CN107814564B - Low-cost carbon-coated titanium phosphate compound batch preparation method - Google Patents
Low-cost carbon-coated titanium phosphate compound batch preparation method Download PDFInfo
- Publication number
- CN107814564B CN107814564B CN201610821504.9A CN201610821504A CN107814564B CN 107814564 B CN107814564 B CN 107814564B CN 201610821504 A CN201610821504 A CN 201610821504A CN 107814564 B CN107814564 B CN 107814564B
- Authority
- CN
- China
- Prior art keywords
- carbon
- source
- phosphate compound
- powder
- titanium phosphate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/447—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on phosphates, e.g. hydroxyapatite
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/6261—Milling
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/62605—Treating the starting powders individually or as mixtures
- C04B35/62645—Thermal treatment of powders or mixtures thereof other than sintering
- C04B35/62655—Drying, e.g. freeze-drying, spray-drying, microwave or supercritical drying
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/628—Coating the powders or the macroscopic reinforcing agents
- C04B35/62802—Powder coating materials
- C04B35/62828—Non-oxide ceramics
- C04B35/62839—Carbon
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
- C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
- C04B35/638—Removal thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3201—Alkali metal oxides or oxide-forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3201—Alkali metal oxides or oxide-forming salts thereof
- C04B2235/3203—Lithium oxide or oxide-forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3232—Titanium oxides or titanates, e.g. rutile or anatase
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/658—Atmosphere during thermal treatment
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
- C04B2235/74—Physical characteristics
- C04B2235/78—Grain sizes and shapes, product microstructures, e.g. acicular grains, equiaxed grains, platelet-structures
- C04B2235/782—Grain size distributions
Abstract
The invention relates to a method for preparing low-cost carbon-coated titanium phosphate compound in batches, wherein the chemical formula of the titanium phosphate compound is MxTi2（PO4）3Wherein M is at least one of alkali metals, and x = 1-1.05, the method comprises: step 1) taking an alkali metal source, a phosphorus source, a titanium source and a carbon source in a stoichiometric ratio as raw materials, and performing wet ball milling to obtain slurry; step 2) obtaining carbon-coated titanium phosphate compound precursor mixed powder by using a centrifugal spray drying method for the slurry; and 3) sintering the precursor mixed powder by adopting a solid-phase synthesis method to obtain carbon-coated titanium phosphate compound powder. The method has simple process and low cost, and can be widely applied to large-scale production of the titanium phosphate compound.
Description
Technical Field
The invention relates to a method suitable for preparing carbon-coated titanium phosphate compound ceramic powder in batches, in particular to a method for preparing carbon-coated titanium phosphate compound ceramic powder by ball-milling and mixing a carbon-containing precursor and precursors of various phase components, spray drying and granulating and adopting a high-temperature solid-phase synthesis reaction method, belonging to the field of ion-conductive ceramic materials.
background
The titanium phosphate compound is a typical NASICON structure, which has a large tunnel size to allow free migration of alkali metal ions. It is a fast ion conductor, has high ion conductivity, smaller electron conductivity and excellent thermal stability, and is an important alkali metal ion battery electrode material. With NaTi2(PO4)3for example, at 1mol/LNa2SO4In solution, NaTi2(PO4)3a pair of quite symmetrical oxidation reduction peaks exist at-0.82V (vs. Ag/AgCl), which indicates that sodium ions can perform reversible intercalation and deintercalation reaction at-0.82V. The reaction potential interval is slightly higher than the hydrogen evolution potential of water, and the more negative anode potential not only makes full use of the hydrogen evolution potential window of water and is beneficial to improving the working voltage of the battery, but also ensures that no hydrogen evolution side reaction occurs in the normal sodium intercalation and deintercalation reaction process. The charging and discharging curves show that, NaTi2(PO4)3A stable charge-discharge platform is arranged at-0.82V, the reversible capacity is 120mAh/g, and the reversible capacity is equivalent to the de-intercalation capacity of two sodium ions. Benefiting from NaTi2(PO4)3The fast ion conductor structure of the material can still release 70 percent of reversible specific capacity when the fast ion conductor structure is charged and discharged under the high multiplying power of 100C, so the fast ion conductor structure can be used as a high-power negative electrode material. MxTi2(PO4)3After carbon coating treatment, the electronic conductivity of the material is improved, the utilization rate of active substances is obviously improved, and the occurrence of side reactions can be effectively prevented due to the fact that direct contact between electrolyte and the surface of the material is avoided, so that the circulation stability of the material is greatly improved.
