Method for preparing nano vanadium dioxide by reverse hydrolytic precipitation

A technology of hydrolysis precipitation and vanadium dioxide, applied in vanadium oxide, nanotechnology and other directions, can solve the problems of good uniformity, the precursor is not easy to control the dispersibility and uniformity, and it is difficult to obtain the crystallinity, etc., to achieve good crystallinity, Easy to promote and apply in industrialization, easy to operate

Inactive Publication Date: 2021-01-26
CHENGDU ADVANCED METAL MATERIALS IND TECH RES INST CO LTD
View PDF16 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved by the present invention is: the preparation of vanadium dioxide by the existing chemical precipitation method is difficult to c

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing nano vanadium dioxide by reverse hydrolytic precipitation
  • Method for preparing nano vanadium dioxide by reverse hydrolytic precipitation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Measure 500ml of sodium hydroxide solution with a concentration range of 300g / L, and add VOSO dropwise to it during rapid stirring 4 When the solution reaches a pH of 7, centrifuge and alternately wash 6 times with deionized water and absolute ethanol, dry the washed solid product at 60°C for 12 hours, and grind to obtain a gray-black powder. Take 0.5g of the powder and add it to 60ml with a volume fraction of 50 % ethanol solution, placed in a high-temperature and high-pressure reactor, hydrothermally reacted at 200 ° C for 24 hours, cooled to room temperature after the reaction was completed, and centrifuged to obtain VO 2 Powder.

[0029] figure 1 for the VO 2 The XRD spectrum of the powder shows that the product is M phase, figure 2 for the VO 2 SEM image of the powder.

Embodiment 2

[0031] Measure 500ml of sodium hydroxide solution with a concentration range of 450g / L, and add VOSO dropwise to it during rapid stirring 4 When the solution reaches a pH of 8, centrifuge and alternately wash 6 times with deionized water and absolute ethanol, dry the washed solid product at 60°C for 12 hours, and grind to obtain a gray-black powder. Take 3.0 g of the powder and add it to 75 ml with a volume fraction of 50 % ethanol solution, placed in a high-temperature and high-pressure reactor, hydrothermally reacted at 230°C for 18h, cooled to room temperature after the reaction was completed, and centrifuged to obtain VO 2 target product.

Embodiment 3

[0033] Measure 500ml of sodium hydroxide solution with a concentration range of 600g / L, and add VOSO dropwise to it during rapid stirring 4When the solution reaches a pH of 8.5, centrifuge and alternately wash 6 times with deionized water and absolute ethanol, dry the washed solid product at 60°C for 12 hours, and grind to obtain a gray-black powder. Take 5.0 g of the powder and add it to 90 ml with a volume fraction of 50 % ethanol solution, placed in a high-temperature and high-pressure reactor, hydrothermally reacted at 260°C for 12 hours, cooled to room temperature after the reaction was completed, and centrifuged to obtain VO 2 target product.

[0034] As can be seen from the results of the examples, the present invention only adopts the method of reverse precipitation to prepare VO by changing the dropping method of chemical precipitation. 2 , through a large number of repeated experiments, it is determined that the end point of the addition is when the pH value of the ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention belongs to the technical field of preparation of vanadium dioxide, and particularly relates to a method for preparing nano vanadium dioxide through reverse hydrolytic precipitation. Aiming at the problem that nano vanadium dioxide with high crystallinity, good homogeneity and small granularity is difficult to obtain when vanadium dioxide is prepared by an existing chemical precipitation method, the invention provides a method for preparing nano vanadium dioxide by reverse hydrolytic precipitation, which comprises the following steps: a, taking a sodium hydroxide solution, and dropwise adding a tetravalent vanadium solution while stirring until the pH value of the solution is 7-8.5; b, conducting centrifuging, washing, drying and grinding to obtain precursor powder; and c, adding an ethanol solution, carrying out hydrothermal reaction for 12-24 hours, conducting cooling to room temperature, and conducting centrifuging and separating to obtain M-phase VO2 powder. The methodis simple in process, convenient to operate and low in preparation cost, a large amount of vanadium dioxide can be rapidly prepared, VO2 has the advantages of being high in purity, uniform in particle size distribution and good in crystallinity, and VO2 can be widely applied to the fields of intelligent windows, optoelectronic switches, thermistors and the like.

Description

technical field [0001] The invention belongs to the technical field of vanadium dioxide preparation, and in particular relates to a method for preparing nano vanadium dioxide by reverse hydrolysis precipitation. Background technique [0002] Chemical precipitation and hydrothermal method are the two most commonly used methods for liquid phase preparation of nano-powder. Chemical precipitation mainly uses tetravalent vanadium source. Under the action of precipitant, hydrolysis and precipitation occur to obtain vanadium hydroxide or basic oxygen carbonate Vanadium precursor, and then crystallize the precursor to obtain the target product. There are two main ways of crystallization, one is through high temperature heat treatment, which often has the problems of high energy consumption, product sintering, and poor uniformity; the other is hydrothermal Crystallization, using the advantages of hydrothermal reaction, can produce nano powder with uniform particle size and good cryst...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C01G31/02B82Y40/00
CPCB82Y40/00C01G31/02C01P2002/72C01P2004/03C01P2004/62
Inventor 刘波彭穗李道玉姚洁
Owner CHENGDU ADVANCED METAL MATERIALS IND TECH RES INST CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap