 r / min for 3.5 h to ensure homogeneous mixing. The mixture was then freeze-dried at -45 ℃ for 24 h to obtain the dried product. Finally, the dried product was placed in a tube furnace under a nitrogen atmosphere and heated to 910 ℃ at a heating rate of 5 ℃ / min. Pyrolysis was continued at 910 ℃ for 1.5 h, followed by cooling to room temperature to obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC). The loading amounts of cobalt, lanthanum, and gallium atoms were 0.86 wt%, 0.38 wt%, and 0.39 wt%, respectively, while the doping ratios of nitrogen and tellurium atoms in the support were 3.63 wt% and 2.78 wt%, respectively. Furthermore, due to the catalyst's contact with air, a small amount of oxygen molecules were adsorbed on its surface.

[0077] Example 3:

[0078] 0.03 mol of sodium 4-aminobenzoate, 0.006 mol of potassium tellurite, and 0.29 g of dried carrot powder (particle size range 0.04–0.06 μm) were added to 100 mL of N,N-dimethylformamide and magnetically stirred at 600 r / min for 4 h to ensure uniform mixing. The mixture was then vacuum dried at 65 °C for 7 h to obtain the final product. The final product was then ground in an agate mortar for 16 min to obtain the precursor powder.

[0079] The precursor powder was placed in a tube furnace under a nitrogen atmosphere and heated to 1100℃ at a heating rate of 3℃ / min. The mixture was then pyrolyzed at 1100℃ for 3 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon support.

[0080] 0.72 g of nitrogen-tellurium co-doped carbon support, 0.004 mol of lanthanum oxalate hydrate, and 0.005 mol of sodium tetracarbonyl cobaltate containing the complex ion were added to 100 mL of water. The solution was then transferred to a sealed reactor and subjected to a hydrothermal reaction at 160 °C for 10 h. The reaction product was then vacuum dried at 75 °C for 10 h. Finally, the dried product was placed in a tube furnace under a hydrogen-argon mixed atmosphere (hydrogen volume percentage 4%) and heated to 900 °C at a heating rate of 5 °C / min. The product was then pyrolyzed at 900 °C for 2 h. After pyrolysis, the product was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0081] 0.81 g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.126 g of gallium acetylacetonate were added to 100 mL of ethanol and magnetically stirred at 170 r / min for 3.8 h to ensure homogeneity. The mixture was then freeze-dried at -43 °C for 26 h to obtain the dried product. Finally, the dried product was placed in a tube furnace under a nitrogen atmosphere and heated to 940 °C at a heating rate of 5 °C / min. Pyrolysis was continued at 940 °C for 1.7 h, followed by cooling to room temperature to obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC). The loading amounts of cobalt, lanthanum, and gallium atoms were 1.05 wt%, 0.39 wt%, and 0.21 wt%, respectively, while the doping ratios of nitrogen and tellurium atoms in the support were 5.15 wt% and 3.83 wt%, respectively. Furthermore, due to the catalyst's contact with air, a small amount of oxygen molecules were adsorbed on its surface.

[0082] Example 4:

[0083] 0.05 mol of 6-bromopurine, 0.015 mol of biphenyl ditelluride, and 0.19 g of chestnut shell powder (particle size range 0.03–0.06 μm) were added to 100 mL of N-methylpyrrolidone and magnetically stirred at 350 r / min for 20 h to ensure uniform mixing. The mixture was then vacuum dried at 85 °C for 24 h to obtain the final product. The final product was then ground in an agate mortar for 50 min to obtain the precursor powder.

[0084] The precursor powder was placed in a tube furnace under a nitrogen atmosphere and heated to 800°C at a heating rate of 2°C / min. The mixture was then pyrolyzed at 800°C for 1.2 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon support.

[0085] 0.65 g of nitrogen-tellurium co-doped carbon support, 0.0046 mol of lanthanum hexaboride, and 0.0049 mol of sodium percobaltate containing complex ions were added to 100 mL of methanol. The solution was then transferred to a sealed reactor and subjected to a hydrothermal reaction at 50 °C for 3 h. The reaction product was then vacuum dried at 50 °C for 30 h. Finally, the dried product was placed in a tube furnace under a hydrogen-argon mixed atmosphere (hydrogen volume percentage 3%) and heated to 1000 °C at a heating rate of 3 °C / min. The product was then pyrolyzed at 1000 °C for 1 h. After pyrolysis, the product was cooled to room temperature to obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material.

