Phosphate-based material with nanoporous structure, its manufacturing method and use

Abstract

Phosphate-based material with nanoporous structure, its manufacturing method and use. The chemical formula of ferromanganese phosphate is Mn 1-x Fe x PO4, 0.01≦x≦0.99, particle size is 50nm or less, and it has a porous structure. The chemical formula is Mn 1-a-b Fe a M b PO4, wherein M is one or a combination of five or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium, and 0.01≦a≦0.98, 10 -4 ≦b≦10 -2 The particle size is 50 nm or less, and the material also has a porous structure. The material can be used to prepare manganese iron phosphate-based battery cathode materials, and the specific capacity, multiplication factor, and cyclability of the resulting cathode materials are improved.

Description

[Technical Field]

[0001] The present invention relates to a phosphate-based material having a nanoporous structure, a method for producing the same, and uses thereof. [Background technology]

[0002] Over the past decade, nanomaterials and porous materials, functional materials with unique structures, have been attracting the attention of scientific researchers for their unique roles and value in many application fields, including photocatalysis, solar cells, electromagnetism, and optics. Ferromanganese phosphate materials are extremely important nonmetallic inorganic materials, such as bonderite, which provides rust and corrosion protection for steel products, and can also be used as ion exchangers, sensors, adsorbents, and magnetic materials. Ferromanganese phosphate is also an important precursor for manganese iron phosphate cathode materials in lithium-ion batteries. In ferromanganese phosphate materials, manganese and iron are uniformly mixed at the atomic level. When used to manufacture manganese iron phosphate cathode materials, the manganese iron metal element is distributed atomically uniformly in the cathode material, contributing to improved power performance and cycle stability of manganese iron phosphate lithium-ion batteries and reduced voltage drop and manganese leaching.

[0003] Currently, there are few reports in the literature on the preparation of ferromanganese phosphate, and even fewer on nano-porous ferromanganese phosphate. Chinese Patent CN111908442A discloses ferromanganese phosphate and its preparation method, which involves reacting manganese dioxide, ferrous oxalate, and phosphoric acid in the presence of a reducing agent (Mn 1-x Fe x ) a PO4·H2O crystals were obtained, and then filtered, washed, and sintered at high temperature to obtain amorphous (Mn 1-x Fe x ) aPO4 powder is obtained, and a reducing agent needs to be introduced during the production process, and heating is required during the reaction process. The particles of the obtained ferromanganese phosphate material are large in size, at the micron level, and the particles are dense and have no pore structure.

[0004] There are some documents in the prior art relating to the production of manganese phosphate, and the methods used include oxidation precipitation, reduction precipitation, and hydrothermal methods. However, the manganese phosphate particles produced by these methods are at the macron level, the particle size is too large, and the product solution contains a large amount of metal ions, resulting in a low purity. Furthermore, when producing ferromanganese phosphate using a manganese phosphate production method, it is not always possible to obtain pure ferromanganese phosphate, but it is possible to obtain a mixture of manganese phosphate and iron phosphate. Summary of the Invention

[0005] In response to the shortcomings and deficiencies of the prior art, the present invention provides a phosphate-based material with a nanoporous structure, which has small particles at the nano-level and exhibits a porous structure, and when used as a precursor for a manganese iron phosphate-based battery cathode material, can improve the specific capacity of the cathode material and the battery's power rating and cycle performance.

[0006] The present invention further provides a method for producing a phosphate-based material with a nanoporous structure, which does not require the use of a reducing agent and a soluble manganese salt, has mild reaction conditions, and can produce a high-purity phosphate-based material.

[0007] To achieve the above objectives, the technical solutions adopted in the present invention are as follows:

[0008] Ferromanganese phosphate, the chemical formula of which is Mn 1-x Fe x PO4, where 0.01≦x≦0.99, and the ferromanganese phosphate has a particle size of 50 nm or less and a porous structure.

[0009] In some embodiments, the particle size of the ferromanganese phosphate is 40 nm or less, more preferably 5 to 40 nm, and even more preferably 10 to 30 nm.

[0010] In some embodiments, the ferromanganese phosphate has a pore size of 2 to 10 nm, and preferably has a pore size of 3 to 5 nm.

[0011] In some embodiments, the specific surface area of ​​the ferromanganese phosphate is 10 to 30 m 2 / g, and preferably, the specific surface area of ​​the ferromanganese phosphate is 12 to 18 m 2 / g.

[0012] In some embodiments, 0.1≦x≦0.9, preferably 0.2≦x≦0.5, and more preferably 0.3≦x≦0.4.

[0013] In some embodiments, the ferromanganese phosphate is in the monoclinic crystal form.

[0014] The present invention further provides a phosphate-based material, the chemical formula of which is Mn 1-a-b Fe a M b PO4, M is one or a combination of one or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium, and 0.01≦a≦0.98, 10 -4 ≦b≦10 -2 The phosphate-based material has a particle size of 50 nm or less and a porous structure.

[0015] In some embodiments, the particle size of the phosphate-based material is 40 nm or less, more preferably 5 to 40 nm, and even more preferably 10 to 30 nm.

[0016] In some embodiments, the pore size of the phosphate-based material is 2 to 10 nm, and preferably, the pore size of the phosphate-based material is 3 to 5 nm.

[0017] In some embodiments, the specific surface area of ​​the phosphate-based material is 10 to 30 m 2 / g, and preferably, the specific surface area of ​​the ferromanganese phosphate is 12 to 18 m 2 / g.

[0018] In some embodiments, 0.2≦a≦0.5, 10 -3 ≦b≦10 -2 is.

[0019] In some embodiments, the phosphate-based material is in the monoclinic crystalline form.

[0020] In some embodiments, the M is cobalt, or the M is magnesium and boron, or the M is molybdenum, niobium and boron, or the M is cobalt, vanadium, nickel and boron, or the M is magnesium, or the M is vanadium and titanium. The phosphate-based material is a conventional doped ferromanganese phosphate material.

[0021] In some embodiments, the chemical formula of the phosphate-based material is Mn 1-a-b Fe a Co b PO4, or Mn 1-a-b Fe a Mg b1 B b2 PO4, b1+b2=b, or Mn 1-a-b Fe a Mo b1Nb b2 B b3 PO4, and b1+b2+b3=b and or Mn 1-a-b Fe a Co b1 V b2 Ni b3 B b4 PO4, b1+b2+b3+b4=b, or Mn 1-a-b Fe a Mg b PO4, or Mn 1-a-b Fe a V b1 Ti b2 PO4, b1+b2=b, 10 -4 ≦b1≦10 -2 , 10 -4 ≦b2≦10 -2 , 10 -4 ≦b3≦10 -2 , 10 -4 ≦b4≦10 -2 is.

[0022] In some embodiments, the chemical formula of the phosphate-based material is Mn 0.6 Fe 0.395 Co 0.005 PO4 or Mn 0.65 Fe 0.344 Mg 0.005 B 0.001 PO4 or Mn 0.7 Fe 0.293 Mo 0.003 Nb 0.003 B 0.001 PO4 or Mn 0.8 Fe 0.19 Co 0.005 V 0.001 Ni 0.001 B 0.003 PO4 or Mn 0.5 Fe 0.495 Mg 0.005 PO4 or Mn 0.65 Fe 0.34 V 0.005 Ti 0.005 PO 4である .

[0023] In some embodiments, M is five or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium, and the phosphate-based material is a high-entropy doped ferromanganese phosphate material.

[0024] In some embodiments, the chemical formula of the phosphate-based material is Mn 1-a-b Fe a Mg b1 V b2 Ti b3 Cr b4 Co b5 PO4, Mn 1-a-b Fe a Zn b1 Cu b2 Mg b3 Co b4 Ti b5 PO4, Mn 1-a-b Fe a Zn b1 Cu b2 Mg b3 Mo b4 Ti b5 PO4, Mn 1-a-b Fe a Mg b1 V b2 Ti b3 Cr b4 Mo b5 PO4, Mn 1-a-b Fe a Nb b1 B b2 Co b3 V b4 Al b5 PO4, Mn 1-a-b Fe a Co b1 V b2 Ni b3 B b4 Nb b5 PO4, Mn 1-a-b Fe a Co b1 Ga b2 Bb3 Al b4 Sr b5 PO4 or Mn 1-a-b Fe a Mo b1 Co b2 Ni b3 V b4 Ca b5 PO4, b1+b2+b3+b4+b5=b, and the range of b1 to b5 is 10 -4 ≦b1≦10 -2 , 10 -4 ≦b2≦10 -2 , 10 -4 ≦b3≦10 -2 , 10 -4 ≦b4≦10 -2 , 10 -4 ≦b5≦10 -2 is.

[0025] In some embodiments, the chemical formula of the phosphate-based material is Mn 0.7 Fe 0.293 Mg 0.015 V 0.001 Ti 0.0005 Cr 0.001 Co 0.003 PO4, Mn 0.6 Fe 0.395 Zn 0.001 Cu 0.0005 Mg 0.001 Co 0.002 Ti 0.0005 PO4, Mn 0.6 Fe 0.39 Zn 0.001 Cu 0.0005 Mg 0.005 Mo 0.003 Ti 0.0005 PO4, Mn 0.7 Fe 0.293 Mg 0.0015 V 0.001 Ti 0.0005 Cr 0.001 Mo 0.003 PO4, Mn 0.7 Fe 0.29 Nb 0.003 B 0.003 Co 0.001 V 0.002 Al 0.001 PO4, Mn 0.8 Fe0.19 Co 0.005 V 0.001 Ni 0.0005 B 0.003 Nb 0.0005 PO4, Mn 0.5 Fe 0.49 Co 0.0025 Ga 0.0005 B 0.003 Al 0.002 Sr 0.002 PO4 or Mn 0.65 Fe 0.34 Mo 0.003 Co 0.003 Ni 0.002 V 0.0015 Ca 0.0005 It is PO4.

