Preparation method of hydroxyl nickel fluoride / hydrated ferronickel fluoride / ferric fluoride multiphase functional nano material

Abstract

The invention discloses a preparation method of a hydroxyl nickel fluoride / hydrated ferronickel fluoride / ferric fluoride multiphase functional nano material, and relates to a preparation method of a multiphase functional nano composite material, the preparation method comprises the following steps: 1, generating a precipitate of a hydrated ferronickel fluoride / hydrated ferronickel fluoride / ferric fluoride multiphase composite material (NiF2. 4H2O / NiFeF5. 7H2O. / Fe1. 9F4.95. 0.95 H2O) through liquid-phase synthesis, and then centrifuging and washing; the second step is solvothermal treatment, the hydrated ferric fluoride / hydrated ferronickel fluoride / ferric fluoride multiphase composite material (NiF2. 4H2O / NiFeF5. 7H2O / Fe < 1.9 > F < 4.95. 0.95 > H2O) prepared in the first step and an alcohol solvent are placed in a reaction kettle to be subjected to solvothermal treatment, and the hydroxyl nickel fluoride / hydrated ferronickel fluoride / ferric fluoride multiphase functional nanocomposite material (Ni4OHF7 / NiFeF5. 2H2O / Fe < 1.9 > F < 4.75. 0.95 > H2O) is obtained. The material contains various anions (fluorine ions and hydroxyl groups) and rich redox valence states of nickel and iron bimetals, and has a plurality of application values. The obtained nanostructure material can be applied to the related fields and many fields of electrochemistry, electrocatalysis and the like.

Description

Technical Field

[0001] The invention relates to a method for preparing a multiphase functional nano composite material, in particular to a method for preparing a multiphase functional nano material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride. Background Art

[0002] Nickel hydroxyfluoride / hydrated nickel iron fluoride / iron fluoride multiphase functional nanocomposite (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O) contains a variety of Ni and Fe metal active ions, and a variety of anions (hydroxyl, fluoride). The high electronegativity of fluoride ions, the affinity of hydroxyl groups for certain liquid phases, and the rich redox valence of iron and nickel ions make each single phase in this composite material have some excellent physical and chemical properties. Hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride multiphase functional nanocomposite material (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O) is predicted to not only combine the advantages of the three, but also have additional comprehensive excellent performance. In addition, nano-sizing will further bring various surface and quantum size effects to it, thereby increasing its basic research and application value. Multiphase functional nanocomposite materials of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 0.95H2O) can be used in batteries, electrocatalysis or other energy fields and many other fields. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / ferric fluoride. The present invention adopts a two-step method for low-temperature preparation. The first step is liquid phase synthesis to generate hydrated nickel iron fluoride material; the second step is solvent thermal treatment with alcohols and water, and mixing them evenly to form a solid-liquid mixture; the solid-liquid mixture is subjected to hydrothermal / solvent thermal reaction (80-150°C) in a reactor to obtain hydrated nickel iron fluoride functional nanomaterial, which has excellent physical and chemical properties and increases the basic research and application value of materials in this field.

[0004] The objective of the present invention is achieved through the following technical solutions: A method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the method comprising the following preparation process: (1) The first step is liquid phase synthesis: a solution containing a fluoride salt precursor is mixed with a solution containing an iron salt and a nickel salt precursor. The fluoride salt reacts with the iron salt and the nickel salt to form a multiphase composite material of hydrated iron fluoride / hydrated nickel iron fluoride / iron fluoride (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95 0.95H2O) precipitation, followed by centrifugation and washing; (2) The second step is solvent thermal treatment: the multiphase composite material (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95 ·0.95H2O) and an alcohol solvent were placed in a reactor for solvothermal treatment; during the solvothermal treatment, the crystal water was removed and hydrolyzed, and the morphology and phase transformation were accompanied during the process, and finally a multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O).

[0005] The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / ferric fluoride, the multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / ferric fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 0.95H2O) have particle sizes ranging from 0.01 nm to 500 nm; each particle is composed of nanoregions (0.1-20 nm) of each of these three phases.

[0006] The method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the fluoride salt precursor in the liquid phase synthesis is one or two of NH4F and NH4HF2, the iron salt precursor is one or more of Fe(NO3)3·9H2O, FeCl3·6H2O, Fe(OH)(CH3COO)2, Fe2(SO4)3 and trivalent iron salts, and the nickel salt precursor is one or more of NiCl2·6H2O, NiSO4 and any divalent nickel salt.

[0007] In the method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the ratio of the iron salt precursor and the nickel salt precursor in the liquid phase synthesis satisfies that the molar ratio of Fe:Ni is between 0.001:1 and 999:1.

[0008] The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the solvent in the fluorine-containing salt precursor solution in the liquid phase synthesis is one or more of water, ethanol, various alcohols and organic solvents; the solvent in the iron salt and nickel salt precursor solution is one or more of water, ethanol, various alcohols and organic solvents. In the method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the alcohol in the solvent thermal treatment is one or more of any alcohols with hydroxyl groups (such as ethanol, ethylene glycol, glycerol).

[0009] In the method for preparing the multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the reaction temperature in the solvent thermal treatment is 80-350°C.

[0010] In the method for preparing the multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, the heat preservation time of the reaction in the solvent thermal treatment is 0.1-24 hours.

[0011] The advantages and effects of the present invention are: 1. The multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O) is nanometer-sized, and each nanoparticle is composed of nano-regions of three phases.

[0012] 2. The present invention obtains for the first time a multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O) and its nanoparticles.

