CN110729469B - High-purity high-crystallinity MoO2Preparation method of (1) - Google Patents

High-purity high-crystallinity MoO2Preparation method of (1) Download PDF

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CN110729469B
CN110729469B CN201910972440.6A CN201910972440A CN110729469B CN 110729469 B CN110729469 B CN 110729469B CN 201910972440 A CN201910972440 A CN 201910972440A CN 110729469 B CN110729469 B CN 110729469B
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ammonium molybdate
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熊传溪
郑瑜环
胡国华
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Wuhan University of Technology WUT
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/386—Silicon or alloys based on silicon
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The invention discloses high-purity high-crystallinity MoO2The preparation method of (1). Silicon nitrideAdding the powder into absolute ethyl alcohol, and stirring for more than 12 hours until the powder is uniformly dispersed; then adding ammonium molybdate tetrahydrate, and continuously stirring for more than 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate; drying the uniformly mixed solution to obtain powder; placing the obtained powder in a tube furnace, and annealing for 2-48 hours at the temperature of 400-1000 ℃ in Ar atmosphere to obtain powder; uniformly dispersing the obtained powder in NaOH solution, washing precipitates with deionized water and ethanol, and drying in vacuum to obtain MoO2. Compared with a hydrothermal method, the method has better crystallinity and higher purity. The interface oxidation-reduction method is a simple and efficient method for synthesizing high-crystallinity MoO2The method (1).

Description

High-purity high-crystallinity MoO2Preparation method of (1)
Technical Field
The invention belongs to the technical field of materials, and particularly relates to high-purity high-crystallinity MoO2A preparation method of a lithium ion battery cathode material.
Background
The electronic information industry has been developing vigorously over the last several decades. The large volume use of devices such as electric cars, mobile phones, and portable computers has highlighted the advantages of Lithium Ion Batteries (LIBs). The LIBs are small in size, long in service life and good in environmental compatibility, and theoretically have good development prospects. However, the specific capacity of the graphite negative electrode which is industrially used at present is only 372 mAhg-1The use of LIBs in light weight, high power devices, such as electric vehicles, is hindered. Therefore, it is a very important development direction to improve the specific capacity of LIBs negative electrode materials.
Molybdenum dioxide (MoO)2) Has a deformed rutile structure, exhibits metallic properties, and is a good electrical conductor. MoO2Has a band gap of 3.85eV and a conductivity of about MoO33 times of the total weight of the product. Reported to be MoO2There are three crystal forms, the thermodynamically stable monoclinic form (P2)1) Square type (P4)2Nm) and hexagonal (P6)3And/mmc). Based on the unique factors of structure, size, shape and the like, the MoO is enabled2The method has wide application in the fields of catalysis, light-emitting diodes, sensors, batteries, fuel cells, photocatalysts and electrocatalysts, photochromism, electrochromism and the like.
In the LIBs field, negative electrode materials are often plagued by large strain and low conductivity when subjected to electrochemical tests, resulting in rapid decay of electrode capacity and also hindering rate performance of batteries. Most electrode materials generally have low electrical conductivity, for example: the silicon electrode has 4200mAhg-1Ultra high theoretical specific capacity, but its electricityThe conductivity is very low, and the structure is easy to collapse in the process of lithium ion intercalation, so that the release of high specific capacity of the lithium ion is limited. However, MoO2Hardly has the problem of low conductivity, bulk MoO2Resistivity at 300K was 8.8X 10-5Omega cm, which belongs to the conductor range. Research proves that the MoO synthesized by the invention2The defects can be effectively overcome, and excellent electrochemical performance is presented.
Currently synthesized MoO2There are mainly 3 methods: the first method is to reduce MoO at high temperature with hydrogen3MoO formed by this reaction2Often mixed with MoO3Therefore, MoO needs to be added2And MoO3The mixture is calcined in a HCl gas stream until MoO3Complete volatilization of 2HCl and residual MoO2Slowly cooling in hydrogen flow to obtain MoO2. The second method is to reduce MoO with metallic molybdenum3The reaction equipment needs to be thoroughly exhausted, the reaction temperature is as high as 700 ℃, and the reaction time is as long as 40 hours. A third method is to heat the metal molybdenum, MoO in the presence of oxygen2Will be formed as an intermediate product.