[0026] The present invention further provides a method for producing a phosphate-based material, the method comprising the steps of: 1) mixing manganese iron oxide and a compound of any element M with phosphoric acid to obtain a reaction mixture; 2) grinding the reaction mixture to react with the reaction mixture to produce a phosphate, thereby obtaining a slurry containing the phosphate, wherein the particle size of the phosphate in the slurry is 100 nm or less; 3) separating the slurry to obtain phosphate particles; and 4) separating the phosphate particles. After drying and sintering, the phosphate-based material is obtained, wherein M is one or a combination of M selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium.

[0027] In some embodiments, the particle size of the manganese iron oxide is 1 to 20 μm, and preferably, the particle size of the manganese iron oxide is 2 to 7 μm.

[0028] In some embodiments, the phosphoric acid is present in the form of an aqueous phosphoric acid solution, and the mass concentration of the aqueous phosphoric acid solution is 10% to 70%, preferably 20% to 40%.

[0029] In some embodiments, the molecular formula of the manganese iron oxide is (Mn x Fe y )3O4, where 0.50≦x≦0.81 and 0.19≦y≦0.50.

[0030] In some embodiments, the molecular formula of the manganese iron oxide is (Mn 0.60 Fe 0.40 )3O4, (Mn 0.61 Fe 0.39 )3O4, (Mn 0.65 Fe 0.35 )3O4, (Mn 0.70 Fe 0.30 )3O4, (Mn 0.71 Fe 0.29 )3O4, (Mn 0.81 Fe 0.19 )3O4, (Mn 0.50 Fe 0.50 )3O4, (Mn 0.51 Fe 0.49 )3O4 or (Mn 0.66 Fe 0.34 )3O4.

[0031] In some embodiments, in step 1), the mixing is carried out with mechanical stirring at a temperature of 20 to 40°C.

[0032] In some embodiments, in step 1), the mixing time is 1 to 12 hours.

[0033] In some embodiments, in step 2), the polishing is performed in a sand mill, and the polishing temperature is 20 to 40°C.

[0034] In some embodiments, in step 2), the polishing time is 0.5 to 3 hours.

[0035] In some embodiments, in step 4), the drying temperature is 100 to 120°C.

[0036] In some embodiments, in step 4), the drying time is 10 hours.

[0037] In some embodiments, in step 4), the sintering temperature is 300 to 400°C.

[0038] In some embodiments, in step 4), the sintering time is 1 to 4 hours.

[0039] In some embodiments, step 3) comprises filtering and washing the phosphate slurry.

[0040] In some embodiments, step 4) includes drying the phosphate particles to obtain ferrous manganese phosphate monohydrate crystals or doped ferrous manganese phosphate monohydrate crystals having particles of 100 nm or less, and sintering the ferrous manganese phosphate monohydrate crystals or doped ferrous manganese phosphate monohydrate crystals to obtain the phosphate-based material.

[0041] In some embodiments, the ratio of the total amount of the manganese iron oxide and the compound of element M to the amount of the phosphoric acid is 1:1-2.

[0042] In some embodiments, the production method further comprises, before step 1), pre-dispersing the manganese iron oxide in an aqueous dispersant solution.

[0043] In some embodiments, the dispersing agent is one or a combination of more selected from polyvinylpyrrolidone, polyethylene glycol, and TC130 dispersing agent.

[0044] In some embodiments, the mass concentration of the dispersant aqueous solution is 0.01% to 5%.

[0045] In some embodiments, the method further comprises, before step 1), a step of reacting phosphorus pentoxide with water to produce the phosphoric acid. That is, the present invention may use phosphoric acid or phosphorus pentoxide as a phosphorus source for producing a phosphate-based material.

[0046] In some embodiments, the compound of element M is one or a combination of compounds selected from a compound of magnesium, a compound of titanium, a compound of vanadium, a compound of cobalt, a compound of nickel, a compound of zinc, a compound of gallium, a compound of aluminum, a compound of zirconium, a compound of niobium, a compound of molybdenum, a compound of tin, a compound of antimony, a compound of calcium, a compound of barium, a compound of strontium, a compound of boron, a compound of ruthenium, a compound of silicon, a compound of tellurium, a compound of niobium, a compound of copper, and a compound of lithium.

[0047] In some embodiments, the compound of element M is one or a combination of a plurality of compounds selected from oxides, carbonates, oxalates, nitrates, sulfates, chlorides, and organic acid salts of element M.

[0048] In some embodiments, the organic acid salt of element M is one or a combination of a plurality of organic phosphates, acetates, organic sulfonates, alkyl salts, and ester salts of other metal elements.

[0049] Preferably, the compound of element M is an oxide, an acetate, or a carbonate.

[0050] In some embodiments, the compound of element M is cobalt chloride; or a combination of magnesium oxide and boric acid; or a combination of molybdenum trioxide, niobium oxalate and boric acid; or a combination of cobalt acetate, ammonium metavanadate, nickel sulfate and boric acid; or magnesium acetate; or a combination of vanadyl oxalate and titanium chloride.

[0051] In some embodiments, the compound of element M is a combination of five or more selected from a compound of magnesium, a compound of titanium, a compound of vanadium, a compound of cobalt, a compound of nickel, a compound of zinc, a compound of gallium, a compound of aluminum, a compound of zirconium, a compound of niobium, a compound of molybdenum, a compound of tin, a compound of antimony, a compound of calcium, a compound of barium, a compound of strontium, a compound of boron, a compound of ruthenium, a compound of silicon, a compound of tellurium, a compound of niobium, a compound of copper, and a compound of lithium.

[0052] In some embodiments, the compound of element M is a combination of magnesium acetate, ammonium metavanadate, titanium oxide, cadmium oxide, and cobalt sulfate; a combination of zinc sulfate, copper oxalate, cobalt acetate, magnesium nitrate, cobalt oxide, and n-butyl titanate; a combination of zinc oxide, copper oxide, magnesium oxide, molybdenum oxide, and titanium dioxide; or a combination of magnesium oxide, ammonium metavanadate, and titanium dioxide. or a combination of niobium oxalate, boron oxide, cobalt acetate, ammonium metavanadate, and aluminum oxide; or a combination of cobalt acetate, ammonium metavanadate, nickel acetate, boric acid, and niobium oxalate; or a combination of cobalt chloride, gallium chloride, boric acid, chromium oxide, and strontium chloride; or a combination of molybdenum oxide, cobalt chloride, nickel chloride, vanadium oxalate, and calcium oxide.

[0053] The present invention further provides an application of the ferromanganese phosphate or phosphate-based material, or a phosphate-based material obtained by the method for producing a phosphate-based material, to the production of a battery positive electrode material.

[0054] The present invention further provides a manganese iron phosphate-based battery positive electrode material obtained by subjecting raw materials containing the ferromanganese phosphate or phosphate-based material or the phosphate-based material obtained by the method for producing a phosphate-based material, a lithium source (based) compound, and an arbitrary organic carbon source to a high-temperature sintering reaction.

[0055] In some embodiments, the lithium source compound is one or a combination of more selected from lithium carbonate, lithium hydroxide, lithium chloride, lithium sulfate, lithium nitrate, lithium dihydrogen phosphate, lithium dihydrogen phosphate, and lithium acetate.

[0056] In some embodiments, the organic carbon source is one or a combination of more selected from glucose, sucrose, fructose, citric acid, polyethylene glycol, polyvinylpyrrolidone, ethylenediaminetetraacetic acid, and ascorbic acid.

[0057] The present invention further provides a lithium ion battery comprising a cathode material containing the manganese iron phosphate-based cathode material, which has excellent cycle performance.

[0058] In some embodiments, the lithium ion battery has a discharge specific capacity of 145 mAh / g or more at 0.1C, a discharge specific capacity of 135 mAh / g or more at 1C, and a capacity retention rate of 92% or more after 200 charge / discharge cycles at 1C.

[0059] In some embodiments, the lithium ion battery has a discharge specific capacity of 145.2 mAh / g or more at 0.1 C, a discharge specific capacity of 135.7 mAh / g or more at 1 C, and a capacity retention rate of 92.9% or more after 200 charge / discharge cycles at 1 C.