At present, methods for preparing carbon-coated titanium phosphate compounds mainly include microwave heating synthesis, hydrothermal method, sol-gel method, etc. [ J.Mater.Chem.A,2015,3,12089-12096 ]. Compared with the traditional solid-phase synthesis method, the method has the advantages that the prepared powder has higher purity and excellent performance, but the production process is complex, more equipment is provided, the large-scale production is difficult to realize, and particularly, the carbon coating needs to be carried out for multiple times of heat treatment and grinding, the cost is higher, and the requirement of reducing the cost of the battery cannot be met. The traditional solid phase synthesis method also has the defects of more side reactions caused by uneven powder mixing, impure products and the like.
Disclosure of Invention
in view of the above problems, the present invention is directed to a method for preparing a carbon-coated titanium phosphate compound having high purity, which is simple in process, low in cost, and capable of mass production.
The invention provides a method for preparing a carbon-coated titanium phosphate compound, wherein the chemical formula of the titanium phosphate compound is MxTi2(PO4)3Wherein M is at least one of alkali metals, and x is 1-1.05, the method comprises the following steps:
Step 1) taking an alkali metal source, a phosphorus source, a titanium source and a carbon source (preferably an inorganic carbon source) in a stoichiometric ratio as raw materials, and performing wet ball milling to obtain slurry;
Step 2) obtaining carbon-coated titanium phosphate compound precursor mixed powder by using a centrifugal spray drying method for the slurry;
And 3) sintering the precursor mixed powder by adopting a solid-phase synthesis method to obtain carbon-coated titanium phosphate compound powder.
The method is different from the traditional solid-phase synthesis method, adopts a mode of ball milling to prepare slurry and spray drying granulation, ensures that the obtained powder particles are spherical, ensures that the precursor of the titanium phosphate compound is uniformly mixed and the titanium phosphate compound is easily coated by carbon, and prepares the carbon-coated titanium phosphate compound in batch by performing high-temperature solid-phase reaction on the obtained powder, and particularly can avoid the problems of nonuniform high-temperature reaction components and other crystalline phase impurities in powder sintering in the traditional solid-phase reaction due to nonuniform mixing. The product obtained by the method has high purity, can well improve the conductivity of the material and greatly improve the electrochemical performance of the material, has simple process and low cost, and can be widely applied to large-scale production of the titanium phosphate compound.
Preferably, in the step 1), the solvent for wet ball milling is water or a mixed solvent of water and ethanol, and the content of ethanol in the mixed solvent is 0-10 wt.%. The invention selects water (preferably deionized water) which is cheap and easy to obtain and is harmless to the environment as a main solvent, can reduce the cost and is environment-friendly.
Preferably, in the step 1), the content of the carbon source is 0-20 wt.%. Preferably, the carbon source is pretreated with an organic solvent containing hydroxyl functional groups prior to addition to the ball mill to enhance wettability. According to the invention, the precursor of the titanium phosphate compound can be mixed more uniformly, and the titanium phosphate compound can be coated by carbon more easily.
Preferably, step 1) comprises: mixing an alkali metal source, a titanium source and a phosphorus source according to a molar ratio of (1-1.05) to 2:3, pouring the mixed raw materials into a ball milling barrel, adding deionized water according to 10-50 wt.% of solid content, and carrying out ball milling for 1-5 hours at a rotating speed of 50-300 r/min to obtain first slurry; and adding a carbon source into the obtained first slurry, and mixing and ball-milling for 1-5 hours at a rotating speed of 50-300 r/min.
According to the invention, the slurry with certain viscosity and particle size can be obtained by a step-by-step ball milling method, compared with one-step ball milling, the mixing is more uniform, and the particle size distribution of the finally obtained slurry powder can be controlled by the step-by-step ball milling because the initial particle size of each powder is different.