Briefly, MoO2Is a material with excellent performance, and explores other simple and convenient methods to synthesize high-purity and high-crystallinity MoO2Is very necessary. MoO2Meets the performance requirements of the LIBs and has good development prospect in the field of the LIBs.
Disclosure of Invention
The invention aims to provide high-purity high-crystallinity MoO2The preparation method of (1).
In order to achieve the purpose, the technical scheme is as follows:
high-purity high-crystallinity MoO2The preparation method comprises the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O
Adding the silicon powder into absolute ethyl alcohol, and stirring for more than 12 hours until the silicon powder is uniformly dispersed; ammonium molybdate tetrahydrate (H) was then added24Mo7N6O24·4H2O), stirring for more than 12 hours continuously to ensure thatUniformly dispersing silicon powder and ammonium molybdate tetrahydrate; drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O powder;
2) preparation of SiOx/MoO2
The obtained Si/H24Mo7N6O24·4H2Placing O powder in a tube furnace, heating to 400-1000 ℃ in Ar atmosphere, annealing for 2-48 hours at the heating rate of 1-15 ℃/min, cooling to room temperature at the cooling rate of 1-15 ℃/min after complete reaction, and obtaining the SiOx/MoO2Powder;
3) etching SiOxPreparation of MoO2
Mixing SiOx/MoO2Uniformly dispersing the powder in NaOH solution, washing the precipitate with deionized water and ethanol, and drying in vacuum to obtain MoO2。
According to the scheme, the mass ratio of the silicon powder to the ammonium molybdate tetrahydrate in the step 1 is (0.5-3): 1; the total adding amount of the silicon powder and the ammonium molybdate tetrahydrate is 5-40 g/L of absolute ethyl alcohol.
According to the scheme, the silicon powder in the step 1 is in submicron grade, the average particle size is 100nm, the purity is more than 99.9 percent, and the specific surface area is 8.30m2(ii) a volume density of 1.89g/cm3The crystal form is spherical.
According to the scheme, the concentration of the NaOH aqueous solution in the step 3 is 0.2-1 mol/L.
In the annealing process in the step 2, the oxidation-reduction reaction is carried out at the interface of silicon and ammonium molybdate tetrahydrate, and Si is oxidized into SiOxMo element in ammonium molybdate tetrahydrate is reduced to MoO2. Preparation of high-purity high-crystallinity MoO by interfacial redox reaction2Is a safe and reliable method, and the reaction is environment-friendly. On one hand, the raw materials adopted in the experiment are silicon powder and ammonium molybdate tetrahydrate, so that the source is wide and the price is low; on the other hand, the method has low requirements on instruments and equipment and is safe to operate.
The invention selects the oxidation-reduction method to prepare MoO2. The preparation method can realize large-area continuous production due to rapid oxidation-reduction reactionHas practical application prospect. In addition, silicon powder and ammonium molybdate tetrahydrate are easily and uniformly dispersed in the ethanol solution, so that a good interface can be formed between the two substances, the contact area is increased, and the reaction yield is improved. MoO synthesized by redox reaction in the invention2The crystallinity and the purity are very high, and theoretically, the material is more favorable for exerting excellent mechanical property, electrical property, optical property and other structure-related properties.
The invention has the beneficial effects that:
the ethanol solvent adopted by the invention can ensure that the silicon powder and the ammonium molybdate tetrahydrate can be uniformly dispersed in the solution. After the solution is dried, ammonium molybdate tetrahydrate can be adsorbed on the surface of the silicon particles, so that sufficient reaction sites are provided for the subsequent interfacial redox reaction. Under high temperature conditions, silicon and ammonium molybdate tetrahydrate can generate oxidation-reduction reaction, wherein silicon is oxidized, and molybdenum element in the ammonium molybdate tetrahydrate is reduced. The method has few side reactions in the synthesis process, and finally obtains MoO with high purity and high crystallinity2. The material shows good cycle stability and rate capability when being applied to a lithium ion battery cathode material, even when the current density is 4000mA/g, MoO2The electrode still exhibited a stable specific capacity of 146 mAh/g.