[0060] In some embodiments, the lithium ion battery has a discharge specific capacity of 150 mAh / g or more at 0.1 C, a discharge specific capacity of 140 mAh / g or more at 1 C, and a capacity retention rate of 95.6% or more after 200 charge / discharge cycles at 1 C. [Effects of the Invention]

[0061] Compared with the prior art, the present invention has the following advantages:

[0062] The ferromanganese phosphate material or phosphate-based material of the present invention has a small particle size at the nano-level and a porous structure. When the ferromanganese phosphate material is used as a precursor for a manganese iron phosphate-based battery cathode material, and the resulting manganese iron phosphate-based battery cathode material is used in a lithium ion battery, the specific capacity, power supply ratio, and cycle performance of the battery are all significantly improved. [Brief explanation of the drawings]

[0063] [Figure 1] FIG. 1 is an XRD diagram of the manganese iron oxide raw material used in Example 1. [Figure 2] , [Figure 3] 2 and 3 are SEM images of the manganese oxide iron raw material used in Example 1, and the scales of the two are different. [Figure 4] FIG. 4 is an XRD diagram of the ferric manganese phosphate monohydrate in Example 1. [Figure 5] , [Figure 6] 5 and 6 are SEM images of the ferric manganese phosphate monohydrate in Example 1, with scales of 1 μm and 2 μm, respectively. [Figure 7] FIG. 7 is an XRD diagram of the ferromanganese phosphate produced in Example 1. [Figure 8] FIG. 8 is an SEM image of the ferromanganese phosphate produced in Example 1. [Figure 9] FIG. 9 is an XRD diagram of the product of step 2) in Comparative Example 1. [Figure 10] , [Figure 11] 10 and 11 are SEM images of the product of step 2) in Comparative Example 1, and the scales of the two images are different. [Figure 12] FIG. 1 is an XRD diagram of the final product in Comparative Example 1. [Figure 13] FIG. 13 is an SEM image of the final product in Comparative Example 1. [Figure 14] FIG. 14 is a graph showing the adsorption and desorption curves of ferromanganese phosphate produced in Example 1. [Figure 15] FIG. 15 is a pore size distribution map of the ferromanganese phosphate produced in Example 1. [Figure 16] , [Figure 17] 16 and 17 are SEM images of the product of step 2) in Comparative Example 2, and the scales of the two images are different. [Figure 18] FIG. 18 is an SEM image of the final product in Comparative Example 2. [Figure 19] FIG. 19 shows the results of a magnification test using Example 1 in a button battery. [Figure 20] FIG. 20 shows the results of a cycle test using Example 1 in a button battery. [Figure 21] FIG. 21 is an XRD diagram of the doped modified manganese ferric phosphate monohydrate in Example 8. [Figure 22] , [Figure 23] 22 and 23 are SEM images of the doped modified manganese ferric phosphate monohydrate in Example 8, with scales of 1 μm and 2 μm, respectively. [Figure 24] FIG. 24 is an XRD diagram of the doped modified ferromanganese phosphate prepared in Example 8. [Figure 25] FIG. 25 is an SEM image of the doped modified ferromanganese phosphate prepared in Example 8. [Figure 26] FIG. 26 is an XRD diagram of the product of step 2) in Comparative Example 4. [Figure 27] , [Figure 28] 27 and 28 are SEM images of the product of step 2) in Comparative Example 4, and the scales of the two images are different. [Figure 29] FIG. 29 is an XRD diagram of the final product in Comparative Example 4. [Figure 30]FIG. 30 is an SEM image of the final product in Comparative Example 4. [Figure 31] FIG. 31 is a graph showing the adsorption and desorption curves of the doped modified ferromanganese phosphate prepared in Example 8. [Figure 32] FIG. 32 is a pore size distribution map of the doped modified ferromanganese phosphate obtained in Example 8. [Figure 33] FIG. 33 shows the results of a magnification test using Example 8 in a button battery. [Figure 34] FIG. 34 shows the results of a cycle test using Example 8 in a button battery. [Figure 35] FIG. 35 is an XRD diagram of the manganese iron oxide raw material used in Example 14. [Figure 36] , [Figure 37] 36 and 37 are SEM images of the manganese-iron oxide raw material used in Example 14, and the scales of the two are different. [Figure 38] FIG. 38 is an XRD diagram of the doped ferric manganese phosphate monohydrate in Example 14. [Figure 39] , [Figure 40] 39 and 40 are SEM images of the doped ferric manganese phosphate monohydrate in Example 14, with scales of 1 μm and 2 μm, respectively. [Figure 41] FIG. 41 is an XRD diagram of the doped ferromanganese phosphate obtained as prepared in Example 14. [Figure 42] FIG. 42 is an SEM image of the doped ferromanganese phosphate obtained as prepared in Example 14. [Figure 43] FIG. 43 is an XRD diagram of the product of step 2) in Comparative Example 6. [Figure 44] , [Figure 45] 44 and 45 are SEM images of the product of step 2) in Comparative Example 6, and the scales of the two images are different. [Figure 46] FIG. 46 is an XRD diagram of the final product in Comparative Example 6. [Figure 47]FIG. 47 is an SEM image of the final product in Comparative Example 6. [Figure 48] FIG. 48 is a graph showing the adsorption and desorption curves of the doped ferromanganese phosphate obtained in Example 14. [Figure 49] FIG. 49 is a pore size distribution map of the doped ferromanganese phosphate obtained as prepared in Example 14. [Figure 50] FIG. 50 shows the results of a magnification test using Example 14 in a button battery. [Figure 51] FIG. 51 shows the results of a cycle test using Example 14 in a button battery. DETAILED DESCRIPTION OF THE INVENTION

[0064] The present invention provides an improved ferromanganese phosphate, the main innovation of which is that its particle size is controlled to 50 nm or less and it has a porous structure. Prior art discloses ferromanganese phosphate, but its particle size is on the micron level, making it large. Furthermore, the ferromanganese phosphate particles in the prior art are dense and usually non-porous. In the present invention, when the ferromanganese phosphate with a small particle size and a porous structure is used to prepare a ferromanganese phosphate-based positive electrode material, the specific capacity, charge / discharge ratio, and cycle performance of the final lithium-ion battery containing the positive electrode material are all significantly improved.

[0065] Another innovation of the present invention is to dope ferromanganese phosphate with five or more doping metals to obtain a doped ferromanganese phosphate material, and then sinter the doped ferromanganese phosphate material with a lithium source and an organic carbon source at high temperature to obtain a high-entropy doped ferromanganese phosphate-based positive electrode material. The site of the ferromanganese active element in the structure of the positive electrode material is occupied by five or more doped metal elements, and the positive electrode material has a high-entropy effect. Specifically, 1) the high-entropy material composed of multiple elements forms a single-phase solid solution rather than a mixture of different phases or multiple solid solutions, making the material more thermodynamically stable; 2) the atoms within the high-entropy material are randomly distributed within the crystal lattice, with different metal atomic radii and chemical bonds varying significantly, and the surrounding environments and sites of each atom being different. This results in greater distortion and defects within the crystal lattice than those of conventional one-component or two-component phosphate materials, resulting in higher material activity and therefore higher electrochemical activity; 3) a dynamic hysteresis diffusion effect exists, i.e., the internal diffusion and phase change rates of high-entropy materials are very slow; and 4) the basic properties of the various components and the interactions between them allow high-entropy materials to exhibit more complex properties, resulting in richer material performance. Therefore, due to the influence of the high-entropy effect, the performance of high-entropy doped phosphate-based positive electrode materials is far superior to that of the corresponding binary metal elements, such as ferromanganese phosphate-based positive electrode materials. The high-entropy doped ferromanganese phosphate-based positive electrode materials have a more stable crystal structure, which makes it difficult for metal ions such as manganese to be dissolved, and further improves the cycle performance of the materials. The presence of multi-component active metals also contributes to the improvement of the cycle performance of the materials. The synergy between the active metals and the active metals increases the number of electrochemical platforms in the cathode material, and the interconnections between the platforms become smoother, eliminating the sudden drop in the discharge platform edge. The high-entropy doped ferromanganese phosphate cathode material also has a higher electron and ion conduction rate, which may improve the later charging performance when used in lithium-ion batteries.

[0066] Another innovation of the present invention lies in the manufacturing process for ferromanganese phosphate material. In the present invention, manganese iron oxide is directly mixed with phosphoric acid, and then polished to accelerate the reaction between the two, resulting in a nano-scale phosphate slurry. After separating particles from the slurry, the particles are dried to obtain nano-scale crystalline manganese ferric phosphate monohydrate, which is finally sintered to obtain the nanoporous ferromanganese phosphate of the present invention. Compared to conventional techniques, this manufacturing process does not require a reducing agent or a soluble ferrous salt as a reaction raw material. However, by directly reacting phosphoric acid with manganese iron oxide, a compound in which manganese iron elements are uniformly mixed at the atomic level, high-purity ferromanganese phosphate can be obtained, resulting in a simpler process. The polishing accelerates the reaction; without polishing, the reaction between manganese iron oxide and phosphoric acid is very slow, the reaction period is very long, and it is difficult to achieve a thorough reaction.

[0067] Another innovation of the present invention is that by changing the concentration of phosphoric acid, the dissolution rate of manganese iron oxide and the nucleation rate of ferromanganese phosphate can be controlled, and the crystal particle size of ferromanganese phosphate can be further adjusted. The phosphoric acid here can be obtained by reacting phosphorus pentoxide with water, i.e., either phosphoric acid or phosphorus pentoxide can be used as the phosphorus source when producing the ferromanganese phosphate of the present invention.