Preferably, in step 1), a defoaming agent and/or a dispersing agent is also added. Preferably, the defoaming agent is higher alcohol, the addition amount of the higher alcohol is 0.5-5 wt% of the powder, and the addition amount of the dispersing agent is 0.5-5 wt% of the powder. Preferably, the dispersant is any one or more selected from polyacrylic acid, sodium hexametaphosphate, polyethylene glycol, fish oil and castor oil.
Preferably, in step 1), the alkali metal source is any one of carbonate, hydroxide, oxalate, acetate, dihydrogen phosphate and nitrate of alkali metal;
The titanium source is any one of titanium dioxide, metatitanic acid, titanic acid and titanium tetrachloride;
the phosphorus source is any one of lithium dihydrogen phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and ammonium phosphate;
The carbon source is any one or more of graphite, activated carbon, acetylene black, graphene and the like.
Preferably, in the step 1), the solid content of the obtained slurry is 20-60 wt.%.
preferably, in the step 2), centrifugal spray drying equipment is used, the air inlet temperature is controlled to be 100-240 ℃, preferably 200-240 ℃, the air outlet temperature is controlled to be 80-110 ℃, preferably 100-110 ℃, and the centrifugal speed is 10000-20000 rpm, preferably 12000-15000 rpm. By controlling the process parameters of the centrifugal spray drying apparatus as described above, spherical particles having a more uniform size distribution can be obtained.
Preferably, in the step 3), the sintering is performed at 600-1000 ℃ for 1-24 hours under a protective atmosphere of nitrogen or argon. According to the present invention, carbon-coated titanium phosphate compound ceramic powder having high crystal phase purity can be obtained.
Preferably, in step 3), before the temperature is raised to the sintering temperature, the deamination reaction is performed at a constant temperature of 200-400 ℃ (e.g., 200-350 ℃ or 250-400 ℃) for 1-3 hours.
the invention adopts ball milling mixing and spray drying method to obtain carbon-coated titanium phosphate compound ceramic powder through high-temperature solid-phase reaction. Compared with the prior art, the invention has the following advantages and beneficial effects:
1. By spray drying, the carbon coating of active materials such as graphite and the like can be realized, the conductivity of the material is improved, and the electrochemical performance of the material is greatly improved;
2. through spray drying, particles with uniform size distribution can be obtained, and the sintering performance of the powder material is favorably improved;
3. The carbon-coated alkali metal ion electrode material with the NASICON structure synthesized by the solid phase method has better electrochemical performance, simple synthesis process, easy control and low price, and can be applied to energy storage equipment, a backup power supply, a reserve power supply and the like;
4. The method has the advantages of short synthesis period, cheap raw materials, simple process, easy control, obvious practical value and good application prospect.
drawings
FIG. 1 is a flow chart of mass production of a titanium phosphate compound according to an embodiment of the present invention;
FIG. 2 is an SEM image of the sintered powder of an embodiment of the invention;
FIG. 3 is a diagram illustrating a particle size distribution of sintered powder according to an embodiment of the present invention;
FIG. 4 is a powder XRD pattern after sintering in accordance with one embodiment of the present invention.
Detailed Description
The present invention is further described below in conjunction with the following embodiments and the accompanying drawings, it being understood that the drawings and the following embodiments are illustrative of the invention only and are not limiting.
The invention provides a carbon-coated titanium phosphate compound MxTi2(PO4)3(M ═ Na, Li, K, etc., where x ═ 1 to 1.05) low cost mass production methods. The prepared powder is made into a sphere by ball milling dispersion and centrifugal spray drying granulation, so that the precursor of the titanium phosphate compound is uniformly mixed and easily coated by carbon, and the obtained powder is subjected to a high-temperature solid-phase reaction method to prepare the carbon-coated titanium phosphate compound in batches. Fig. 1 shows a flow chart for mass production of a titanium phosphate compound according to an embodiment of the present invention. Hereinafter, the method for producing the titanium phosphate compound will be specifically described with reference to FIG. 1.
firstly, ball milling and mixing are carried out. In the present invention, the raw materials may comprise an alkali metal source, a phosphorus source, a titanium source and a carbon source. The raw materials can adopt powder. The invention has no over-high requirement on the purity of the raw material powder, and can use industrial raw materials. The raw materials can be synthesized by the existing method or purchased commercially.
as the alkali metal source, any one or more of lithium carbonate (sodium, potassium), lithium hydroxide (sodium, potassium), lithium oxalate (sodium, potassium), lithium acetate (sodium, potassium), lithium dihydrogen phosphate (sodium, potassium) or lithium nitrate (sodium, potassium) is included, but not limited thereto.
