D-phase vanadium dioxide nano-star powder and preparation method thereof

A technology of vanadium dioxide nano and vanadium dioxide powder, which is applied in the field of D-phase vanadium dioxide nano star powder and its preparation, which can solve the problems of complicated process and unfavorable application, and achieve difficult agglomeration, low production cost, and easy preparation The effect of simple method

Active Publication Date: 2015-03-11
HEFEI INSTITUTES OF PHYSICAL SCIENCE - CHINESE ACAD OF SCI
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, both the product and its preparation method have shortcomings. First, although the phase transition temperature of the product can be adjusted to around room temperature, its size has reached the micron level, which is not conducive to practical application; secondly, the preparation Dopants need to be added during the process, resulting in a more complicated process

Method used

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  • D-phase vanadium dioxide nano-star powder and preparation method thereof
  • D-phase vanadium dioxide nano-star powder and preparation method thereof
  • D-phase vanadium dioxide nano-star powder and preparation method thereof

Examples

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Effect test

Embodiment 1

[0033] The concrete steps of preparation are:

[0034] Step 1: First, according to the weight ratio of 0.05:5, ammonium metavanadate was dissolved in deionized water and stirred for 0.5 h to obtain ammonium metavanadate aqueous solution. Then, 80wt% formic acid solution was added dropwise into the ammonium metavanadate aqueous solution under stirring to obtain a mixed solution with a pH value of 3.

[0035] In step 2, the mixed solution is placed in an airtight state, and reacted at 180° C. for 3 days to obtain a reaction solution. Then the reaction solution is subjected to solid-liquid separation, washing and drying in sequence; wherein, the solid-liquid separation process is centrifugation, the rotational speed and time of centrifugation are respectively 5000r / min and 10min, and the washing process is to use deionized water and ethanol to The separated solids were washed alternately for 3 times. During the cleaning, the solids were separated by centrifugation. The temperatu...

Embodiment 2

[0037] The concrete steps of preparation are:

[0038]Step 1: First, according to the weight ratio of 0.055:5, ammonium metavanadate was dissolved in deionized water and stirred for 0.6 h to obtain an ammonium metavanadate aqueous solution. Then, 83wt% formic acid solution was added dropwise into the ammonium metavanadate aqueous solution under stirring to obtain a mixed solution with a pH value of 2.5.

[0039] In step 2, the mixed solution is placed in an airtight state and reacted at 190° C. for 2.5 days to obtain a reaction solution. Then the reaction solution is subjected to solid-liquid separation, washing and drying in sequence; wherein, the solid-liquid separation process is centrifugation, the rotational speed and time of centrifugation are 6000r / min and 9min respectively, and the washing process is to use deionized water and ethanol to The separated solids were washed alternately for 3 times, and the solids were separated by centrifugation during cleaning. The tempe...

Embodiment 3

[0041] The concrete steps of preparation are:

[0042] Step 1: First, according to the weight ratio of 0.06:5, ammonium metavanadate was dissolved in deionized water and stirred for 0.75h to obtain ammonium metavanadate aqueous solution. Then, 85wt% formic acid solution was added dropwise to the ammonium metavanadate aqueous solution under stirring to obtain a mixed solution with a pH value of 2.

[0043] In step 2, the mixed solution is placed in an airtight state, and reacted at 200° C. for 2 days to obtain a reaction solution. Then the reaction solution is subjected to solid-liquid separation, washing and drying in sequence; wherein, the solid-liquid separation process is centrifugation, the rotational speed and time of centrifugation are respectively 7500r / min and 7.5min, and the washing process is to use deionized water and ethanol The separated solid matter was alternately washed 4 times, the solid matter was separated by centrifugation during washing, and the temperatu...

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Abstract

The invention relates to D-phase vanadium dioxide nano-star powder and a preparation method thereof. The powder is D-phase vanadium dioxide nano-star powder with a shape of pentagram or hexagram flat particles with the flat thickness of 30-60nm and the flat diameter of 60-100nm. Conical star point base thickness of the pentagram or hexagram particle is same with the flat thickness, conical star point base width is 30-60nm, and star point length is 70-100nm. The preparation method comprises the following steps: ammonium metavanadate is dissolved in deionized water, and the mixture is stirred, such that an ammonium metavanadate water solution is obtained; a formic acid solution is dropped into the ammonium metavanadate water solution being stirred, such that a mixed liquid with a pH value of 1-3 is obtained; the mixed liquid is set in a sealed state, and is allowed to react for 1-3d under a temperature of 180-220 DEG C, such that a reaction liquid is obtained; and the reaction liquid is sequentially subjected to solid-liquid separation, washing and drying, such that a target product is obtained. With subsequent heat treatment, obtained VO2(M) nano-star powder can be widely applied in the fields of intelligent temperature-control films, thermistor materials, photoelectric switch materials, infrared detection materials, gas sensors, storage materials, and the like.

Description

technical field [0001] The invention relates to a nano-star powder and a preparation method thereof, in particular to a D-phase vanadium dioxide nano-star powder and a preparation method thereof. Background technique [0002] The oxide system of vanadium is complex, and vanadium ions have various valence states, including +2, +3, +4, +5 and mixed valence states. Among them, the tetravalent oxide vanadium dioxide (VO 2 ) There are many isomers, such as: VO 2 (R), VO 2 (M), VO 2 (A), VO 2 (B), VO 2 (C) and VO 2 (D). Existing research results show that the M-phase VO 2 It is a metal oxide material with reversible phase transition characteristics. When the temperature is higher than Tc = 68 ° C, a structural phase transition from a low-temperature monoclinic phase to a high-temperature tetragonal rutile phase occurs. At the same time, the electrical conductivity, infrared light transmittance, and resistivity The physical properties such as reflectivity and reflectivity w...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C01G31/02B82Y30/00B82Y40/00
CPCC01G31/02C01P2002/72C01P2002/88C01P2004/03C01P2004/04C01P2004/22C01P2004/64
Inventor 钟莉李明李广海
Owner HEFEI INSTITUTES OF PHYSICAL SCIENCE - CHINESE ACAD OF SCI
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