[0068] Another innovation of the present invention is that compounds of at least five other doped metal elements and manganese iron oxide can be mixed with phosphoric acid and the subsequent process can be carried out to produce and obtain the doped ferromanganese phosphate material of the present invention. [Example]

[0069] The present invention will be further described below with reference to examples. However, the present invention is not limited to the following examples. The operating conditions adopted in the examples can be further adjusted according to different requirements of specific use, and the operating conditions not specified are general conditions in the industry. The technical features according to various embodiments of the present invention can be combined with each other as long as they are not contradictory to each other. Example 1

[0070] In this example, the chemical formula is Mn 0.6 Fe 0.4 A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0071] 1) Add concentrated phosphoric acid solution and deionized water in order into a glass beaker and stir evenly. Then, prepare a 35% mass concentration phosphoric acid aqueous solution. The molar ratio of P element is 1:1.5, which is the sum of Mn and Fe. Add 50 g of micron-level manganese iron oxide (molecular formula (Mn)) to 275 mL of the phosphoric acid aqueous solution. 0.60 Fe 0.40 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0072] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0073] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0074] The XRD and SEM images of manganese iron oxide are shown in Figures 1, 2, and 3, respectively. As can be seen from these, manganese iron oxide has a crystalline structure. The XRD and SEM images of the ferric manganese phosphate monohydrate obtained in step 2 are shown in Figures 4, 5, and 6, respectively. As can be seen from these, its crystalline phase is MnPO4·H2O with a monoclinic structure. Measurement by scanning electron microscope (SEM) testing revealed that the particle size of the ferric manganese phosphate monohydrate was 20 nm. The XRD and SEM images of the ferromanganese phosphate obtained in step 3 are shown in Figures 7 and 8, respectively. As can be seen from these, the ferromanganese phosphate has a certain degree of crystallinity and a large amount of porous structure is distributed between the particles. As can be seen from the XRD test, the crystalline phase still maintains a monoclinic phase structure. As measured by scanning electron microscope (SEM) testing, the particle size of ferromanganese phosphate is 40nm. At the same time, an adsorption / desorption test and analysis of ferromanganese phosphate are also carried out using a specific surface area and aperture tester. As can be seen from Figures 14 and 15, the ferromanganese phosphate material has a mesoporous structure, with the pore size mainly distributed between 3 and 5nm, and its specific surface area is 15m. 2 / g.

[0075] In this example, the chemical formula is Mn 0.85 Fe 0.15 A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0076] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker, and after stirring evenly, a 70% mass concentration phosphoric acid aqueous solution was prepared. In another glass beaker, polyvinylpyrrolidone and deionized water were added in this order, and after stirring evenly, a 0.1% mass concentration polyvinylpyrrolidone aqueous solution was prepared. The molar ratio of P element was 1:1.5, with the sum of Mn and Fe. 76.4 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 280 mL of the polyvinylpyrrolidone aqueous solution. 0.85 Fe 0.15 )3O4, purchased from Sichuan Qingyuan New Materials Co., Ltd., with an average particle size of 7 μm, was poured into the solution and mechanically stirred for 30 minutes to obtain a black aqueous suspension. 210 g of the above phosphoric acid solution was slowly poured into the above suspension. After the phosphoric acid solution was completely poured, the mixture was mechanically stirred for 12 hours to obtain a reaction mixture.

[0077] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0078] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0079] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 45 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 5 nm, and its specific surface area was 14.5 m 2 / g. Example 3

[0080] In this example, the chemical formula is Mn 0.72 Fe 0.28A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0081] 1) Add concentrated phosphoric acid solution and deionized water in a glass beaker in that order and stir evenly. In another glass beaker, polyethylene glycol and deionized water were added in that order and stirred uniformly, after which a polyethylene glycol aqueous solution with a mass concentration of 5% was prepared. The molar ratio of P element was set to 1:1.5 with the sum of Mn and Fe. 76.52 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 245 mL of the polyethylene glycol aqueous solution. 0.72 Fe 0.28 )3O4, purchased from Sichuan Qingyuan New Materials Co., Ltd., with an average particle size of 7 μm, was poured into the solution and mechanically stirred for 30 minutes to obtain a black aqueous suspension. 245 g of the above phosphoric acid solution was slowly poured into the above suspension. After the phosphoric acid solution was completely poured, the mixture was mechanically stirred for 12 hours to obtain a reaction mixture.

[0082] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0083] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0084] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 20 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 40 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 3 and 5 nm, and its specific surface area was 15.1 m 2 / g. Example 4

[0085] In this example, the chemical formula is Mn 0.65 Fe 0.35 A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0086] 1) A concentrated phosphoric acid solution and deionized water were added in a glass beaker in this order and stirred uniformly. Then, a 40% mass concentration phosphoric acid aqueous solution was prepared. The total of Mn and Fe was used to make the P element molar ratio 1:2. 76.59 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 490 mL of the phosphoric acid aqueous solution. 0.65 Fe 0.35 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0087] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0088] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0089] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 10 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 20 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 2 and 4 nm, and its specific surface area was 17 m 2 / g.

[0090] In this example, the chemical formula is Mn 0.99 Fe 0.01A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0091] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 20% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P was 1:1.2, which is the sum of Mn and Fe. 72.3 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 588 mL of the phosphoric acid aqueous solution. 0.99 Fe 0.01 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0092] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0093] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0094] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 30 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 50 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 5 and 8 nm, and its specific surface area was 13.8 m 2 / g. Example 6

[0095] In this example, the chemical formula is Mn 0.5 Fe 0.5 A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0096] 1) A concentrated phosphoric acid solution and deionized water were added in a glass beaker in this order and stirred uniformly. Then, a 30% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 76.72 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 490 mL of the phosphoric acid aqueous solution. 0.5 Fe 0.5 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0097] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0098] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0099] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 15 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 30 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 3 and 5 nm, and its specific surface area was 16.4 m 2 / g. Example 7

[0100] In this example, the chemical formula is Mn 0.01 Fe 0.99 A nanoporous ferromanganese phosphate (PO4) is provided, and the manufacturing process is as follows:

[0101] 1) Add concentrated phosphoric acid solution and deionized water in a glass beaker in that order and stir evenly. Then, prepare a 40% mass concentration phosphoric acid aqueous solution. The molar ratio of P is the sum of Mn and Fe. 77.16 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 294 mL of the above phosphoric acid solution at a ratio of 1:1.2. 0.01 Fe 0.99 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0102] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain dark green ferric manganese phosphate monohydrate.

[0103] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain ferromanganese phosphate with a reddish-brown nanoporous structure.

[0104] After testing and analysis, it was found that the obtained manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 50 nm. The ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 3 and 5 nm, and its specific surface area was 15.4 m 2 / g. Comparative Example 1

[0105] In this comparative example, a comparative phosphate material is provided, and the manufacturing process thereof is basically the same as that of Example 1, and the details are as follows:

[0106] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 35% mass concentration aqueous phosphoric acid solution was prepared, with the total of Mn and Fe being the P element molar ratio of 1:1.5. 265 mL of the above aqueous phosphoric acid solution was added with a mixture of 34.38 g of manganese oxide and 15.62 g of iron oxide (the Mn to Fe molar ratio was 6.9:3.1, and the particle sizes of the manganese oxide and iron oxide were both 7 μm), and the mixture was mechanically stirred for 12 hours to obtain a reaction mixture.

[0107] 2) Pour the reaction mixture into a sand mill and sand for 1 hour to obtain a dark brown slurry, filter and wash the slurry to obtain particles, and then dry the particles at 100°C to obtain a dark brown product.

[0108] 3) The product of step 2) is sintered in a muffle furnace at 400°C for 2 hours to obtain a dark brown final product.

[0109] The XRD and SEM images of the product obtained in step 2) are shown in Figures 9, 10-11, respectively. As can be seen, the product is a mixture of manganese phosphate monohydrate (MnPO4·H2O) and iron oxide, and the particle size distribution of the product is not uniform, ranging from 50 to 1000 nm, with the smallest particles of about 50 nm being MnPO4·H2O and the largest particles of about 1000 nm being iron oxide. The XRD and SEM images of the final product obtained in step 3) are shown in Figures 12 and 13, respectively. As can be seen, the final product is a mixture of manganese phosphate and iron oxide with low crystallinity, and the particle size distribution of the final product is not uniform, ranging mainly from 50 to 1000 nm, with many pores between the small particles and a relatively high density of large particles. Comparative Example 2

[0110] In this comparative example, a comparative phosphate material is provided, and the manufacturing process thereof is basically the same as that of Example 1, and the details are as follows:

[0111] 1) A concentrated phosphoric acid solution and deionized water are added in this order to a glass beaker and stirred uniformly. Then, a 35% mass concentration aqueous phosphoric acid solution is prepared, with the total of Mn and Fe making the P element molar ratio 1:1.5. A mixture of 47.36 g of manganese (III) oxide and 31.94 g of iron (III) oxide (the particle sizes of the manganese oxide and iron oxide are both 7 μm, and the molar ratio of Mn to Fe is 6:4) is poured into 420 mL of the above aqueous phosphoric acid solution, and mechanically stirred for 12 hours to obtain a reaction mixture.

[0112] 2) Pour the reaction mixture into a sand mill and sand for 1 hour to obtain a dark brown slurry, filter and wash the slurry to obtain particles, and then dry the particles at 100°C to obtain a dark brown product.

[0113] 3) The product of step 2) is sintered in a muffle furnace at 400°C for 2 hours to obtain a dark brown final product.

[0114] The product obtained in step 2) is a mixture of manganese phosphate monohydrate (MnPO4·H2O) and iron oxide, and the particle size distribution of the product is not uniform, ranging from 30 to 1000 nm, with the smallest particles of around 30 nm being MnPO4·H2O and the largest particles of around 1000 nm being iron oxide, as shown in SEM images in Figures 16 and 17. The final product obtained in step 3) is a mixture of manganese phosphate and iron oxide with low crystallinity, as shown in SEM image in Figure 18. As can be seen, the primary particle size distribution of the final product is also not uniform, ranging mainly from 50 to 800 nm, with many pores between the small particles and a relatively high density of large particles. Comparative Example 3

[0115] In this comparative example, a comparative phosphate material is provided, and its manufacturing process is basically the same as that of Example 1, except that polishing is not performed in step 2). The manufacturing process is specifically as follows:

[0116] 1) Add concentrated phosphoric acid solution and deionized water in order into a glass beaker and stir evenly. Then, prepare a 35% mass concentration phosphoric acid aqueous solution. The molar ratio of P element is 1:1.5, which is the sum of Mn and Fe. Add 50 g of micron-level manganese iron oxide (molecular formula (Mn)) to 275 mL of the phosphoric acid aqueous solution. 0.60 Fe 0.40 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0117] 2) The reaction mixture is filtered and washed to obtain particles, which are then dried at 100°C to obtain a black powder material.