[0086] 1.02 g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.072 g of gallium sulfate hydrate were added to 100 mL of N,N-dimethylformamide and magnetically stirred at 85 r / min for 5 h to ensure homogeneity. The mixture was then freeze-dried at -42 ℃ for 34 h to obtain the dried product. Finally, the dried product was placed in a tube furnace under a nitrogen atmosphere and heated to 870 ℃ at a heating rate of 3 ℃ / min. Pyrolysis was continued at 870 ℃ for 3 h, followed by cooling to room temperature to obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC). The loading amounts of cobalt, lanthanum, and gallium atoms were 0.94 wt%, 0.45 wt%, and 0.47 wt%, respectively, while the doping ratios of nitrogen and tellurium atoms in the support were 6.96 wt% and 3.17 wt%, respectively. Furthermore, due to contact with air, a small amount of oxygen molecules were adsorbed on the catalyst surface.

[0087] Table 1 shows the X-ray photoelectron spectroscopy results of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalysts (Co,La,Ga-TeNC) in Examples 1, 2, 3 and 4.

[0088]

[0089] Comparative Example 1:

[0090] 85 mg Ketjen black, 14 mg cobalt acetylacetonate, 50 mg zinc nitrate hexahydrate, 20 mg o-phenanthroline, and 500 mg melamine were dissolved in 10 mL of an ethanol / water mixture (ethanol to water volume ratio of 1:1). The mixture was then magnetically stirred at 220 r / min for 2 h to ensure homogeneity, followed by vacuum drying at 80 °C for 12 h to obtain the final mixture. The mixture was then ground in an agate mortar for 10 min to obtain the precursor powder.

[0091] The precursor powder was placed in a tube furnace filled with a hydrogen-argon mixture (hydrogen volume percentage 5%) and heated to 900°C at a heating rate of 5°C / min. The mixture was then pyrolyzed at 900°C for 2 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-NC).

[0092] Comparative Example 2:

[0093] 85 mg Ketjen black, 14 mg cobalt acetylacetonate, 0.06 g gallium nitride, 0.0006 mol lanthanum hexaboride, 50 mg zinc nitrate hexahydrate, 20 mg o-phenanthroline, and 500 mg melamine were dissolved in 10 mL of an ethanol / water mixture (ethanol to water volume ratio of 1:1). The mixture was then magnetically stirred at 220 r / min for 2 h to ensure homogeneity, followed by vacuum drying at 80 ℃ for 12 h to obtain the final mixture. The mixture was then ground in an agate mortar for 10 min to obtain the precursor powder.

[0094] The precursor powder was placed in a tube furnace filled with a hydrogen-argon mixture (hydrogen volume percentage 5%) and heated to 900°C at a heating rate of 5°C / min. The mixture was then pyrolyzed at 900°C for 2 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-NC).

[0095] Comparative Example 3:

[0096] 85 mg Ketjen black, 14 mg cobalt acetylacetonate, 0.006 mol potassium tellurite, 50 mg zinc nitrate hexahydrate, 20 mg o-phenanthroline, and 500 mg melamine were dissolved in 10 mL of an ethanol / water mixture (ethanol to water volume ratio of 1:1). The mixture was then magnetically stirred at 220 r / min for 2 h to ensure homogeneity, followed by vacuum drying at 80 ℃ for 12 h to obtain the final mixture. The mixture was then ground in an agate mortar for 10 min to obtain the precursor powder.

[0097] The precursor powder was placed in a tube furnace filled with a hydrogen-argon mixture (hydrogen volume percentage 5%) and heated to 900°C at a heating rate of 5°C / min. The mixture was then pyrolyzed at 900°C for 2 h. After pyrolysis, the mixture was cooled to room temperature to obtain a nitrogen-tellurium co-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-TeNC).

[0098] The X-ray diffraction pattern (test instrument model: Bruker D8) and transmission electron microscopy (test instrument model: JEOL2100) of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) prepared in Example 1 are shown below. Figure 1 and Figure 2 As shown. From Figure 1 It can be seen that in the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst of Example 1, only the characteristic peaks corresponding to graphite carbon are observed near 25° and 44°, and no characteristic peaks corresponding to metal-based nanoparticles are observed; while from Figure 2It can be seen that no obvious metal nanoparticles were observed in the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst of Example 1. The above characterization results indicate that cobalt, lanthanum, and gallium atoms did not migrate and aggregate during pyrolysis, and the metal active centers in the catalyst exist in a triatomic dispersed form.

[0099] The half-wave potentials of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1, the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1, and the nitrogen-tellurium co-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-TeNC) prepared in Comparative Example 3 were measured in 0.1 mol / L KOH solution using a three-electrode system and a CHI760e electrochemical workstation. The catalyst loading was 0.459 mg cm⁻¹ for all catalysts. -2 .like Figure 3 As shown, the Co,La,Ga-TeNC prepared in Example 1 has a half-wave potential as high as 0.874 V in alkaline electrolyte, which is much higher than that of the Co-TeNC prepared in Comparative Example 3. E 1 / 2 =0.855 V) and Co-NC prepared in Comparative Example 1 ( =0.855 V) E 1 / 2 =0.843 V). This demonstrates that the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst exhibits higher oxygen reduction catalytic activity. This is mainly because the Co 3d-La 4f-Ga 4p orbital coupling effect effectively modulates the central electronic structure of the d-band of cobalt atoms, thereby appropriately reducing the adsorption strength of cobalt atoms for oxygen reduction reaction intermediates, promoting the smooth progress of subsequent elementary reactions, and thus improving the intrinsic activity of the catalyst.