As a phosphorus source, any one or more of lithium dihydrogen phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, or ammonium phosphate is included, but not limited thereto.
as a titanium source, any one or several of titanium dioxide, metatitanic acid, titanic acid, titanium tetrachloride are included, but not limited thereto. Wherein the titanium dioxide can be any one or more of rutile, anatase and brookite.
as the carbon source, an inorganic carbon source is preferred, including but not limited to any one or more of graphite, activated carbon, acetylene black, and graphene.
Alkali metal source, phosphorus source, titanium source according to the stoichiometric formula M of the titanium phosphate compoundxTi2(PO4)3(M ═ Na, Li, K, etc., wherein x ═ 1 to 1.05) in proportion.
The carbon source may be present in an amount of 0 to 50wt.%, preferably 10 to 20 wt.%. In addition, the carbon source may be pretreated with ethanol or other organic solvent containing hydroxyl functional groups prior to addition to the ball mill to enhance wettability.
Deionized water which is cheap and easy to obtain and is harmless to the environment can be selected as a main solvent during ball milling. A mixed solvent of water and ethanol may also be used. Wherein the ethanol content is preferably 0-20 wt.%.
A small amount of higher alcohol (preferably C7-C9 alcohol) can be added as defoaming agent during ball milling. In addition, a small amount of dispersing agent can be added, and the addition amount of the dispersing agent can be 0.5-5 wt% of the powder. The dispersing agent includes but is not limited to one or more of polyacrylic acid, sodium hexametaphosphate, polyethylene glycol, fish oil and castor oil.
In the invention, the ball milling and mixing can adopt a step-by-step ball milling method. In one example, the method comprises the following steps: a first ball-milling step of mixing an alkali metal source, a phosphorus source, a titanium source and a solvent and then performing ball-milling; and a second ball milling step of further ball milling by adding a carbon source. In the first ball milling step, the mass ratio of the total mass of the powder to the solvent and the grinding balls can be (10-50): (50-90): (10-30). The rotation speed can be 50-300 r/min, and the ball milling time can be 1-5 hours. In the second ball milling step, the rotation speed can be 50-300 r/min, and the ball milling time can be 1-5 hours.
The solid content of the slurry obtained by ball milling and mixing is controlled to be 0-60 wt.%, and preferably, is controlled to be 20-30 wt.%. The particle size of the slurry is 1-10 μm.
then, the slurry was granulated by a centrifugal spray dryer to obtain a carbon-coated titanium phosphate compound precursor mixed powder. Centrifugal spray drying equipment can be used, the air inlet temperature is controlled to be 100-240 ℃, the air outlet temperature is controlled to be 200-240 ℃, the air outlet temperature is controlled to be 80-110 ℃, the air outlet temperature is controlled to be 100-110 ℃, the centrifugal speed is 10000-20000 rpm, and the centrifugal speed is 10000-15000 rpm.
And further sintering the granulated powder at high temperature by using an atmosphere furnace by adopting a traditional solid-phase synthesis method to obtain carbon-coated titanium phosphate compound powder. The deamination reaction can be carried out at a medium-low temperature (for example, 250-400 ℃), and then the constant-temperature sintering is kept for 1-24 h (for example, 10h) at 650-1000 ℃ (preferably 650-950 ℃). During sintering, inert gas can be used as the protective gas of the sintering furnace, for example, the atmosphere can be one or more of argon and nitrogen.