[0118] 3) The black powder material is sintered in a muffle furnace at 400°C for 2 hours to obtain a brown-black powder material.

[0119] The black powder material obtained in step 2) is still mainly composed of manganese iron oxide with a small amount of ferromanganese phosphate monohydrate, while the brown-black powder material obtained in step 3) is also mainly composed of manganese iron oxide with a small amount of ferromanganese phosphate. Example 8

[0120] In this example, the chemical formula is Mn 0.6 Fe 0.395 Co 0.005 A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0121] 1) Add concentrated phosphoric acid solution and deionized water in a glass beaker in that order and stir evenly. The phosphoric acid solution was prepared with a mass concentration of 35%, and the molar ratio of P element was 1:1.5, based on the total of Mn and Fe. 114.95 g of micron-level manganese iron oxide (molecular formula (Mn) 0.60 Fe 0.40)3O4, purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 1.190 g of cobalt chloride hexahydrate was poured into the mixture, and the mixture was mechanically stirred for 12 hours to obtain a reaction mixture.

[0122] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (manganese iron cobalt phosphate monohydrate).

[0123] 3) Ferromanganese cobalt phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain reddish-brown powder ferromanganese cobalt phosphate.

[0124] The XRD and SEM images of the manganese iron cobalt phosphate monohydrate obtained in step 2 are shown in Figures 21, 22 and 23, respectively. As can be seen from these, the crystal phase is MnPO4·H2O with a monoclinic structure. Measurement by scanning electron microscope (SEM) testing method revealed that the particle size of the manganese iron cobalt phosphate monohydrate was 20 nm. The XRD and SEM images of the ferromanganese cobalt phosphate obtained in step 3 are shown in Figures 24 and 25, respectively. As can be seen from these, the ferromanganese cobalt phosphate has a certain degree of crystallinity, and a large amount of porous structure is distributed between the particles. As can be seen from the XRD test, the crystalline phase still maintains a monoclinic phase structure. The measurement result of the scanning electron microscope (SEM) test method shows that the particle size of the ferromanganese cobalt phosphate is 40nm. At the same time, the adsorption and desorption test and analysis of the ferromanganese cobalt phosphate are carried out using a specific surface area and aperture tester. As can be seen from Figures 31 and 32, the ferromanganese cobalt phosphate material has a mesoporous structure, with the pore size mainly distributed between 3 and 5nm, and its specific surface area is 15.1m 2 / g. Example 9

[0125] In this example, the chemical formula is Mn 0.65 Fe 0.344 Mg 0.005 B 0.001A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0126] 1) A concentrated phosphoric acid solution and deionized water were added in a glass beaker in this order and stirred uniformly. Then, a 30% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.88 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 735 mL of the phosphoric acid aqueous solution. 0.65 Fe 0.35 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.201 g of magnesium oxide, and 0.062 g of boric acid were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0127] 2) Pour the reaction mixture into a sand mill and sand for 1 hour to obtain a dark green slurry, filter and wash the slurry to obtain particles, and dry the particles at 100°C to obtain a dark green powder (magnesium boron-doped ferric manganese phosphate monohydrate).

[0128] 3) The magnesium boron doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish brown powder.

[0129] Through testing and analysis, it was found that the obtained magnesium boron doped ferromanganese phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, the particle size was 25 nm, and the heat-treated magnesium boron doped ferromanganese phosphate had a certain degree of crystallinity. The crystalline phase still maintains a monoclinic phase structure, and a large amount of porous structure is distributed between the particles. The particle size is 45 nm. The magnesium boron doped ferromanganese phosphate material has a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area is 14.8 m 2 / g. Example 10

[0130] In this example, the chemical formula is Mn0.7 Fe 0.293 Mo 0.003 Nb 0.003 B 0.001 A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0131] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P was 1:1.5, which is the sum of Mn and Fe. 114.81 g of micron-level manganese iron oxide (molecular formula (Mn) 0.70 Fe 0.30 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.432 g of molybdenum trioxide, 1.614 g of niobium oxalate, and 0.062 g of boric acid were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0132] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (molybdenum, niobium, and boron-doped manganese ferric phosphate monohydrate).

[0133] 3) The molybdenum, niobium, and boron-doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0134] After testing and analysis, it was found that the obtained molybdenum niobium boron doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 30nm. After heat treatment, the molybdenum niobium boron doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 50nm. The molybdenum niobium boron doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 6nm, and its specific surface area was 14.1m2 / g. Example 11

[0135] In this example, the chemical formula is Mn 0.8 Fe 0.19 Co 0.005 V 0.001 Ni 0.001 B 0.003 A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0136] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 30% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was set to 1:1.5, which is the sum of Mn and Fe. 114.66 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 735 mL of the phosphoric acid aqueous solution. 0.81 Fe 0.19 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 1.245 g of cobalt acetate tetrahydrate, 0.117 g of ammonium metavanadate, 0.263 g of nickel sulfate hexahydrate, and 0.185 g of boric acid were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0137] 2) The reaction mixture was poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which was then filtered and washed to obtain particles, which were then dried at 100°C to obtain a dark green powder (cobalt vanadium nickel boron doped phosphorus). Obtain ferric manganese oxide monohydrate.

[0138] 3) The cobalt vanadium nickel boron doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish brown powder.

[0139] After testing and analysis, it was found that the obtained cobalt vanadium nickel boron doped ferromanganese phosphate ferric monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 20nm. After heat treatment, the cobalt vanadium nickel boron doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 40nm. The cobalt vanadium nickel boron doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 3 and 5nm, and its specific surface area was 15.8m 2 / g. Example 12

[0140] In this example, the chemical formula is Mn 0.5 Fe 0.495 Mg 0.005 A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0141] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 115.08 g of micron-level manganese iron oxide (molecular formula (Mn) 0.50 Fe 0.50 )3O4, purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 1.072 g of magnesium acetate tetrahydrate was poured into the mixture, and the mixture was mechanically stirred for 12 hours to obtain a reaction mixture.

[0142] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (magnesium ferromanganese phosphate monohydrate).

[0143] 3) Ferromanganese magnesium phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0144] After testing and analysis, it was found that the obtained ferromanganese magnesium phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the ferromanganese magnesium phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 45 nm. The ferromanganese magnesium phosphate had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 15.1 m 2 / g. Example 13

[0145] In this example, the chemical formula is Mn 0.65 Fe 0.34 V 0.005 Ti 0.005 A nanoporous doped modified ferromanganese phosphate (PO4) is provided, and the preparation process is as follows:

[0146] 1) A concentrated phosphoric acid solution and deionized water were added in that order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.87 g of micron-level manganese iron oxide (molecular formula (Mn) 0.66 Fe 0.34 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 1.225 g of vanadyl oxalate, and 0.948 g of titanium chloride were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0147] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (vanadium titanium doped ferric manganese phosphate monohydrate).

[0148] 3) The vanadium-titanium doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0149] After testing and analysis, it was found that the obtained vanadium titanium doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the vanadium titanium doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 45 nm. The vanadium titanium doped ferromanganese phosphate had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 14.8 m 2 / g. Comparative Example 4

[0150] In this comparative example, a comparative phosphate material is provided, and the manufacturing process thereof is basically the same as that of Example 8, and the details are as follows:

[0151] 1) A concentrated phosphoric acid solution and deionized water are added in this order to a glass beaker and stirred uniformly. Then, a 35% mass concentration aqueous phosphoric acid solution is prepared, with the total of Mn and Fe, and the P element molar ratio is 1:1.5. 47.36 g of a mixture of manganese (III) oxide, 31.94 g of iron (III) oxide (particle sizes of both manganese oxide and iron oxide are 7 μm), and 1.190 g of cobalt chloride hexahydrate are poured into 420 mL of the above aqueous phosphoric acid solution, and the mixture is mechanically stirred for 12 hours to obtain a reaction mixture.

[0152] 2) Pour the reaction mixture into a sand mill and sand for 1 hour to obtain a dark brown slurry, filter and wash the slurry to obtain particles, and then dry the particles at 100°C to obtain a dark brown product.

[0153] 3) The product of step 2) is sintered in a muffle furnace at 400°C for 2 hours to obtain a dark brown final product.

[0154] The XRD and SEM images of the product obtained in step 2 are shown in Figures 26, 27, and 28, respectively. As can be seen, the product is a mixture of cobalt-doped manganese phosphate monohydrate (MnPO4·H2O) and iron oxide. The particle size distribution of the product is not uniform, ranging from 30 to 2000 nm. The small particles of about 30 nm are cobalt-doped manganese phosphate monohydrate, and the large particles of about 2000 nm are iron oxide. The XRD and SEM images of the final product obtained in step 3 are shown in Figures 29 and 30, respectively. As can be seen, the final product is a mixture of cobalt-doped manganese phosphate and iron oxide with low crystallinity. The particle size distribution of the final product is also not uniform, ranging mainly from 50 to 2000 nm. There are many pores between the small particles, but the large particles have a relatively high density. Comparative Example 5

[0155] In this comparative example, a comparative phosphate material is provided, the preparation process of which is basically the same as that of Example 8, except that cobalt chloride hexahydrate is not added in step 1), and the preparation process is specifically as follows:

[0156] 1) A concentrated phosphoric acid solution and deionized water were added in a glass beaker in this order and stirred uniformly. Then, a 35% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.85 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 630 mL of the phosphoric acid aqueous solution. 0.60 Fe 0.40 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm) was poured into the mixture and mechanically stirred for 12 hours to obtain a reaction mixture.