[0100] The contact angle test results of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) in Example 1, the nitrogen-doped carbon-supported cobalt single-atom catalyst (Co-NC) prepared in Comparative Example 1, and the nitrogen-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-NC) in Comparative Example 2 are as follows: Figure 4 As shown (test instrument model: SDC 350). From Figure 4It can be seen that the contact angle of the Co,La,Ga-TeNC prepared in Example 1 is 28.233°, indicating that its surface has strong hydrophilicity. In contrast, the contact angle of the Co,La,Ga-NC prepared in Comparative Example 2 is as high as 136.052°, and the contact angle of the Co-NC prepared in Comparative Example 1 is as high as 128.649°, both exhibiting extremely strong hydrophobicity. This shows that the introduction of tellurium can effectively enhance the hydrophilicity of the catalyst surface. Thanks to the construction of the hydrophilic surface, the accessibility of the active sites on the catalyst surface in Example 1 in the electrolyte is effectively improved, the utilization rate of the Co-La-Ga three-atom sites is increased, and the sites are promoted to have sufficient contact and activation with oxygen, ultimately accelerating the oxygen reduction reaction kinetics. Furthermore, in a 0.1 mol / L KOH solution, the kinetic current density was measured using a three-electrode system and a CHI760e electrochemical workstation, and the results are as follows... Figure 5 As shown, the kinetic current density of the Co,La,Ga-TeNC prepared in Example 1 is 7.534 mA cm⁻¹. -2 It was also significantly higher than that of control sample 2 (5.378 mA cm⁻¹). -2 ) and Comparative Example 1 (4.974 mA cm) -2 This indicates that the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst prepared in Example 1 has better site utilization and oxygen reduction kinetics.

[0101] Solid-state zinc-air batteries were assembled using the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst (Co,La,Ga-TeNC) of Example 1 and the nitrogen-doped carbon-supported cobalt single-atom oxygen reduction catalyst (Co-NC) of Comparative Example 1 as cathode catalysts, respectively. The cathode catalyst loading was 1 mg / cm³. -2 The anode of the battery was a zinc plate (0.1 mm thick), and the solid electrolyte was a polyvinyl alcohol gel film (3 mm thick). The performance of the zinc-air battery was tested using the linear sweep voltammetry function of the Chenhua CHI760e electrochemical workstation. The performance graphs of Co,La,Ga-TeNC from Example 1 and Co-NC from Comparative Example 1 in the solid zinc-air battery are shown below. Figure 6 As shown. From Figure 6 It can be seen that the solid zinc-air battery assembled with the catalyst of Example 1 has a peak power density as high as 1.68 mW cm⁻¹. -2 The efficiency was significantly higher than that of the solid zinc-air battery assembled with the catalyst in Comparative Example 1 (1.05 mW cm⁻¹). -2 This indicates that the construction of Co-La-Ga triatomic sites and the doping of tellurium atoms in the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst effectively improved the oxygen reduction catalytic performance, thereby improving the actual output performance of the solid-state zinc-air battery.

[0102] This invention relates to a nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst. Using readily available and inexpensive biomass as the carbon support, it effectively reduces catalyst development costs. By introducing lanthanum and gallium to construct Co-La-Ga triatomic sites, the coupling effect of Co 3d orbitals with La 4f and Ga 4p orbitals is utilized to regulate the d-band central electronic structure of cobalt atoms, thereby appropriately reducing the adsorption strength of cobalt atoms for oxygen reduction reaction intermediates and promoting the smooth progress of subsequent elementary reactions. Simultaneously, non-metallic tellurium doping enhances the hydrophilicity of the catalyst surface, improves the accessibility of active sites in the electrolyte, promotes sufficient contact and activation of the catalyst with oxygen, and ultimately accelerates the oxygen reduction reaction kinetics. The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst possesses highly intrinsically active triatomic Co-La-Ga sites and a highly hydrophilic surface, exhibiting excellent oxygen reduction activity in solid-state zinc-air batteries. It solves the problems of excessively strong adsorption strength for intermediates and poor surface hydrophilicity that limit the oxygen reduction activity of current oxygen reduction catalysts.

[0103] Matters not covered in this invention are common knowledge.

