Preparation method of m-phase vanadium dioxide nanopowder

Abstract

The invention discloses a preparation method for phase-M vanadium dioxide nanometre powder. The preparation method comprises the following steps: mixing polyhydric alcohol with a carbon chain length of 3 to 10 with monohydric alcohol with a carbon chain length of 1 to 5 in a volume ratio of 1: (6 to 15), so as to obtain a mixed alcohol solution; then adding quaternary ammonium salt with a carbon chain length of 1 to 16 in the mixed alcohol solution, so as to obtain electrolyte, wherein the concentration of quaternary ammonium salt in the electrolyte is 1-5 g / L; then using a vanadium metal block as an anode, using a platinum metal block or a vanadium metal block as a cathode, keeping a distance between the anode and the cathode to be 2 mm to 5 cm, placing the anode and the cathode in the electrolyte, and electrolysing for 1 to 3 hours under a voltage of 2 to 30 V, so as to obtain a reaction solution containing precipitates; then performing a solid-liquid treatment and a washing treatment on the reaction solution, so as to obtain an intermediate product; and after that, annealing the intermediate product for 1 to 3 hours at a temperature of 350 to 450 DEG C and under a pressure of 10 to 100 Pa, so as to prepare the target product with a particle size of 50 to 100 nm. The preparation method has the characteristics of being time-saving, energy-saving, environment-friendly, low in preparation cost, and easy to realize large-scale industrialized production.

Description

technical field [0001] The invention relates to a preparation method of nano powder, in particular to a preparation method of M-phase vanadium dioxide nano powder. Background technique [0002] Vanadium dioxide (VO 2 ) There are mainly 5 kinds of crystal structures - R-phase VO 2 , M-phase VO 2 , Phase A VO 2 , B-phase VO 2 and D phase VO 2 , where the M-phase VO 2 It is a temperature-induced phase change material. The phase transition temperature of single crystal is 68°C. With the phase transition, VO 2 The physical properties such as electrical conductivity, infrared light transmittance, resistivity and reflectivity will change suddenly, so that the M-phase VO 2 It has broad application prospects in the fields of intelligent temperature control films, thermistor materials, photoelectric switch materials, and infrared detection materials. Recently, in order to obtain the M-phase VO 2 , and developed a variety of preparation methods, such as sol-gel method, co-prec...

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Problems solved by technology

Recently, in order to obtain the M-phase VO 2 , and developed a variety of preparation methods, such as sol-gel method, co-precipitation method, hydrothermal method, etc., these methods have defects such as slow reaction, difficult control of product shape, high cost, and large pollution to varying degrees.

Although other methods are also used, such as a method for directly synthesizing M-phase vanadium dioxide nanoparticles by a liquid phase method published on August 1, 2012 by the Chinese invention patent application CN102616849A, the method first uses vanadium pentoxide and partial vanadium One or a mixture of two acid salts is used as a raw material, mixed with distilled water and stirred at 60-100°C to obtain a constant temperature vanadium suspension, and then the reducing agent is added dropwise to it and the reaction is continued for 1-6 hours to obtain the reaction Afterwards, the reaction product is centrifuged to obtain the precursor substance, and then the precursor substance is mixed with distilled water and then transferred to a reaction kettle for a hydrothermal reaction at a temperature of 220-260°C and a time of 24-72 hours, and finally , centrifuge the hydrothermal reactant, wash with distilled water and absolute ethanol for 2 to 4 times, and dry at 100°C for more than 12 hours to obtain M-phase vanadium dioxide nanoparticles; however, there are still time-consuming, energy-consuming, and difficult Insufficiency of large-scale industrial production

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