The invention selects an interfacial redox method to prepare MoO2In which MoO2Compared with MoO synthesized by a hydrothermal method2Better crystallinity and higher purity. The interface oxidation-reduction method is a simple and efficient method for synthesizing high-crystallinity MoO2The method (1). Moreover, the reduction of metal oxides by using silicon as a reducing substance has certain reference value for other materials.
The invention has the advantages of simple synthesis process, high product purity, high crystallinity, low cost, large-scale synthesis and obvious economic benefit. Finally, the MoO is added2Preparing electrode slurry as an active material and assembling the button-shaped lithium ion half cell. MoO prepared by the interfacial redox reaction2High crystallinity, high purity, MoO2The electrode shows excellent rate performance and cyclicity in a Lithium Ion Battery (LIB)Can be used. MoO2Electrode at 100mAg-1Lower 507mAh g-1High initial specific discharge capacity of 4000mA g-1Also exhibits 146mAh g at a high current density-1Excellent rate capability. Further, MoO2The electrode was at 1000mA g-1The product also shows 300mAh g after 200 cycles-1High specific capacity of (2).
Drawings
FIG. 1: MoO obtained in example 12And Bulk MoO in comparative example 12X-ray diffraction (XRD) pattern of (a);
FIG. 2: MoO obtained in example 12And Bulk MoO in comparative example 12As LIBs cathode materials, cycle performance curves and coulombic efficiencies within 200 cycles at 1000 mA/g;
FIG. 3: MoO obtained in example 12And Bulk MoO in comparative example 12The rate capability of (a);
FIG. 4: MoO obtained in example 12Scanning Electron Microscope (SEM) images of (a).
Detailed Description
The following examples further illustrate the technical solutions of the present invention, but should not be construed as limiting the scope of the present invention.
Example 1
Preparation of high purity high crystallinity MoO2The method comprises the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O: 1g of silicon powder (submicron grade, average particle size of 100nm, purity of more than 99.9 percent and specific surface area of 8.30 m) is weighed2(ii) a volume density of 1.89g/cm3Spherical crystal form) was added to a beaker containing 200mL of absolute ethanol, and stirred with a magnet at room temperature for 12 hours until uniformly dispersed. Then 1g of ammonium molybdate tetrahydrate (H) was added to the beaker24Mo7N6O24·4H2And O), continuing stirring by the magnet for 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate. Then, drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O。
2)Preparation of SiOx/MoO2: mixing Si/H24Mo7N6O24·4H2The O powder was placed in a tube furnace. Subsequently, annealing at 500 ℃ for 4 hours in an Ar atmosphere at a heating rate of 5 ℃/min; cooling to room temperature at a cooling rate of 1-15 ℃/min. At high temperature, oxidation-reduction reaction occurs at the interface of silicon and ammonium molybdate tetrahydrate, and Si is oxidized into SiOxMo element in ammonium molybdate tetrahydrate is reduced to MoO2After the reaction is completed, SiO is obtainedx/MoO2。
3) Etching SiOxPreparation of MoO2: mixing SiOx/MoO2The powder was uniformly dispersed in 500mL of NaOH (0.5mol/L) solution and stirred for 24 h. Washing the precipitate with deionized water and ethanol, and vacuum drying to obtain MoO2。
MoO prepared in this example was subjected to a Bruker D8 DISCOVER target-transfer X-ray diffractometer2The composition and the crystal structure of (a) were tested. MoO is shown by the XRD spectrum of FIG. 12With diffraction peaks corresponding to all the crystal planes of a standard PDF card (PDF # 65-5787). MoO prepared in this example2The sharp crystallization peak means that the crystallinity and purity are high. MoO2Shows diffraction peaks at 25.9 °, 36.8 °, 41.5 °, 53.5 °, 60.3 °, 66.6 °, 78.7 °, respectively, corresponding to MoO2The (011), (211), (210), (311), (013), (402), (133) crystal planes of (a). The results show that the micron silicon particles can be used for synthesizing high-purity high-crystallinity MoO2The template of (1). MoO Pair Using LAND (CT2001A) Battery System2The electrode is subjected to cyclic stability and rate capability test, MoO2Active material for LIBs negative electrode material, counter electrode was lithium plate, active material: acetylene black: PVDF (w/w) ═ 8: 1: 1. as shown in FIG. 2, MoO was determined from the stability of the cycle2The initial specific capacity of the electrode is 507mAh/g, which is relatively close to MoO2The theoretical specific capacity of the capacitor is 838mAh/g, the initial specific capacity is 305mAh/g under the current density of 1000mA/g, and after 200 cycles, the specific capacity reaches 300mAh/g and is kept stable; as shown in FIG. 3, it can be seen from the rate capability that MoO is present even at a high current density of 4000mA/g2The electrode still exhibited a high specific capacity of 146 mAh/g.