The invention uses several specific raw materials to obtain slurry with certain viscosity and particle size by a step-by-step ball milling method. And (3) further carrying out spray drying treatment on the slurry to obtain precursor powder which is uniformly mixed and well dispersed, and carrying out solid-phase reaction under a specific sintering condition to synthesize the carbon-coated titanium phosphate compound powder. The invention has simple process, low cost, uniform ball milling and good powder dispersion degree. The powder particles obtained by adopting a centrifugal spray drying mode are spherical, so that the titanium phosphate compound is easily coated by carbon, and the problems that high-temperature reaction components are not uniform and other crystalline phase impurities appear in powder sintering due to nonuniform mixing in the traditional solid phase reaction can be particularly avoided. The method is suitable for mass production of the carbon-coated titanium phosphate compound. The key point of the invention is that the method is different from the traditional solid phase synthesis method, adopts a mode of ball milling slurry preparation and spray drying granulation to obtain powder particles in a spherical shape, so that the titanium phosphate compound is easy to be coated by carbon, successfully prepares carbon-coated titanium phosphate compound powder, adopts a high-temperature solid phase synthesis method, uses an atmosphere furnace, firstly carries out deamination reaction at medium and low temperature, and keeps for a period of time at a certain temperature to obtain carbon-coated titanium phosphate compound ceramic powder with high crystalline phase purity.
Fig. 2 and 3 show SEM images and particle size distribution diagrams of the carbon-coated titanium phosphate compound powder prepared according to one embodiment of the present invention, and it can be seen that the particle size is about 1 to 10 μm, the prepared powder is uniformly dispersed, and the carbon coating property is good. Fig. 4 shows an XRD pattern of the carbon-coated titanium phosphate compound powder prepared according to one embodiment of the present invention, and the result shows that the sintered ceramic powder has high crystal purity, no hetero-peak, and the content of the carbon-coated titanium phosphate compound measured by atomic absorption spectrometry is 95-99.9%, preferably 99.9%.
The present invention will be described in detail by way of examples. It is also to be understood that the following examples are illustrative of the present invention and are not to be construed as limiting the scope of the invention, and that certain insubstantial modifications and adaptations of the invention by those skilled in the art may be made in light of the above teachings. The specific process parameters and the like of the following examples are also only one example of suitable ranges, i.e., those skilled in the art can select the appropriate ranges through the description herein, and are not limited to the specific values exemplified below.
Example 1
Taking sodium carbonate, ammonium dihydrogen phosphate and titanium dioxide powder as raw materials, adding the sodium, titanium and phosphorus into a mixed solution of ethanol and water (1:10) according to a molar ratio of 1:2:3, wherein the mass ratio of the raw material powder to the mixed solution of the ethanol and the water is 30: 70. polyacrylic acid is selected as a dispersing agent, the addition amount of the dispersing agent is 1 wt% of the powder, and uniform slurry is obtained by ball milling for 2 hours at a high speed of 200 revolutions per minute through a coarse mill. Continuously adding 20wt.% of active substance graphite pretreated by ethanol), further performing ball milling at the rotating speed of 200 rpm for 2 hours, and then pouring out the slurry. And (3) adopting a spray drying method to the obtained slurry, setting the air inlet temperature to be 220 ℃, the air outlet temperature to be 110 ℃ and the centrifugal rotating speed to be 12000 r/m, and collecting the obtained spherical powder precursor. And putting the precursor into an inert gas filled sintering furnace, and sintering for 10 hours at the temperature of 750 ℃ in a nitrogen atmosphere to obtain the carbon-coated titanium phosphate compound ceramic powder. The SEM image, the particle size distribution diagram and the XRD image can be respectively seen in figures 2-4.
Example 2
Lithium carbonate, ammonium dihydrogen phosphate and titanium dioxide powder are used as raw materials, the content of lithium, titanium and phosphorus is added into a mixed solution of ethanol and water (1:10) according to the molar ratio of 1:2:3, and the mass ratio of the raw material powder to the mixed solution of the ethanol and the water is 30: 70. selecting sodium hexametaphosphate as a dispersing agent, wherein the addition amount of the dispersing agent is 1 wt% of the powder, and performing ball milling for 2 hours at a high speed of 200 revolutions per minute by a coarse mill to obtain uniform slurry. Continuously adding 20wt.% of active substance graphite pretreated by ethanol), further performing ball milling at the rotating speed of 200 rpm for 2 hours, and then pouring out the slurry. And (3) adopting a spray drying method to the obtained slurry, setting the air inlet temperature to be 220 ℃, the air outlet temperature to be 110 ℃, and the centrifugal rotating speed to be 15000 r/m, and collecting the obtained spherical powder precursor. And putting the precursor into an inert gas filled sintering furnace, and sintering for 10 hours at the temperature of 750 ℃ in a nitrogen atmosphere to obtain the carbon-coated titanium phosphate compound ceramic powder.