[0157] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (ferric manganese phosphate monohydrate).

[0158] 3) Ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain reddish-brown powder ferromanganese phosphate.

[0159] The dark green powder obtained in step 2) was subjected to XRD and SEM testing and analysis, which showed that the crystalline phase of the material was MnPO4·H2O with a monoclinic phase structure and a particle size of 20 nm.

[0160] The reddish-brown powder obtained in step 3) was subjected to XRD and SEM testing and analysis, and the results showed that the crystalline phase of the material still maintained a monoclinic phase structure, with a particle size of 40 nm. The ferromanganese phosphate material had a mesoporous structure, with pore sizes mainly distributed between 3 and 5 nm, and a specific surface area of ​​15.0 m 2 / g. Example 14

[0161] In this example, the chemical formula is Mn 0.6 Fe 0.39 Zn 0.001 Cu 0.0005 Mg 0.005 Mo 0.003 Ti 0.0005 A nanoporous doped ferromanganese phosphate (PO4) is provided, the preparation process of which is as follows:

[0162] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.93 g of micron-level manganese iron oxide (molecular formula (Mn) 0.61 Fe 0.39 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.081 g of zinc oxide, 0.040 g of copper oxide, 0.20 g of magnesium oxide, 0.432 g of molybdenum oxide, and 0.040 g of titanium dioxide were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0163] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0164] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0165] The XRD and SEM images of manganese iron oxide are shown in Figures 35, 36-37, respectively, and as can be seen from these, manganese iron oxide has a crystalline structure. The XRD and SEM images of the doped manganese ferric phosphate monohydrate obtained in step 2 are shown in Figures 38, 39-40, respectively, and as can be seen from these, its crystalline phase is MnPO4·H2O with a monoclinic phase structure. As measured by a scanning electron microscope (SEM) test method, the particle size of the doped manganese ferric phosphate monohydrate is 25 nm. The doped manganese ferric phosphate monohydrate obtained in step 3) The XRD and SEM images of the ferromanganese are shown in Figures 41 and 42, respectively. As can be seen from these, the doped ferromanganese phosphate has a certain degree of crystallinity, and a large amount of porous structure is distributed between the particles. As can be seen from the XRD test, the crystalline phase still maintains a monoclinic phase structure. The measurement result of the scanning electron microscope (SEM) test method shows that the particle size of the doped ferromanganese phosphate is 35 nm. At the same time, the adsorption and desorption test and analysis of the doped ferromanganese phosphate were carried out using a specific surface area and aperture tester. As can be seen from Figures 48 and 49, the doped ferromanganese phosphate material has a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area is 15.1 m 2 / g. Example 15

[0166] In this example, the chemical formula is Mn 0.7 Fe 0.293 Mg 0.0015 V 0.001 Ti 0.0005 Cr 0.001Mo 0.003 A nanoporous doped ferromanganese phosphate (PO4) is provided, the preparation process of which is as follows:

[0167] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P was 1:1.5, which is the sum of Mn and Fe. 114.81 g of micron-level manganese iron oxide (molecular formula (Mn) 0.70 Fe 0.30 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.060 g of magnesium oxide, 0.117 g of ammonium metavanadate, 0.399 g of titanium dioxide, 0.152 g of chromium oxide, and 0.432 g of molybdenum oxide were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0168] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0169] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0170] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 35 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 14.8 m 2 / g. Example 16

[0171] In this example, the chemical formula is Mn 0.7 Fe 0.29 Nb 0.003 B 0.003 Co 0.001 V 0.002 Al 0.001 A nanoporous doped ferromanganese phosphate (PO4) is provided, the preparation process of which is as follows:

[0172] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 30% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.80 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 735 mL of the phosphoric acid aqueous solution. 0.71 Fe 0.29 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 1.614 g of niobium oxalate, 0.104 g of boron oxide, 0.177 g of cobalt acetate, 0.234 g of ammonium metavanadate, and 0.051 g of aluminum oxide were added and mechanically stirred for 12 hours to obtain the reaction mixture.

[0173] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0174] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0175] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 20 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 30 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 3 and 5 nm, and its specific surface area was 16.5 m 2 / g. Example 17

[0176] In this example, the chemical formula is Mn 0.8 Fe 0.19 Co 0.005 V 0.001 Ni 0.0005 B 0.003 Nb 0.0005 A nanoporous high-entropy doped ferromanganese phosphate (PO4) is provided, and its preparation process is as follows:

[0177] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 30% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was set to 1:1.5, which is the sum of Mn and Fe. 114.66 g of micron-level manganese iron oxide (molecular formula (Mn)) was added to 735 mL of the phosphoric acid aqueous solution. 0.81 Fe 0.19 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.885 g of cobalt acetate, 0.117 g of ammonium metavanadate, 0.088 g of nickel acetate, 0.186 g of boric acid, and 0.269 g of niobium oxalate were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0178] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0179] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0180] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 20 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 30 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 5 nm, and its specific surface area was 16.8 m 2 / g. Example 18

[0181] In this example, the chemical formula is Mn 0.5 Fe 0.49 Co 0.0025 Ga 0.0005 B 0.003 Al 0.002 Sr 0.002 A nanoporous doped ferromanganese phosphate (PO4) is provided, the preparation process of which is as follows:

[0182] 1) Add concentrated phosphoric acid solution and deionized water in a glass beaker in that order and stir evenly. The phosphoric acid solution was prepared with a mass concentration of 25%, and the molar ratio of P element was 1:1.5, based on the total of Mn and Fe. 115.07 g of micron-level manganese iron oxide (molecular formula (Mn) 0.51 Fe 0.49 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.325 g of cobalt chloride, 0.088 g of gallium chloride, 0.186 g of boric acid, 0.102 g of chromium oxide, and 0.317 g of strontium chloride were added and mechanically stirred for 12 hours to obtain the reaction mixture.

[0183] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0184] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0185] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 35 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 14.5 m 2 / g. Example 19

[0186] In this example, the chemical formula is Mn 0.65 Fe 0.34 Mo 0.003 Co 0.003 Ni 0.002 V 0.0015 Ca 0.0005 A nanoporous doped ferromanganese phosphate (PO4) is provided, the preparation process of which is as follows:

[0187] 1) A concentrated phosphoric acid solution and deionized water were added in that order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.87 g of micron-level manganese iron oxide (molecular formula (Mn) 0.66 Fe 0.34)3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.432 g of molybdenum oxide, 0.389 g of cobalt chloride, 0.259 g of nickel chloride, 0.4 g of vanadium oxalate, and 0.028 g of calcium oxide were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0188] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0189] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0190] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 35 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 14.7 m 2 / g. Comparative Example 6

[0191] In this comparative example, a comparative phosphate material is provided, and the manufacturing process thereof is basically the same as that of Example 14, specifically as follows:

[0192] 1) Concentrated phosphoric acid solution and deionized water are added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration aqueous phosphoric acid solution is prepared, with the total of Mn and Fe, and the P element molar ratio is 1:1.5. 48.15 g of manganese (III) oxide, 31.14 g of a mixture of iron (III) oxide (particle sizes of manganese oxide and iron oxide are both 7 μm), 0.081 g of zinc oxide, 0.040 g of copper oxide, 0.20 g of magnesium oxide, 0.432 g of molybdenum oxide, and 0.040 g of titanium dioxide are added to 882 mL of the above aqueous phosphoric acid solution, and the mixture is mechanically stirred for 12 hours to obtain a reaction mixture.

[0193] 2) Pour the reaction mixture into a sand mill and sand for 1 hour to obtain a dark brown slurry, filter and wash the slurry to obtain particles, and then dry the particles at 100°C to obtain a dark brown product.

[0194] 3) The product of step 2) is sintered in a muffle furnace at 400°C for 2 hours to obtain a dark brown final product.

[0195] The XRD and SEM images of the product obtained in step 2 are shown in Figures 43, 44 and 45, respectively. As can be seen from these, the product is zinc copper magnesium molybdenum titanium doped manganese phosphate monohydrate (Mn 0.9839 Zn 0.0016 Cu 0.0008 Mg 0.0081 Mo 0.0048 Ti 0.0008 The final product is a mixture of zinc copper magnesium molybdenum titanium doped manganese phosphate monohydrate (Mn PO4·H2O) and iron oxide, and the particle size distribution of the product is not uniform, ranging from 50 to 2000 nm. The small particles of about 50 nm are zinc copper magnesium molybdenum titanium doped manganese phosphate monohydrate, and the large particles of about 2000 nm are iron oxide. The XRD and SEM images of the final product obtained in step 3 are shown in Figures 46 and 47, respectively. As can be seen from these, the final product is a zinc copper magnesium molybdenum titanium doped manganese phosphate (Mn 0.9839 Zn 0.0016 Cu 0.0008 Mg 0.0081Mo 0.0048 Ti 0.0008 ) It is a mixture of PO4 and iron oxide, and the particle size distribution of the final product is not uniform, but is mainly distributed between 50 and 2000 nm. There are many pore structures between the small particles, but the large particles have a relatively high density. Comparative Example 7

[0196] In this comparative example, a comparative phosphate material is provided, the manufacturing process of which is basically the same as that of Example 14, except that in step 1), only compounds of four doping elements are added, and the manufacturing process is specifically as follows:

[0197] 1) A concentrated phosphoric acid solution and deionized water were added in this order to a glass beaker and stirred uniformly. Then, a 25% mass concentration phosphoric acid aqueous solution was prepared. The molar ratio of P element was 1:1.5, which is the sum of Mn and Fe. 114.93 g of micron-level manganese iron oxide (molecular formula (Mn) 0.61 Fe 0.39 )3O4 (purchased from Sichuan Qingyuan New Materials Co., Ltd., average particle size 7 μm), 0.081 g of zinc oxide, 0.040 g of copper oxide, 0.20 g of magnesium oxide, and 0.040 g of titanium dioxide were added and mechanically stirred for 12 hours to obtain a reaction mixture.