FIG. 4 shows the MoO prepared in this example2SEM picture of (1), as can be seen MoO2Presents a structure of irregular particles in bulk, smooth surface and MoO2The grain sizes of the crystal grains are different, about 0.2-1.6 μm, and the interval with the largest number is 200-300 nm.
Example 2
Preparation of high purity high crystallinity MoO2The method comprises the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O: 0.5g of silicon powder (submicron grade, average particle size of 100nm, purity of more than 99.9 percent and specific surface area of 8.30 m) is weighed2(ii) a volume density of 1.89g/cm3Spherical crystal form) was added to a beaker containing 200mL of absolute ethanol, and stirred with a magnet at room temperature for 12 hours until uniformly dispersed. Then 1g of ammonium molybdate tetrahydrate (H) was added to the beaker24Mo7N6O24·4H2And O), continuing stirring by the magnet for 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate. Then, drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O。
2) Preparation of SiOx/MoO2: mixing Si/H24Mo7N6O24·4H2The O powder was placed in a tube furnace. Subsequently, annealing at 400 ℃ for 48 hours in Ar atmosphere at a heating rate of 1 ℃/min; cooling to room temperature at a cooling rate of 1-15 ℃/min. At high temperature, oxidation-reduction reaction occurs at the interface of silicon and ammonium molybdate tetrahydrate, and Si is oxidized into SiOxMo element in ammonium molybdate tetrahydrate is reduced to MoO2After the reaction is completed, SiO is obtainedx/MoO2。
3) Etching SiOxPreparation of MoO2: mixing SiOx/MoO2The powder was uniformly dispersed in a 500mL NaOH (0.5mol/L) solution and stirred for 24 h. Washing the precipitate with deionized water and ethanol, and vacuum drying to obtain MoO2。
Using Bruker D8 DISCOVER target X-ray diffractometer on MoO prepared in the example2The composition and the crystal structure of (a) were tested. MoO synthesized in this example2With diffraction peaks corresponding to all the crystal planes of a standard PDF card (PDF # 65-5787). MoO prepared in this example2The sharp crystallization peak means that the crystallinity and purity are high. MoO2Shows diffraction peaks at 25.9 °, 36.8 °, 41.5 °, 53.5 °, 60.3 °, 66.6 °, 78.7 °, respectively, corresponding to MoO2The (011), (211), (210), (311), (013), (402), (133) crystal planes of (a). The result shows that the ratio of the silicon powder to the ammonium molybdate tetrahydrate can synthesize high-purity high-crystallinity MoO2。
Example 3
Preparation of high purity high crystallinity MoO2The method comprises the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O: 3g of silicon powder (submicron grade, average particle size of 100nm, purity of more than 99.9 percent and specific surface area of 8.30 m) are weighed2(ii) a volume density of 1.89g/cm3Spherical crystal form) was added to a beaker containing 200mL of absolute ethanol, and stirred with a magnet at room temperature for 12 hours until uniformly dispersed. Then 1g of ammonium molybdate tetrahydrate (H) was added to the beaker24Mo7N6O24·4H2And O), continuing stirring by the magnet for 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate. Then, drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O。
2) Preparation of SiOx/MoO2: mixing Si/H24Mo7N6O24·4H2The O powder was placed in a tube furnace. Subsequently, annealing at 1000 ℃ for 2 hours in Ar atmosphere at a heating rate of 15 ℃/min; cooling to room temperature at a cooling rate of 1-15 ℃/min. At high temperature, oxidation-reduction reaction occurs at the interface of silicon and ammonium molybdate tetrahydrate, and Si is oxidized into SiOxMo element in ammonium molybdate tetrahydrate is reduced to MoO2After the reaction is completed, SiO is obtainedx/MoO2。