[0013] 3. The hydrated nickel-iron fluoride functional nanomaterial (NiFeF5·2H2O) of the present invention contains Ni, Fe metal active ions, and fluoride ions. The high electronegativity of fluoride ions, the rich redox valence of iron ions and nickel ions, and the unique crystal structure make this material have some excellent physical and chemical properties. In addition, nano-sizing will further bring it various surface and quantum size effects, thereby increasing its basic research and application value. The prepared material can be used in batteries, electrocatalysis or other energy fields and many application fields. DETAILED DESCRIPTION

[0014] The present invention is described in detail below with reference to the embodiments.

[0015] The present invention is a multi-phase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O). Hydrated nickel-iron fluoride functional nanomaterial (NiFeF5·2H2O) contains Ni, Fe metal active ions, and fluoride ions. The high electronegativity of fluoride ions, the rich redox valence states of iron ions and nickel ions, and the unique crystal structure give this material certain excellent physical and chemical properties. In addition, nano-sizing will further bring it various surface and quantum size effects, thereby increasing its basic research and application value. It can be applied to batteries, electrocatalysis or other energy fields and many application fields. The present invention adopts a two-step method for low-temperature preparation. The first step of liquid phase synthesis involves mixing a solution of a fluoride salt precursor with a solution containing an iron salt and a nickel salt precursor, and a chemical reaction occurs between the fluoride salt and the iron salt and the nickel salt to generate a hydrated nickel-iron fluoride material. The second step of solvent thermal treatment involves using the hydrated nickel iron fluoride material prepared in the first step as a precursor, mixing it with alcohols and water to form a solid-liquid mixture; the solid-liquid mixture is subjected to a hydrothermal / solvent thermal reaction (80-150°C) in a reactor to obtain a hydrated nickel iron fluoride functional nanomaterial. Example

[0016] Nickel hydroxyfluoride / hydrated nickel iron fluoride / iron fluoride multiphase functional nanocomposite (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O): Prepare 20 mL of aqueous solution containing 0.25g PEG4000, place 2.12 g of NH4HF2 powder in the above clear solution, and stir with a magnetic stirrer until mixed evenly. Prepare 60 mL of anhydrous ethanol containing 1g PEG4000, weigh 4.4 g of NiCl2·6H2O powder and 4.0 g of FeCl3·6H2O powder, place them in the above clear solution, and stir with a magnetic stirrer until mixed evenly. Add the solution containing NH4HF2 to the solution containing NiCl2·6H2O and FeCl3·6H2O at a slow rate of 20 drops / min. Continue stirring for 2 hours. Centrifuge, wash, and dry to obtain a multiphase composite material of hydrated iron fluoride / hydrated nickel iron fluoride / iron fluoride (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95 0.95H2O) powder.

[0017] The multiphase composite material of hydrated iron fluoride / hydrated nickel iron fluoride / iron fluoride (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95·0.95H2O) was added to a mixture of "45 mL ethanol and 1 mL deionized water", ultrasonically dispersed, and then placed in a 50 mL hydrothermal kettle at 120°C / 10h. After cooling, the hydrothermal kettle was opened, the supernatant was poured out, and the remainder was poured into a test tube and centrifuged. Finally, it was placed in an electric constant temperature drying oven at 60°C and dried for 2 hours to obtain a multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 0.95H2O) powder.

Claims

1. A method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride, characterized in that: The method comprises the following preparation process: (1) The first step is liquid phase synthesis: a solution containing a fluoride salt precursor is mixed with a solution containing an iron salt and a nickel salt precursor. The fluoride salt reacts with the iron salt and the nickel salt to form a multiphase composite material of hydrated iron fluoride / hydrated nickel iron fluoride / iron fluoride (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95 0.95H2O) precipitation, followed by centrifugation and washing; (2) The second step is solvent thermal treatment: the multiphase composite material (NiF2·4H2O / NiFeF5·7H2O / Fe 1.9 F 4.95 ·0.95H2O) and an alcohol solvent were placed in a reactor for solvothermal treatment; during the solvothermal treatment, the crystal water was removed and hydrolyzed, and the morphology and phase transformation were accompanied during the process, and finally a multiphase functional nanocomposite material of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 ·0.95H2O).

2. The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The multiphase functional nanocomposite material of nickel hydroxyfluoride / hydrated nickel iron fluoride / iron fluoride (Ni4OHF7 / NiFeF5·2H2O / Fe 1.9 F 4.75 0.95H2O) have particle sizes ranging from 0.01 nm to 500 nm; each particle is composed of nanoregions (0.1-20 nm) of each of these three phases.

3. The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The fluoride salt precursor in the liquid phase synthesis is one or two of NH4F and NH4HF2, the iron salt precursor is one or more of Fe(NO3)3·9H2O, FeCl3·6H2O, Fe(OH)(CH3COO)2, Fe2(SO4)3 and trivalent iron salts, and the nickel salt precursor is one or more of NiCl2·6H2O, NiSO4 and divalent nickel salts.

4. The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The ratio of the iron salt precursor and the nickel salt precursor in the liquid phase synthesis satisfies that the molar ratio of Fe:Ni is between 0.001:1 and 999:

1.

5. The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The solvent in the fluorine-containing salt precursor solution in the liquid phase synthesis is one or more of water, ethanol, and alcohol organic solvents; the solvent in the iron salt and nickel salt precursor solution is one or more of water, ethanol, and alcohol organic solvents.

6. The method for preparing a multiphase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 5, characterized in that: The alcohol in the solvent thermal treatment is one or more of any alcohols with hydroxyl groups (such as ethanol, ethylene glycol, glycerol).

7. The method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The reaction temperature in the solvothermal treatment is 80 - 350°C.

8. The method for preparing a multi-phase functional nanomaterial of hydroxy nickel fluoride / hydrated nickel iron fluoride / iron fluoride according to claim 1, characterized in that: The reaction temperature holding time in the solvent thermal treatment is 0.1-24 hours.