阅读说明：本技术 一种五氧化二铌纳米带的制备方法 (preparation method of niobium pentoxide nanoribbon ) 是由 庄文生 温尚龙 陈欣义 于 2019-09-23 设计创作，主要内容包括：本发明公开了一种五氧化二铌纳米带的制备方法,包括以下步骤：1)将五氯化铌和氨水混合均匀,得到混合液；2)将混合液加入水热反应釜,进行水热反应,冷却,得到水热反应产物；3)对水热反应产物进行固液分离,再对分离得到的固体产物进行洗涤、干燥和煅烧。本发明通过水热法制备五氧化二铌纳米带,操作简单、产量高、耗时短,可以极大地提高生产效率,有助于推动五氧化二铌纳米带的大规模生产和大面积推广应用。(the invention discloses a preparation method of a niobium pentoxide nanobelt, which comprises the following steps: 1) uniformly mixing niobium pentachloride and ammonia water to obtain a mixed solution; 2) adding the mixed solution into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to obtain a hydrothermal reaction product; 3) and carrying out solid-liquid separation on the hydrothermal reaction product, and then washing, drying and calcining the solid product obtained by separation. The method for preparing the niobium pentoxide nanoribbon by the hydrothermal method is simple to operate, high in yield and short in time consumption, can greatly improve the production efficiency, and is beneficial to promoting large-scale production and large-area popularization and application of the niobium pentoxide nanoribbon.)

1. a preparation method of niobium pentoxide nanobelts is characterized by comprising the following steps: the method comprises the following steps:

1) uniformly mixing niobium pentachloride and ammonia water to obtain a mixed solution;

2) Adding the mixed solution into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to obtain a hydrothermal reaction product;

3) and carrying out solid-liquid separation on the hydrothermal reaction product, and then washing, drying and calcining the solid product obtained by separation to obtain the niobium pentoxide nanobelt.

2. The method of claim 1, wherein: in the step 1), the mass-to-volume ratio of niobium pentachloride to ammonia water is (0.1-1) g: (40-60) mL.

3. The production method according to claim 1 or 2, characterized in that: the mass percentage concentration of the ammonia water in the step 1) is 15-25%.

4. The method of claim 1, wherein: the temperature of the hydrothermal reaction in the step 2) is 160-200 ℃, and the time is 9-18 h.

5. The production method according to claim 1, 2 or 4, characterized in that: and 2) the hydrothermal reaction kettle is a high-temperature high-pressure reaction kettle with a polytetrafluoroethylene or glass lining.

6. The method of claim 1, wherein: and in the step 3), washing is carried out for multiple times by using deionized water and absolute ethyl alcohol sequentially.

7. The production method according to claim 1 or 2 or 4 or 6, characterized in that: and 3) drying at the temperature of 50-70 ℃ for 5-48 h.

8. The production method according to claim 1 or 2 or 4 or 6, characterized in that: and 3) calcining at the temperature of 450-600 ℃ for 0.5-2 h.

9. The method of claim 8, wherein: and 3) the calcination is carried out in a muffle furnace.

Technical Field

The invention relates to a preparation method of a niobium pentoxide nanobelt, belonging to the technical field of inorganic nano materials.

Background

the lithium ion battery has high output voltage, large volume energy density and power density, small self-discharge rate, long cycle service life, no toxicity, environmental protection and high specific capacity, is the most important and most advanced secondary battery at present, and becomes the main energy supply mode of portable electronic products.

However, most of the lithium ion batteries have certain potential safety hazards, mainly because lithium dendrites may be generated in the use process of the lithium ion batteries to pierce through battery diaphragms, so that internal short circuits of the batteries are caused, and finally catastrophic accidents are caused.

Lithium titanate (Li)₄Ti₅O₁₂) And niobium pentoxide (Nb)₂O₅) The lithium ion battery is two common electrode materials, can effectively avoid the generation of lithium dendrites, and has good application prospect.

Lithium titanate has a high voltage platform (1.7V), can avoid the generation of lithium dendrites, has high theoretical specific capacity (175mAh/g) and actual capacity (160mAh/g), has good cycle performance and rate capability, and is a commercial electrode material, but because lithium titanate contains metallic lithium, the production and manufacturing cost is high, and the large-scale application of the lithium titanate is limited.

Niobium pentoxide has high intercalation/deintercalation lithium potential (1.2-1.8 Vvs. Li/Li)⁺) The lithium ion battery cathode material is higher than the reaction forming potential (0.75V) of a Solid Electrolyte Interface (SEI) film, can inhibit the formation of lithium dendrites, has better safety, has a theoretical capacity of 201mAh/g, is higher than lithium titanate, is an ideal lithium ion battery cathode material, but has poor conductivity of niobium pentoxide and still needs to be improved in rate capability.

The niobium pentoxide with the nano-belt-shaped structure is beneficial to shortening the diffusion distance of lithium ions, so that the rate capability of the niobium pentoxide can be obviously improved on the premise of ensuring the safety performance, and the niobium pentoxide nano-belt is a power lithium ion battery cathode material with good safety performance and high rate capability, but the existing niobium pentoxide nano-belt preparation method generally has the defects of complex operation, low yield, long time consumption and the like, and limits the large-scale production and large-area application of the niobium pentoxide nano-belt.

Therefore, there is a need to develop a method for preparing niobium pentoxide nanobelt with simple operation, high yield and short time consumption.

disclosure of Invention

The invention aims to provide a preparation method of niobium pentoxide nanoribbons.

The technical scheme adopted by the invention is as follows:

A preparation method of niobium pentoxide nanoribbons comprises the following steps:

1) Uniformly mixing niobium pentachloride and ammonia water to obtain a mixed solution;

2) adding the mixed solution into a hydrothermal reaction kettle, carrying out hydrothermal reaction, and cooling to obtain a hydrothermal reaction product;

3) And carrying out solid-liquid separation on the hydrothermal reaction product, and then washing, drying and calcining the solid product obtained by separation to obtain the niobium pentoxide nanobelt.

Preferably, the mass-to-volume ratio of the niobium pentachloride to the ammonia water in the step 1) is (0.1-1) g: (40-60) mL.

Preferably, the mass percentage concentration (w/w) of the ammonia water in the step 1) is 15-25%.

Preferably, the temperature of the hydrothermal reaction in the step 2) is 160-200 ℃, and the time is 9-18 h.

Preferably, the hydrothermal reaction kettle in the step 2) is a high-temperature high-pressure reaction kettle with a polytetrafluoroethylene or glass lining.

preferably, the washing in step 3) is performed by using deionized water and absolute ethyl alcohol to wash for multiple times sequentially.

Preferably, the drying temperature in the step 3) is 50-70 ℃, and the time is 5-48 h.

Preferably, the calcining temperature in the step 3) is 450-600 ℃, and the time is 0.5-2 h.

Preferably, the calcination of step 3) is carried out in a muffle furnace.

The invention has the beneficial effects that: the method for preparing the niobium pentoxide nanoribbon by the hydrothermal method is simple to operate, high in yield and short in time consumption, can greatly improve the production efficiency, and is beneficial to promoting large-scale production and large-area popularization and application of the niobium pentoxide nanoribbon.

Drawings

FIG. 1 is an SEM image of the niobium pentoxide nanoribbon of example 1.

FIG. 2 is an X-ray diffraction pattern of the niobium pentoxide nanoribbons of example 1.

FIG. 3 is a curve showing the charge and discharge performance test of the niobium pentoxide nanoribbon of example 1.

FIG. 4 is a graph showing the cycle performance test of the niobium pentoxide nanoribbons of example 1.

Fig. 5 is an SEM image of the niobium pentoxide nanoribbon in comparative example 1.

Fig. 6 is an SEM image of niobium pentoxide nanoplates in comparative example 2.

Fig. 7 is an SEM image of the niobium pentoxide nanoribbon in comparative example 3.

Fig. 8 is an SEM image of the niobium pentoxide nanoribbon in comparative example 4.

Fig. 9 is an SEM image of niobium pentoxide nanoplates in comparative example 5.

Detailed Description

the invention will be further explained and illustrated with reference to specific examples.