3) Etching ofSiOxPreparation of MoO2: mixing SiOx/MoO2The powder was uniformly dispersed in 500mL of NaOH (0.5mol/L) solution and stirred for 24 h. Washing the precipitate with deionized water and ethanol, and vacuum drying to obtain MoO2。
MoO prepared in this example was subjected to a Bruker D8 DISCOVER target-transfer X-ray diffractometer2The composition and the crystal structure of (a) were tested. MoO synthesized in this example2With diffraction peaks corresponding to all the crystal planes of a standard PDF card (PDF # 65-5787). MoO prepared in this example2The sharp crystallization peak means that the crystallinity and purity are high. MoO2Shows diffraction peaks at 25.9 °, 36.8 °, 41.5 °, 53.5 °, 60.3 °, 66.6 °, 78.7 °, respectively, corresponding to MoO2The (011), (211), (210), (311), (013), (402), (133) crystal planes of (a). The result shows that the ratio of the silicon powder to the ammonium molybdate tetrahydrate can synthesize high-purity high-crystallinity MoO2。
Example 4
Preparation of high purity high crystallinity MoO2The method comprises the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O: weighing 2g of silicon powder (submicron grade, average particle size of 100nm, purity of more than 99.9%, specific surface area of 8.30 m)2(ii) a volume density of 1.89g/cm3Spherical crystal form) was added to a beaker containing 200mL of absolute ethanol, and stirred with a magnet at room temperature for 12 hours until uniformly dispersed. Then 1g of ammonium molybdate tetrahydrate (H) was added to the beaker24Mo7N6O24·4H2And O), continuing stirring by the magnet for 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate. Then, drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O。
2) Preparation of SiOx/MoO2: mixing Si/H24Mo7N6O24·4H2The O powder was placed in a tube furnace. Subsequently, annealing at 500 ℃ for 4 hours in an Ar atmosphere at a heating rate of 5 ℃/min; cooling to room temperature at a cooling rate of 1-15 ℃/min. At high temperature, oxidation-reduction reaction occurs at the interface of silicon and ammonium molybdate tetrahydrate, and Si is oxidized into SiOxMo element in ammonium molybdate tetrahydrate is reduced to MoO2After the reaction is completed, SiO is obtainedx/MoO2。
3) Etching SiOxPreparation of MoO2: mixing SiOx/MoO2The powder was uniformly dispersed in 500mL of NaOH (0.5mol/L) solution and stirred for 24 h. Washing the precipitate with deionized water and ethanol, and vacuum drying to obtain MoO2。
MoO prepared in this example was subjected to a Bruker D8 DISCOVER target-transfer X-ray diffractometer2The composition and the crystal structure of (a) were tested. MoO synthesized in this example2With diffraction peaks corresponding to all the crystal planes of a standard PDF card (PDF # 65-5787). MoO prepared in this example2The sharp crystallization peak means that the crystallinity and purity are high. MoO2Shows diffraction peaks at 25.9 °, 36.8 °, 41.5 °, 53.5 °, 60.3 °, 66.6 °, 78.7 °, respectively, corresponding to MoO2The (011), (211), (210), (311), (013), (402), (133) crystal planes of (a). The result shows that the ratio of the silicon powder to the ammonium molybdate tetrahydrate can synthesize high-purity high-crystallinity MoO2。
Comparative example 1
Bulk MoO2, purchased from shanghai alading biochemistry technologies ltd, with a purity of 99.9%.
