Preparation method, product and application of gold-doped magnesium vanadate nitride

Abstract

The invention relates to a preparation method of gold-doped magnesium vanadate nitride as well as a product and application thereof. The gold-doped magnesium vanadate nitride is prepared through a chemical solution method and nitridation in an argon / ammonia gas mixed atmosphere. Magnesium vanadate is modified through nitridation, so that the diffusivity of ions can be improved, active sites can be increased, an interface is optimized, the electrochemical performance of the material is improved, and the electrochemical performance of the material is further improved through gold doping. The preparation process is relatively simple and easy to operate.

Description

Technical Field

[0001] The present invention relates to a method for preparing a magnesium electric positive electrode material, and in particular to a method for preparing gold-doped magnesium vanadate nitride, and a product and application thereof. Background Art

[0002] With the development of human society, the contradiction between global energy resource shortages and the ever-increasing demand for energy is becoming increasingly acute. Developing high-energy-density battery systems has become a primary goal in current power systems. While lithium-ion batteries, with their high energy density and environmental friendliness, are widely used in portable electronic devices such as mobile phones and laptops, as well as in electric bicycles and electric vehicles, their safety remains a major concern, and their application as power batteries remains a work in progress. Magnesium, one of the most abundant light metals on Earth, is widely used in a wide range of fields due to its excellent physical and chemical properties. Currently, much research on secondary magnesium batteries is based on secondary lithium-ion batteries. Because magnesium and lithium occupy diagonal positions in the periodic table, and despite having similar atomic radii and chemical properties, magnesium's melting point (648.8°C) is much higher than lithium's (180.5°C) and its metallic mobility is less pronounced, making secondary magnesium batteries safer. While its specific capacity isn't as high as lithium (3862 mAh g⁻¹), it's still quite impressive (2205 mAh g⁻¹). Furthermore, my country has abundant magnesium resources, making it significantly cheaper than lithium. Furthermore, magnesium is environmentally friendly, leading to increasing interest in secondary magnesium batteries.

[0003] Magnesium vanadate, a layered monoclinic crystal, is currently used as a cathode material for magnesium-ion batteries and is considered a promising material. To improve the electrochemical performance of magnesium vanadate as a magnesium-ion battery material, various methods have been used to modify the material.

[0004] The present invention provides a method for preparing gold-doped magnesium vanadate nitride. The method prepares gold-doped magnesium vanadate nitride via a chemical solution method and nitridation in an argon / ammonia mixed atmosphere. Modifying the magnesium vanadate via nitridation not only increases ion diffusion but also increases active sites and optimizes the interface, thereby improving the electrochemical performance of the material. Gold doping further enhances the electrochemical performance of the material. The preparation process is relatively simple and easy to operate. Summary of the Invention

[0005] In order to overcome the shortcomings of the existing magnesium vanadate in that the electrochemical performance is not high enough, the present invention aims to provide a preparation method of gold-doped magnesium vanadate nitride.

[0006] Another object of the present invention is to provide a gold-doped magnesium vanadate nitride product obtained by the above method.

[0007] Another object of the present invention is to provide an application of the above product.

[0008] The object of the present invention is achieved by the following scheme: A method for preparing gold-doped magnesium vanadate nitride, characterized in that silver-doped magnesium vanadate nitride is prepared by a chemical solution method and nitridation in an argon / ammonia mixed atmosphere, the specific steps of the method are: (1) Dissolve 5 mmol of soluble vanadate and 20 mmol of oxalic acid in 50 mL of distilled water, labeled as solution A. (2) Disperse 0.01-0.05 mmol of haloauric acid, 3 mmol of soluble magnesium salt, and 9 mmol of oxalic acid in 30 mL of organic solvent, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 120-180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180-200 °C for 8-10 h, wash with ethanol 3-5 times, filter, and dry in a vacuum oven at 60-80 °C for 20-24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 500-700°C and 1-5°C min -1 calcined at a heating rate of 1-5 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate is heated at 700-750 °C for 1-2 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

[0009] The present invention provides a method for preparing gold-doped magnesium vanadate nitride. The method prepares gold-doped magnesium vanadate nitride via a chemical solution method and nitridation in an argon / ammonia mixed atmosphere. Modifying the magnesium vanadate via nitridation not only increases ion diffusion but also increases active sites and optimizes the interface, thereby improving the electrochemical performance of the material. Gold doping further enhances the electrochemical performance of the material. The preparation process is relatively simple and easy to operate.