[0198] 2) The reaction mixture is poured into a sand mill and sanded for 1 hour to obtain a dark green slurry, which is filtered and washed to obtain particles, which are then dried at 100°C to obtain a dark green powder (doped ferric manganese phosphate monohydrate).

[0199] 3) The doped ferric manganese phosphate monohydrate is sintered in a muffle furnace at 400°C for 2 hours to obtain a reddish-brown powder.

[0200] After testing and analysis, it was found that the obtained doped manganese ferric phosphate monohydrate was MnPO4·H2O with a monoclinic phase structure, with a particle size of 25 nm. After heat treatment, the doped ferromanganese phosphate had a certain degree of crystallinity, and the crystalline phase still maintained a monoclinic phase structure. A large amount of porous structure was distributed between the particles, with a particle size of 35 nm. The doped ferromanganese phosphate material had a mesoporous structure, with the pore size mainly distributed between 4 and 6 nm, and its specific surface area was 15 m 2 / g. Application example 1

[0201] The ferromanganese phosphate or doped ferromanganese phosphate obtained in Examples 1 to 19, Comparative Examples 1 to 2, and Comparative Examples 4 to 7 was used to produce lithium ferromanganese phosphate, and the specific procedure is as follows.

[0202] 1) 113 g of lithium carbonate, 450.9 g of ferromanganese phosphate (Mn) according to the elemental molar ratio of Li:(Mn+Fe):P of 1.02:1:1 0.6 Fe 0.4 PO4), 68.3g of glucose, and other raw materials are weighed out.

[0203] 2) Pour 2.5 kg of water and the measured amount of glucose into a sand mill and mechanically stir for 10 minutes until the glucose is completely dissolved.

[0204] 3) Pour the measured amounts of ferromanganese phosphate and lithium carbonate into the sand mill and perform sanding dispersion for 2 hours.

[0205] 4) The slurry obtained by the sanding dispersion is spray-dried to obtain a precursor powder of lithium ferromanganese phosphate (LMFP) / C.

[0206] 5) The LMFP / C precursor powder is first pre-baked at 350°C for 2 hours in an inert atmosphere, and then secondary sintered at 600°C for 10 hours to finally obtain the LMFP / C cathode material.

[0207] The LMFP / C cathode material, carbon nanotubes, carbon black, polyvinylidene fluoride, and N-methylpyrrolidone were mixed together to form a cathode slurry. The mass ratio of the LMFP / C cathode material, carbon nanotubes, carbon black, and polyvinylidene fluoride was 91.5:1.5:1.0:6. The cathode slurry was applied to aluminum foil, followed by vacuum baking and punching to produce LMFP / C cathode pieces. Button batteries were assembled using the LMFP / C cathode and lithium anode pieces, and a 1 mol / L LiPF6 solution of ethylene carbonate (EC), dimethyl carbonate (DMC), and methyl ethyl carbonate (EMC) as the electrolyte. Charge-discharge tests (2.5 V to 4.3 V) demonstrated the electrical performance of the lithium ferromanganese phosphate. The results are shown in Table 1 below, the results of Example 1 are also shown in FIGS. 19-20, the results of Example 8 are also shown in FIGS. 33-34, and the results of Example 14 are also shown in FIGS.

[0208] [Table 1]

[0209] The above examples are merely for the purpose of illustrating the technical ideas and features of the present invention, and are intended to enable those skilled in the art to understand and practice the contents of the present invention, but are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made substantially in accordance with the idea of ​​the present invention shall be included in the scope of protection of the present invention.

Claims

1. The chemical formula is Mn １－ｘ Fe ｘ P.O. ４ ferromanganese phosphate, 0.01≦x≦0.99, and the ferromanganese phosphate has a particle size of 50 nm or less and a porous structure.

1. Ferromanganese phosphate characterized by:

2. The particle size of the ferromanganese phosphate is 40 nm or less, more preferably 5 to 40 nm, and even more preferably 10 to 30 nm.

2. The ferromanganese phosphate of claim 1.

3. The ferromanganese phosphate has a specific surface area of ​​10 to 30 m ２ / g, and a pore size of 2 to 10 nm. Preferably, the ferromanganese phosphate has a specific surface area of ​​12 to 18 m ２ / g, pore size is 3-5 nm 2. The ferromanganese phosphate of claim 1.

4. 0.1≦x≦0.9, preferably 0.2≦x≦0.5 2. The ferromanganese phosphate of claim 1.

5. The ferromanganese phosphate is in monoclinic crystal form.

2. The ferromanganese phosphate of claim 1.

6. A phosphate-based material, The chemical formula of the phosphate-based material is Mn １－ａ－ｂ Fe ａ M ｂ P.O. ４ M is one or a combination of one or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium, and 0.01≦a≦0.98, 10 －４ ≦b≦10 －２ The phosphate-based material has a particle size of 50 nm or less and a porous structure. A phosphate-based material characterized by:

7. The particle size of the phosphate-based material is 40 nm or less, more preferably 5 to 40 nm, and even more preferably 10 to 30 nm.

7. The phosphate-based material according to claim 6.

8. The phosphate-based material has a specific surface area of ​​10 to 30 m ２ / g, pore size is 2 to 10 nm, and preferably, the phosphate-based material has a specific surface area of ​​12 to 18 m ２ / g, pore size is 3-5 nm 7. The phosphate-based material according to claim 6.

9. 0.2≦a≦0.5, 10 －３ ≦b≦10 －２ and / or the phosphate-based material is in monoclinic crystalline form.

7. The phosphate-based material according to claim 6.

10. The M is cobalt, or the M is magnesium and boron, or the M is molybdenum, niobium and boron, or the M is cobalt, vanadium, nickel and boron, or the M is magnesium, or the M is vanadium and titanium.

7. The phosphate-based material according to claim 6.

11. The chemical formula of the phosphate-based material is Mn １－ａ－ｂ Fe ａ Co ｂ P.O. ４ and or Mn １－ａ－ｂ Fe ａ Mg ｂ１ B ｂ２ P.O. ４ and b1+b2=b; or Mn １－ａ－ｂ Fe ａ Mo ｂ１ Nb ｂ２ B ｂ３ P.O. ４ and b1+b2+b3=b; or Mn １－ａ－ｂ Fe ａ Co ｂ１ V ｂ２ Ni ｂ３ B ｂ４ P.O. ４ and b1+b2+b3+b4=b; or Mn １－ａ－ｂ Fe ａ Mg ｂ P.O. ４ and or Mn １－ａ－ｂ Fe ａ V ｂ１ Ti ｂ２ P.O. ４ and b1+b2=b; 10 －４ ≦b1≦10 －２ , 10 －４ ≦b2≦10 －２ , 10 －４ ≦b3≦10 －２ , 10 －４ ≦b4≦10 －２ is 7. The phosphate-based material according to claim 6.

12. The chemical formula of the phosphate-based material is Mn ０．６ Fe ０．３９５ Co ０．００５ P.O. ４ or Mn ０．６５ Fe ０．３４４ Mg ０．００５ B ０．００１ P.O. ４ or Mn ０．７ Fe ０．２９３ Mo ０．００３ Nb ０．００３ B ０．００１ P.O. ４ or Mn ０．８ Fe ０．１９ Co ０．００５ V ０．００１ Ni ０．００１ B ０．００３ P.O. ４ or Mn ０．５ Fe ０．４９５ Mg ０．００５ P.O. ４ or Mn ０．６５ Fe ０．３４ V ０．００５ Ti ０．００５ P.O. ４ is 7. The phosphate-based material according to claim 6.

13. The M is five or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium.

7. The phosphate-based material according to claim 6.

14. The chemical formula of the phosphate-based material is Mn １－ａ－ｂ Fe ａ Mg ｂ１ V ｂ２ Ti ｂ３ Cr ｂ４ Co ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Zn ｂ１ Cu ｂ２ Mg ｂ３ Co ｂ４ Ti ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Zn ｂ１ Cu ｂ２ Mg ｂ３ Mo ｂ４ Ti ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Mg ｂ１ V ｂ２ Ti ｂ３ Cr ｂ４ Mo ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Nb ｂ１ B ｂ２ Co ｂ３ V ｂ４ Al ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Co ｂ１ V ｂ２ Ni ｂ３ B ｂ４ Nb ｂ５ P.O. ４ , Mn １－ａ－ｂ Fe ａ Co ｂ１ Ga ｂ２ B ｂ３ Al ｂ４ Sr ｂ５ P.O. ４ or Mn １－ａ－ｂ Fe ａ Mo ｂ１ Co ｂ２ Ni ｂ３ V ｂ４ Ca ｂ５ P.O. ４ b1+b2+b3+b4+b5=b, and the range of b1 to b5 is 10 －４ ≦b1≦10 －２ , 10 －４ ≦b2≦10 －２ , 10 －４ ≦b3≦10 －２ , 10 －４ ≦b4≦10 －２ , 10 －４ ≦b5≦10 －２ is 7. The phosphate-based material according to claim 6.