example 3
Taking sodium carbonate, ammonium dihydrogen phosphate and titanium dioxide powder as raw materials, adding potassium, titanium and phosphorus into a mixed solution of ethanol and water (1:10) according to a molar ratio of 1:2:3, wherein the mass ratio of the raw material powder to the mixed solution of the ethanol and the water is 20: 80. castor oil is selected as a dispersing agent, the addition amount of the dispersing agent is 1 wt% of the powder, and uniform slurry is obtained by ball milling for 2 hours at a high speed of 200 revolutions per minute through a coarse mill. Continuously adding 20wt.% of active substance graphite pretreated by ethanol), further performing ball milling at the rotating speed of 200 rpm for 2 hours, and then pouring out the slurry. And (3) adopting a spray drying method to the obtained slurry, setting the air inlet temperature to be 220 ℃, the air outlet temperature to be 110 ℃ and the centrifugal rotating speed to be 17000 r/min, and collecting the obtained spherical powder precursor. And putting the precursor into an inert gas filled sintering furnace, and sintering for 10 hours at the temperature of 750 ℃ in a nitrogen atmosphere to obtain the carbon-coated titanium phosphate compound ceramic powder.
Industrial applicability: the method reduces the production cost of the carbon-coated titanium phosphate compound ceramic powder, improves the purity and the performance of the produced powder, and lays a foundation for the commercial production of the water system sodium ion electrode.
Claims (8)
1. The method for preparing the carbon-coated titanium phosphate compound is characterized in that the chemical formula of the titanium phosphate compound is MxTi2（PO4）3Wherein M is at least one of alkali metals, and x = 1-1.05, the method comprises:
Step 1) taking an alkali metal source, a phosphorus source, a titanium source and a carbon source in a stoichiometric ratio as raw materials, and performing wet ball milling to obtain slurry; the alkali metal source is at least one of carbonate, hydroxide, oxalate, acetate, dihydrogen phosphate and nitrate of alkali metal; the titanium source is any one of titanium dioxide, metatitanic acid, titanic acid and titanium tetrachloride; the phosphorus source is any one of lithium dihydrogen phosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate and ammonium phosphate; the carbon source is any one or more of graphite, activated carbon, hard carbon, graphene and carbon black; the content of a carbon source is 10-20 wt.%, and the carbon source is pretreated by an organic solvent containing hydroxyl functional groups before being added into a ball mill to enhance the wettability; the solvent for wet ball milling is water or a mixed solvent of water and ethanol, and the content of ethanol in the mixed solvent is 0-10 wt.%;
Step 2) obtaining spherical carbon-coated titanium phosphate compound precursor mixed powder by using a centrifugal spray drying method for the slurry;
step 3) sintering the precursor mixed powder by adopting a solid-phase synthesis method to obtain carbon-coated titanium phosphate compound powder; the sintering is carried out at the constant temperature of 600-1000 ℃ for 1-24 hours in a protective atmosphere.
2. The method of claim 1, wherein step 1) comprises:
Mixing an alkali metal source, a titanium source and a phosphorus source according to a molar ratio of (1-1.05) to 2:3, pouring the mixed raw materials into a ball milling barrel, adding deionized water according to 10-50 wt.% of solid content, and ball milling at a rotating speed of 50-300 r/min for 1-5 hours to obtain first slurry; and adding a carbon source into the obtained first slurry, and mixing and ball-milling for 1-5 hours at a rotating speed of 50-300 r/min.
3. The method according to claim 1, wherein in step 1), an antifoaming agent and/or a dispersant is further added, wherein the antifoaming agent is added in an amount of 0.5-5 wt.% of the powder, the dispersant is added in an amount of 0.5-5 wt.% of the powder, the antifoaming agent is a higher alcohol, and the dispersant is at least one selected from polyacrylic acid, sodium hexametaphosphate, polyethylene glycol, fish oil and castor oil.