[0010] Preferably, in step (1), the vanadium oxysalt is one of sodium vanadate, potassium vanadate or lithium vanadate or a combination thereof.

[0011] Preferably, in the step (2), the haloauric acid is one of chloroauric acid and bromoauric acid or a combination thereof.

[0012] Preferably, in step (2), the magnesium salt is one or a combination of magnesium acetate, magnesium nitrate or magnesium chloride.

[0013] Preferably, in step (2), the organic solvent is one of ethanol, methanol or propanol or a combination thereof.

[0014] The present invention provides a gold-doped magnesium vanadate nitride material, which is prepared according to any of the above methods.

[0015] The present invention provides an application of a gold-doped magnesium vanadate nitride material in battery materials.

[0016] Beneficial effects: The present invention provides a method for preparing gold-doped magnesium vanadate nitride. The method prepares gold-doped magnesium vanadate nitride via a chemical solution method and nitridation in an argon / ammonia mixed atmosphere. Modifying the magnesium vanadate via nitridation not only increases ion diffusion but also increases active sites and optimizes the interface, thereby improving the electrochemical performance of the material. Gold doping further enhances the electrochemical performance of the material. The preparation process is relatively simple and easy to operate. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] Example 1 A gold-doped magnesium vanadate nitride material is prepared according to the following steps: (1) Dissolve 5 mmol sodium vanadate and 20 mmol oxalic acid in 50 mL distilled water, labeled solution A. (2) Disperse 0.01 mmol of chloroauric acid, 3 mmol of magnesium nitrate, and 9 mmol of oxalic acid in 30 mL of organic solvent propanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 120 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180 °C for 10 h, wash with ethanol five times, filter, and dry in a vacuum oven at 80 °C for 20 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 500 °C and 1 °C min -1 calcined at a heating rate of 5 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate was heated at 750 °C for 1 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

[0019] Example 2 A gold-doped magnesium vanadate nitride material was prepared similarly to Example 1 by the following steps: (1) Dissolve 5 mmol potassium vanadate and 20 mmol oxalic acid in 50 mL distilled water, labeled solution A. (2) Disperse 0.03 mmol of chloroauric acid, 3 mmol of soluble magnesium salt, and 9 mmol of oxalic acid in 30 mL of organic solvent propanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 200 °C for 8 h, wash with ethanol three times, filter, and dry in a vacuum oven at 60 °C for 24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 700 °C and 2 °C min -1 calcined at a heating rate of 2 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate was heated at 750 °C for 1 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

[0020] Example 3 A gold-doped magnesium vanadate nitride material was prepared similarly to Example 1 by the following steps: (1) Dissolve 5 mmol of lithium vanadate and 20 mmol of oxalic acid in 50 mL of distilled water, labeled as solution A; (2) Disperse 0.05 mmol of bromoauric acid, 3 mmol of soluble magnesium chloride, and 9 mmol of oxalic acid in 30 mL of the organic solvent methanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180 °C for 10 h, wash with ethanol five times, filter, and dry in a vacuum oven at 80 °C for 24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 600 °C and 3 °C min -1 calcined at a heating rate of 3 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate was heated at 700 °C for 2 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

[0021] Electrical properties of gold-doped magnesium vanadate nitride obtained in Examples 1 to 3: The electrochemical performance of the obtained gold-doped magnesium vanadate nitride at a current density of 100 mA / g is shown in Table 1: .