Claims

1. A nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst, characterized in that, The catalyst consists of a carbon support, doped nitrogen and tellurium atoms, and supported cobalt, lanthanum, and gallium atoms. The doping ratios of nitrogen and tellurium atoms in the support are 3.63~6.96 wt% and 2.11~3.83 wt%, respectively; the loading of cobalt atoms is 0.86~1.05 wt%; the loading of lanthanum atoms is 0.38~0.47 wt%; and the loading of gallium atoms is 0.21~0.47 wt%.

2. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 1, characterized in that, It includes the following steps: 1) Nitrogen source, tellurium source and biomass powder are added together to the first solvent, and the precursor powder is obtained by magnetic stirring, vacuum drying and grinding. The first solvent contains 0.1-1 g of biomass powder and 0.01-0.05 mol of nitrogen source per 100 mL of solvent; the molar ratio of nitrogen source to tellurium source is 1:0.1-0.

5. The nitrogen source is one or more of 2,6-diaminopurine, melamine, D-glucosamine, N-acetyl-L-cysteine, sodium 4-aminobenzoate, and 6-bromopurine. The tellurium source is one or more of sodium tellurite, tellurium dioxide, biphenyl tellurium, tellurium tetrachloride, and potassium tellurite. The biomass powder is one or more of the following: dried goji berries, sunflower seed shells, dried carrots, chestnut shells, and peanut shell powder. The first solvent is one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone; 2) The precursor powder was heated to 800~1100 ℃ under a nitrogen atmosphere and pyrolyzed for 1.2~3h to obtain nitrogen-tellurium co-doped carbon support; 3) Nitrogen-tellurium co-doped carbon support, lanthanum salt, and cobalt salt containing complex ions are added to a second solvent, then transferred to a sealed reactor, and subjected to hydrothermal reaction at 50-160 °C for 3-12 h. After vacuum drying, the resulting product is heated to 850-1000 °C under a hydrogen-argon mixed atmosphere and pyrolyzed for 1-3 h to obtain nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material. In this process, 0.5-1 g of nitrogen-tellurium co-doped carbon support and 0.002-0.005 mol of lanthanum salt are added to every 100 mL of the second solvent; the molar ratio of lanthanum salt to cobalt salt is 1:1-10. The cobalt salt containing the complex ion is one or more of potassium cobalt cyanide, potassium hexanitrocobaltate, sodium tetracarbonylcobaltate, and sodium percobaltate; Lanthanum salts are one or more of the following: lanthanum oxalate hydrate, lanthanum hexaboride, lanthanum nitrate, lanthanum acetate hexahydrate, lanthanum sulfate hydrate, and lanthanum chloride hexahydrate; The second solvent is one or more of water, N,N-dimethylformamide, ammonia, methanol, acetonitrile, anisole, and N-methylpyrrolidone; 4) The nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and gallium salt were magnetically stirred in a third solvent. After mixing, the mixture was freeze-dried. The dried product was then transferred to a tube furnace and heated to 870-940℃ under a nitrogen atmosphere for pyrolysis for 1.5-3 hours to obtain the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst. In this process, 0.02~1.25g of nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum diatomic material and 0.001~0.988g of gallium salt are added to every 100 mL of the third solvent. The gallium source is one or more of gallium acetylacetonate, gallium sulfate hydrate, gallium phthalocyanine chloride, gallium bromide, gallium nitride, and gallium iodide; The third solvent is one or more of water, N,N-dimethylformamide, methanol, and ethanol.

3. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 2, characterized in that, Step 1) The particle size range of the biomass powder is 0.01~0.1 micrometers.

4. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 2, characterized in that, In step 1), the magnetic stirring speed is 260~600 r / min, the magnetic stirring time is 4~20 h; the vacuum drying temperature is 65~85 ℃, the vacuum drying time is 7~24 h; and the grinding time is 16~50 min.

5. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 2, characterized in that, The heating rate in step 2) is 2~7℃ / min.

6. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 2, characterized in that, Step 3) The vacuum drying temperature is 45~100 ℃, and the vacuum drying time is 6~36 h; Step 3) The heating rate to the pyrolysis temperature is 3~6 ℃ / min, and the volume ratio of hydrogen in the hydrogen-argon mixture is 1~10%.

7. The preparation method of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium three-atom oxygen reduction catalyst as described in claim 2, characterized in that, In step 4), the freeze-drying time is 24~34 h, and the freeze-drying temperature is -42~-46 ℃; Step 4) The magnetic stirring speed is 85~170 r / min, and the magnetic stirring time is 1~7 h; The heating rate to the pyrolysis temperature is 3~14 ℃ / min.

8. The application of the nitrogen-tellurium co-doped carbon-supported cobalt-lanthanum-gallium triatomic oxygen reduction catalyst as described in claim 1, characterized in that, Used as a cathode in solid-state zinc-air batteries.

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