4. The method according to claim 1, wherein in step 1), the solid content of the obtained slurry is 0-60 wt.%.
5. The method according to claim 4, wherein in the step 1), the solid content of the obtained slurry is 20-30 wt.%.
6. The method as claimed in claim 1, wherein in the step 2), a centrifugal spray drying device is used, the inlet air temperature is controlled to be 100-240 ℃, the outlet air temperature is controlled to be 80-110 ℃, and the centrifugal speed is 10000-20000 rpm.
7. The method as claimed in claim 6, wherein in the step 2), a centrifugal spray drying device is used, and the inlet air temperature is controlled to be 200-240 ℃, the outlet air temperature is controlled to be 100-110 ℃, and the centrifugal speed is controlled to be 12000-15000 r/m.
8. The method according to any one of claims 1 to 7, wherein in the step 3), the deamination is performed at a constant temperature of 200 to 350 ℃ for 1 to 5 hours before the temperature is raised to the sintering temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610821504.9A CN107814564B (en) | 2016-09-13 | 2016-09-13 | Low-cost carbon-coated titanium phosphate compound batch preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610821504.9A CN107814564B (en) | 2016-09-13 | 2016-09-13 | Low-cost carbon-coated titanium phosphate compound batch preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107814564A CN107814564A (en) | 2018-03-20 |
| CN107814564B true CN107814564B (en) | 2019-12-17 |
Family
ID=61601214
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610821504.9A Active CN107814564B (en) | 2016-09-13 | 2016-09-13 | Low-cost carbon-coated titanium phosphate compound batch preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107814564B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108574093B (en) * | 2018-05-08 | 2020-11-06 | 浙江农林大学 | Carbon/titanium pyrophosphate composite material and preparation method thereof |
| CN108911756A (en) * | 2018-08-27 | 2018-11-30 | 宁波伏尔肯科技股份有限公司 | A kind of adjustable silicon carbide ceramics of resistance and preparation method thereof |
| CN109400128B (en) * | 2018-11-08 | 2021-11-30 | 浙江皓翔矿业有限公司 | Pyrophyllite powder-containing aluminum-carbon refractory material and preparation method thereof |
| CN109599547B (en) * | 2018-12-07 | 2022-05-13 | 天津市贝特瑞新能源科技有限公司 | NaTi2(PO4)3-TiO2Preparation method and application of/C composite electrode material |
| CN109665834B (en) * | 2019-03-01 | 2021-08-03 | 郑州大学 | Phase-composition-controllable indium gallium zinc oxide target and preparation method thereof |
| CN111987347B (en) * | 2020-06-22 | 2021-08-03 | 厦门永力鑫新能源科技有限公司 | Phosphate solid electrolyte, solid-phase synthesis method and equipment thereof, and solid-state battery |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102280638A (en) * | 2011-07-04 | 2011-12-14 | 南陵恒昌铜箔制造有限公司 | Vegetable protein carbon cladded nanometer lithium iron phosphate anode material and preparation method thereof |
| CN102556996A (en) * | 2010-12-30 | 2012-07-11 | 中国电子科技集团公司第十八研究所 | Preparation method for high-tap-density lithium iron phosphate |
| CN103779563A (en) * | 2014-01-20 | 2014-05-07 | 重庆特瑞电池材料股份有限公司 | Method for preparing copper/carbon-coated lithium iron phosphate |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2632873B1 (en) * | 2010-10-29 | 2017-07-12 | Corning Incorporated | Dry process for making a large xenotime ceramic block |
-
2016
- 2016-09-13 CN CN201610821504.9A patent/CN107814564B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102556996A (en) * | 2010-12-30 | 2012-07-11 | 中国电子科技集团公司第十八研究所 | Preparation method for high-tap-density lithium iron phosphate |
| CN102280638A (en) * | 2011-07-04 | 2011-12-14 | 南陵恒昌铜箔制造有限公司 | Vegetable protein carbon cladded nanometer lithium iron phosphate anode material and preparation method thereof |
| CN103779563A (en) * | 2014-01-20 | 2014-05-07 | 重庆特瑞电池材料股份有限公司 | Method for preparing copper/carbon-coated lithium iron phosphate |
Non-Patent Citations (1)
| Title |
|---|
| "磷酸盐基电极材料的制备、表征及水系电池的组装";孙家香;《中国优秀硕士学位论文全文数据库工程科技Ⅱ辑》;20170515;第21页第1-3段、第27页第1段 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107814564A (en) | 2018-03-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107814564B (en) | Low-cost carbon-coated titanium phosphate compound batch preparation method | |
| EP2911223B1 (en) | Titanium-niobium composite oxide-based electrode active material and lithium secondary battery using the same | |
| WO2022257311A1 (en) | High-first-efficiency and high-rate silicon-based negative electrode material and preparation method therefor | |
| CN107464918B (en) | Lithium ion secondary battery anode material, lithium ion secondary battery anode, lithium ion secondary battery | |
| CN101997118A (en) | Lithium ferric manganese phosphate as cathode material of lithium ion battery and preparation method thereof | |
| CN109004212B (en) | High-rate lithium manganate positive electrode material and preparation method thereof | |
| EP2760069A1 (en) | Electrode material, electrode and electrode material manufacturing method | |
| CN107732174B (en) | Carbon-coated LiFePO of lithium ion battery4Preparation method of/CNTs composite positive electrode material | |
| WO2011162348A1 (en) | Silicic acid compound, positive electrode for secondary cell, and method for producing secondary cell | |
| CN111048764A (en) | Silicon-carbon composite material and preparation method and application thereof | |
| CN110556517A (en) | Negative electrode material, negative electrode and preparation method of negative electrode | |
| CN103596877A (en) | Method for manufacturing lithium iron phosphate | |
| CN104393272A (en) | Lithium titanate cathode composite material and preparation method | |
| WO2011138964A1 (en) | (silicic acid)-(phosphoric acid) compound, positive electrode for secondary battery, and process for production of secondary battery | |
| CN102097616A (en) | Preparation method of high-energy and high-power density nano-scale lithium iron phosphate powder | |
| CN104600292A (en) | Preparation method for carbon-graphene doubly modified lithium iron phosphate anode material | |
| CN112885992A (en) | Preparation method and application of lithium ion battery negative electrode material | |
| JP2004259471A (en) | Manufacturing method of positive electrode active material for lithium ion battery | |
| CN102208624A (en) | Method for preparing carbon-coated LiFePO4 anode material by using low-temperature solid-phase method | |
| CN106486658A (en) | A kind of solid phase reaction prepares the method for silicon nano material and its application | |
| JP7410301B2 (en) | Negative active material for batteries and method for producing the same | |
| CN112736233B (en) | Lithium ion battery electrode active material, preparation method thereof, electrode and battery | |
| CN109698339A (en) | A kind of lithium titanate composite material and its preparation method and application | |
| CN113745504A (en) | Niobium-tungsten-titanium oxide negative electrode material and preparation method and application thereof | |
| CN102299333A (en) | Preparation method of carbon coated Li4Ti5O12 nano cathode material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220728 Address after: 200050 No. 1295 Dingxi Road, Shanghai, Changning District Patentee after: SHANGHAI INSTITUTE OF CERAMICS, CHINESE ACADEMY OF SCIENCES Address before: 201800 No. 215 Chengbei Road, Shanghai, Jiading District Patentee before: RESEARCH AND DEVELOPMENT CENTER, SHANGHAI INSTITUTE OF CERAMICS Patentee before: SHANGHAI INSTITUTE OF CERAMICS, CHINESE ACADEMY OF SCIENCES |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20221230 Address after: Room 198, 1st Floor, Building 15, No. 42, Jibang Old Street, Zhongxing Town, Chongming District, Shanghai 202163 Patentee after: BenAn energy technology (Shanghai) Co.,Ltd. Address before: 200050 No. 1295 Dingxi Road, Shanghai, Changning District Patentee before: SHANGHAI INSTITUTE OF CERAMICS, CHINESE ACADEMY OF SCIENCES |
|
| TR01 | Transfer of patent right |