Claims

1. A method for preparing gold-doped magnesium vanadate nitride, characterized in that: Gold-doped magnesium vanadate nitride is prepared by nitridation using a chemical solution method and an argon / ammonia mixed atmosphere, comprising the following steps: (1) Dissolve 5 mmol of soluble vanadate and 20 mmol of oxalic acid in 50 mL of distilled water, labeled as solution A. (2) Disperse 0.01-0.05 mmol of haloauric acid, 3 mmol of soluble magnesium salt, and 9 mmol of oxalic acid in 30 mL of organic solvent, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 120-180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180-200 °C for 8-10 h, wash with ethanol 3-5 times, filter, and dry in a vacuum oven at 60-80 °C for 20-24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 500-700°C and 1-5°C min -1 calcined at a heating rate of 1 to 5 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate is heated at 700-750 °C for 1-2 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

2. The method for preparing gold-doped magnesium vanadate nitride according to claim 1, wherein: The vanadium oxysalt is one of sodium vanadate, potassium vanadate and lithium vanadate or a combination thereof.

3. The method for preparing gold-doped magnesium vanadate nitride according to claim 1, wherein: The haloauric acid is one of chloroauric acid and bromoauric acid or a combination thereof.

4. The method for preparing gold-doped magnesium vanadate nitride according to claim 1, wherein: The magnesium salt is one of magnesium acetate, magnesium nitrate and magnesium chloride or a combination thereof.

5. The method for preparing gold-doped magnesium vanadate nitride according to claim 1, wherein: The organic solvent is one of ethanol, methanol or propanol or a combination thereof.

6. The method for preparing gold-doped magnesium vanadate nitride according to any one of claims 1 to 5, characterized in that: Prepare as follows: (1) Dissolve 5 mmol sodium vanadate and 20 mmol oxalic acid in 50 mL distilled water, labeled solution A. (2) Disperse 0.01 mmol of chloroauric acid, 3 mmol of magnesium nitrate, and 9 mmol of oxalic acid in 30 mL of organic solvent propanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 120 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180 °C for 10 h, wash with ethanol five times, filter, and dry in a vacuum oven at 80 °C for 20 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 500 °C and 1 °C min -1 The mixture was calcined at a heating rate of 500 nm for 5 h to obtain gold-doped magnesium vanadate. (5) Gold-doped magnesium vanadate was heated at 750 °C for 1 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

7. The method for preparing gold-doped magnesium vanadate nitride according to any one of claims 1 to 5, characterized in that: Prepare as follows: (1) Dissolve 5 mmol potassium vanadate and 20 mmol oxalic acid in 50 mL distilled water, labeled solution A. (2) Disperse 0.03 mmol of chloroauric acid, 3 mmol of soluble magnesium salt, and 9 mmol of oxalic acid in 30 mL of organic solvent propanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 200 °C for 8 h, wash with ethanol three times, filter, and dry in a vacuum oven at 60 °C for 24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 700 °C and 2 °C min -1 calcined at a heating rate of 2 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate was heated at 750 °C for 1 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

8. The method for preparing gold-doped magnesium vanadate nitride according to any one of claims 1 to 5, characterized in that: Prepare as follows: (1) Dissolve 5 mmol of lithium vanadate and 20 mmol of oxalic acid in 50 mL of distilled water, labeled as solution A; (2) Disperse 0.05 mmol of bromoauric acid, 3 mmol of soluble magnesium chloride, and 9 mmol of oxalic acid in 30 mL of the organic solvent methanol, labeled as solution B. Slowly add solution A dropwise to solution B to form solution C. (3) Add 12 mmol of ammonium fluoride to solution C and stir for 180 min to form a transparent solution. Then, transfer solution C to a 100 mL Teflon-lined autoclave, heat at 180 °C for 10 h, wash with ethanol five times, filter, and dry in a vacuum oven at 80 °C for 24 h to obtain a gold-doped magnesium vanadate precursor. (4) The gold-doped magnesium vanadate precursor was heated in a tube furnace at 600 °C and 3 °C min -1 calcined at a heating rate of 3 h to obtain gold-doped magnesium vanadate; (5) Gold-doped magnesium vanadate was heated at 700 °C for 2 h in an Ar / NH3 mixed atmosphere to obtain gold-doped magnesium vanadate nitride.

9. A gold-doped magnesium vanadate nitride, characterized in that Prepared according to any one of claims 1 to 8.

10. Use of the gold-doped magnesium vanadate nitride material according to claim 9 in battery materials.