15. The chemical formula of the phosphate-based material is Mn ０．７ Fe ０．２９３ Mg ０．０１５ V ０．００１ Ti ０．０００５ Cr ０．００１ Co ０．００３ P.O. ４ , Mn ０．６ Fe ０．３９５ Zn ０．００１ Cu ０．０００５ Mg ０．００１ Co ０．００２ Ti ０．０００５ P.O. ４ , Mn ０．６ Fe ０．３９ Zn ０．００１ Cu ０．０００５ Mg ０．００５ Mo ０．００３ Ti ０．０００５ P.O. ４ , Mn ０．７ Fe ０．２９３ Mg ０．００１５ V ０．００１ Ti ０．０００５ Cr ０．００１ Mo ０．００３ P.O. ４ , Mn ０．７ Fe ０．２９ Nb ０．００３ B ０．００３ Co ０．００１ V ０．００２ Al ０．００１ P.O. ４ , Mn ０．８ Fe ０．１９ Co ０．００５ V ０．００１ Ni ０．０００５ B ０．００３ Nb ０．０００５ P.O. ４ , Mn ０．５ Fe ０．４９ Co ０．００２５ Ga ０．０００５ B ０．００３ Al ０．００２ Sr ０．００２ P.O. ４ or Mn ０．６５ Fe ０．３４ Mo ０．００３ Co ０．００３ Ni ０．００２ V ０．００１５ Ca ０．０００５ P.O. ４ is 7. The phosphate-based material according to claim 6.

16. A method for producing a phosphate-based material, comprising: The manufacturing method includes: 1) mixing manganese iron oxide and an optional compound of element M with phosphoric acid to obtain a reaction mixture; 2) grinding the reaction mixture to react with the reaction mixture to produce phosphate, and obtaining a slurry containing the phosphate, wherein the particle size of the phosphate in the slurry is 100 nm or less; 3) separating the slurry to obtain phosphate particles; 4) drying and sintering the phosphate particles to obtain the phosphate-based material, wherein M is one or a combination of two or more selected from magnesium, titanium, vanadium, chromium, cobalt, nickel, zinc, gallium, aluminum, zirconium, niobium, molybdenum, tin, antimony, calcium, barium, strontium, boron, ruthenium, silicon, tellurium, niobium, copper, and lithium. A method for producing a phosphate-based material, comprising:

17. The particle size of the manganese iron oxide is 1 to 20 μm, preferably 2 to 7 μm, and / or the phosphoric acid is present in the form of an aqueous phosphoric acid solution, and the mass concentration of the aqueous phosphoric acid solution is 10% to 70%, preferably 20% to 40%.

17. The method for producing a phosphate-based material according to claim 16.

18. In step 1), the mixing is carried out with mechanical stirring at a temperature of 20 to 40°C, and / or In step 2), the grinding is carried out in a sand mill, and the grinding temperature is 20 to 40°C; and / or In step 4), the drying temperature is 100 to 120°C, and / or In step 4), the sintering temperature is 300-400°C, and / or The step 3) includes filtering and washing the phosphate slurry.

17. The method for producing a phosphate-based material according to claim 16.

19. The step 4) includes a step of drying the phosphate particles to obtain ferrous manganese phosphate monohydrate crystals or doped ferrous manganese phosphate monohydrate crystals having a particle size of 100 nm or less, and further sintering the ferrous manganese phosphate monohydrate crystals or doped ferrous manganese phosphate monohydrate crystals to obtain the phosphate-based material.

17. The method for producing a phosphate-based material according to claim 16.

20. The ratio of the total amount of the manganese iron oxide and the compound of element M to the amount of the phosphoric acid is 1:1 to 2.

17. The method for producing a phosphate-based material according to claim 16.

21. The manufacturing method further includes, before step 1), a step of pre-dispersing the manganese iron oxide in an aqueous dispersant solution.

17. The method for producing a phosphate-based material according to claim 16.

22. The dispersant is one or a combination of polyvinylpyrrolidone, polyethylene glycol, and TC130 dispersant, and / or the mass concentration of the dispersant aqueous solution is 0.01% to 5%.

22. The method for producing a phosphate-based material according to claim 21.

23. In the production method, before the step 1), phosphorus pentoxide is reacted with water to produce phosphoric acid. Further comprising the steps 17. The method for producing a phosphate-based material according to claim 16.

24. The compound of element M is one or a combination of a plurality of compounds selected from a magnesium compound, a titanium compound, a vanadium compound, a cobalt compound, a nickel compound, a zinc compound, a gallium compound, an aluminum compound, a zirconium compound, a niobium compound, a molybdenum compound, a tin compound, an antimony compound, a calcium compound, a barium compound, a strontium compound, a boron compound, a ruthenium compound, a silicon compound, a tellurium compound, a niobium compound, a copper compound, and a lithium compound.

24. The method for producing a phosphate-based material according to any one of claims 16 to 23.

25. The compound of element M is one or a combination of a plurality of compounds selected from oxides, carbonates, oxalates, nitrates, sulfates, chlorides, and organic acid salts of element M.

24. The method for producing a phosphate-based material according to any one of claims 16 to 23.

26. The compound of element M is cobalt chloride, or a combination of magnesium oxide and boric acid, or a combination of molybdenum trioxide, niobium oxalate and boric acid, or a combination of cobalt acetate, ammonium metavanadate, nickel sulfate and boric acid, or magnesium acetate, or a combination of vanadyl oxalate and titanium chloride.

24. The method for producing a phosphate-based material according to any one of claims 16 to 23.

27. 24. The method for producing a phosphate-based material according to any one of claims 16 to 23, wherein the compound of element M is a combination of five or more selected from a compound of magnesium, a compound of titanium, a compound of vanadium, a compound of cobalt, a compound of nickel, a compound of zinc, a compound of gallium, a compound of aluminum, a compound of zirconium, a compound of niobium, a compound of molybdenum, a compound of tin, a compound of antimony, a compound of calcium, a compound of barium, a compound of strontium, a compound of boron, a compound of ruthenium, a compound of silicon, a compound of tellurium, a compound of niobium, a compound of copper, and a compound of lithium.

28. The compound of element M is a combination of magnesium acetate, ammonium metavanadate, titanium oxide, cadmium oxide, and cobalt sulfate; a combination of zinc sulfate, copper oxalate, cobalt acetate, magnesium nitrate, cobalt oxide, and n-butyl titanate; a combination of zinc oxide, copper oxide, magnesium oxide, molybdenum oxide, and titanium dioxide; a combination of magnesium oxide, ammonium metavanadate, titanium dioxide, chromium oxide, and molybdenum oxide; a combination of niobium oxalate, boron oxide, cobalt acetate, ammonium metavanadate, and aluminum oxide; a combination of cobalt acetate, ammonium metavanadate, nickel acetate, boric acid, and niobium oxalate; a combination of cobalt chloride, gallium chloride, boric acid, chromium oxide, and strontium chloride; or a combination of molybdenum oxide, cobalt chloride, nickel chloride, vanadium oxalate, and calcium oxide.

24. The method for producing a phosphate-based material according to any one of claims 16 to 23.

29. Ferromanganese phosphate according to any one of claims 1 to 5 or any one of claims 6 to 15 30. Use of the phosphate-based material according to any one of claims 16 to 29 or a phosphate-based material obtained by the method for producing a phosphate-based material according to any one of claims 16 to 29 in the production of a battery positive electrode material.

30. The manganese iron phosphate-based battery positive electrode material is obtained by subjecting raw materials containing the ferromanganese phosphate according to any one of claims 1 to 5, the phosphate-based material according to any one of claims 6 to 15, or the phosphate-based material obtained by the method for producing a phosphate-based material according to any one of claims 16 to 28, a lithium source (based) compound, and an arbitrary organic carbon source to a high-temperature sintering reaction. A manganese iron phosphate-based battery positive electrode material characterized by:

31. The lithium source (based) compound is one or a combination of two or more selected from lithium carbonate, lithium hydroxide, lithium chloride, lithium sulfate, lithium nitrate, lithium dihydrogen phosphate, lithium dihydrogen phosphate, and lithium acetate.

31. The manganese iron phosphate battery cathode material of claim 30.

32. The organic carbon source is one or a combination of two or more selected from glucose, sucrose, fructose, citric acid, polyethylene glycol, polyvinylpyrrolidone, ethylenediaminetetraacetic acid, and ascorbic acid.

31. The manganese iron phosphate battery cathode material of claim 30.

33. 1. A sodium-ion battery comprising a positive electrode material, The positive electrode material comprises the manganese iron phosphate-based positive electrode material according to claim 30, 31 or 32. A sodium-ion battery characterized by:

34. The lithium ion battery has a discharge specific capacity of 145 mAh / g or more at 0.1C, a discharge specific capacity of 135 mAh / g or more at 1C, and a capacity retention rate of 92% or more after 200 charge / discharge cycles at 1C.

34. The lithium ion battery of claim 33.

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