Bulk MoO of this example was subjected to a Bruker D8 DISCOVER target-transfer X-ray diffractometer2The crystal structure of (2) was tested. Bulk MoO is shown in the XRD spectrum of FIG. 12The XRD diffraction peak shape of the crystal is very sharp, which shows that the crystallinity of the crystal is very high, Bulk MoO2With diffraction peaks corresponding to all the crystal planes of a standard PDF card (PDF # 65-5787). Pairing Bulk MoO with LAND (CT2001A) battery system2The test of the cycling stability and the rate capability is carried out, Bulk MoO2Active material for LIBs negative electrode material, counter electrode was lithium plate, active material: acetylene black: PVDF (w/w) ═ 8: 1: 1. as shown in FIG. 2, Bulk MoO was measured for the stability of the cycle2The initial specific capacity of the electrode is 440mAh/g and the power is 1000mA/gThe initial specific capacity under the current density is 160mAh/g, and after 200 cycles, the specific capacity is only 124 mAh/g; as shown in FIG. 3, the rate capability of Bulk MoO was measured at a high current density of 4000mA/g2The electrode only exhibits a specific capacity of 60 mAh/g.

Claims (4)

1. MoO (MoO)2The preparation method is characterized by comprising the following steps:
1) preparation of Si/H24Mo7N6O24·4H2O
Adding the silicon powder into absolute ethyl alcohol, and stirring for more than 12 hours until the silicon powder is uniformly dispersed; then adding ammonium molybdate tetrahydrate, and continuously stirring for more than 12 hours to uniformly disperse the silicon powder and the ammonium molybdate tetrahydrate; drying the uniformly mixed solution to obtain Si/H24Mo7N6O24·4H2O powder;
2) preparation of SiOx/MoO2
The obtained Si/H24Mo7N6O24·4H2Placing O powder in a tube furnace, heating to 400-1000 ℃ in Ar atmosphere, annealing for 2-48 hours at the heating rate of 1-15 ℃/min, cooling to room temperature at the cooling rate of 1-15 ℃/min after complete reaction, and obtaining the SiOx/MoO2Powder;
3) etching SiOxPreparation of MoO2
Mixing SiOx/MoO2Uniformly dispersing the powder in NaOH solution, washing the precipitate with deionized water and ethanol, and drying in vacuum to obtain MoO2。
2. The MoO of claim 12The preparation method is characterized in that in the step 1, the mass ratio of the silicon powder to the ammonium molybdate tetrahydrate is (0.5-3): 1; the total adding amount of the silicon powder and the ammonium molybdate tetrahydrate is 5-40 g/L of absolute ethyl alcohol.
3. The MoO of claim 12The preparation method is characterized in that the silicon powder in the step 1 is submicron grade, and the average grain diameter is 100nm, purity > 99.9%, specific surface area 8.30m2(ii) a volume density of 1.89g/cm3The crystal form is spherical.
4. The MoO of claim 12The preparation method is characterized in that the concentration of the NaOH aqueous solution in the step 3 is 0.2-1 mol/L.
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Citations (2)

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Publication number Priority date Publication date Assignee Title
EP2184798A1 (en) * 2008-11-10 2010-05-12 Samsung Electronics Co., Ltd. Anode active material, anode comprising the anode active material, lithium battery comprising the anode, and method of preparing the anode active material.
CN102583545A (en) * 2012-03-06 2012-07-18 北京工业大学 Preparation method of three-dimensional ordered mesoporous molybdenum oxide

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Publication number Priority date Publication date Assignee Title
DE102008051784B4 (en) * 2008-10-17 2012-02-02 H.C. Starck Gmbh Process for the preparation of molybdenum metal powder, molybdenum metal powder and its use

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2184798A1 (en) * 2008-11-10 2010-05-12 Samsung Electronics Co., Ltd. Anode active material, anode comprising the anode active material, lithium battery comprising the anode, and method of preparing the anode active material.
CN102583545A (en) * 2012-03-06 2012-07-18 北京工业大学 Preparation method of three-dimensional ordered mesoporous molybdenum oxide

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