CN102936043B - Method for synthesizing hexagonal columnar MoO3 microcrystalline in core-shell structure through hydrothermal method - Google Patents

Abstract

The invention discloses a method for synthesizing hexagonal columnar MoO3 microcrystalline in a core-shell structure through a hydrothermal method. The method includes adding ammonium molybdate into deionized water to obtain a solution A; preparing a toluenesulfonate sodium solution B and an ammonium oxalate solution C respectively; mixing the solutions A, B and C to obtain a solution D; adding the solution D into a hydrothermal kettle, placing in an electrothermal thermostatic blast drying oven for reaction, and cooling naturally to the room temperature after the reaction is finished; and opening the hydrothermal kettle, taking out a product, washing with the deionized water and performing centrifugal separation, then washing with absolute ethyl alcohol and performing centrifugal separation, and drying in an electrothermal vacuum drying oven to obtain the hexagonal columnar MoO3 microcrystalline in the core-shell structure after repeated washing with the deionized water and the absolute ethyl alcohol sequentially. The hexagonal phase MoO3 microcrystalline prepared through the method and provided with special forms on the surface is large in relative surface area, so that high chemical activity, good photocatalysis and the like are provided; and microcrystalline grains are complete in development, high in purity, good in crystallinity and even in distribution.

Description

The nucleocapsid structure MoO of the synthetic hexagonal columnar of a kind of hydrothermal method 3the method of crystallite

Technical field

The present invention relates to a kind of nucleocapsid structure MoO for preparing hexagonal columnar ₃the method of crystallite, particularly a kind of hydrothermal method preparation table mask has the hexagonal columnar MoO of specific form ₃the method that micron is brilliant.

Background technology

MoO ₃be a kind of pale yellow powder, easily deliquescence, water insoluble, is soluble in ammoniacal liquor, highly basic and strong acid.MoO ₃there is electrochromism, photochromic, photocatalytic degradation and gas-sensitive property etc., aspect many functional materialss such as display equipment, sensor, intelligent window and battery electrode, having broad application prospects.MoO ₃there are three kinds of crystal formations: the orthogonal phase MoO of stable state ₃(α-MoO ₃), metastable monoclinic phase MoO ₃(β-MoO ₃) and metastable six side's phase MoO ₃(h-MoO ₃).Wherein, h-MoO ₃the one of the molybdic oxide steady phase that is situated between, than α-MoO ₃there is renewal, more superior physical and chemical activity.Find be situated between steady phase molybdic oxide simply, synthetic method effectively and rapidly, explore MoO ₃theory aspect photochemical catalysis and application all will be of practical significance more.

About six side's phase MoO ₃report has: ［ the Guo J D such as 995 years Whttingham, Zavzlij P, Whittingham M S.Metastable hexagonal molybdates:hydrothermal preparation structure and reactivity ［ J ］ .Solid.State.Chem, 1995,117:323-332. ］ report the h-MoO containing positive monovalent ion ₃; 2005 and 2007, Zheng Huagui taught ［ Song J M, Wang X, Ni X M, et al.Preparation of hexagonal-MoO ₃and electrochemical properties of lithium intercalation into the oxide ［ J ］ .Mater.Res.Bul, 2005,40:1751-1756.Song J M, Ni X M, Gao L S, et al.Synthesis ofmetastableh-MoO ₃by Simple Chemical Precipitation ［ J ］ .Mater.Chem.Phy, 2007,102:245-248. ］ on the basis of Komaba, improve synthetic method, successfully prepare h-MoO ₃; ［ Chu X F, Liang S M, Sun W Q, Zhang W B, the et al.Trimethylaminesensing properties of sensors based on MoO such as Chu Xiangfeng ₃microrods ［ J ］ .Sensors and Actuators B:Chemical, 2010,148:399-403. ］ be that raw material has synthesized h-MoO3 micron bar with ammonium molybdate, urea and sodium hydroxide, it has good gas sensing property as sensor; [S.R.Dhage, M.S.Hassan, O.-Bong Yang, the Lowtemperature fabrication of hexagon shaped h-MoO such as S.R.Dhage in 2009 ₃nanorods and its phase transformation ［ J ］ .Materials Chemistry and Physics, 2009,114:511-514] by ammonium molybdate, urea, sodium lauryl sulphate has been synthesized six side's phase h-MoO by the method for ultrasound probe at 70 ℃ ₃nanometer rod.

Summary of the invention

The object of the present invention is to provide a kind of equipment, raw material simple, process is held the nucleocapsid structure MoO of the synthetic hexagonal columnar of manageable hydrothermal method ₃the method of crystallite.The nucleocapsid structure MoO of the hexagonal columnar of making by preparation method of the present invention ₃crystallite has that purity is high, chemically reactive is high, have the features such as the performances such as good photochemical catalysis and high crystallization homogeneity.

For achieving the above object, the technical solution used in the present invention is as follows:

1) by analytical pure ammonium molybdate ((NH ₄) ₆mo ₇o ₂₄4H ₂o) join deionized water for stirring and make the ammonium molybdate solution that concentration is 0.02～0.09mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 2.0～5.0 must solution A;

3) the oxalic acid ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.005～0.009mol/L respectively and concentration are 0.01～0.05mol/L;

Solution A, solution B and solution C are pressed to 100:(5-10): volume ratio (2-5) is mixed, and stirs 12-24h and obtains solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 55～75%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 200～360 ℃, reacts 24～72 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 60～80 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

Useful effect:

1) surface of preparing due to the present invention has six side's phase MoO of specific form ₃the brilliant relative surface area of micron is larger, has higher chemically reactive, has the performances such as better photochemical catalysis;

2) gained surface has the hexagonal columnar MoO of specific form ₃that micron Jingjing grain is grown is complete, purity is higher, crystallinity is better and be evenly distributed;

3) owing to once completing in water heating kettle, do not need later stage thermal treatment, processing unit is simple; Can use more cheap raw material, and productive rate is higher, reaction time is short, and cost is low;

4) prepared surface has the hexagonal columnar MoO of specific form ₃crystallite shows certain oriented growth trend.

Accompanying drawing explanation

Fig. 1 is hexagonal columnar MoO prepared by the present invention ₃the SEM collection of illustrative plates of nucleocapsid structure crystallite.

Embodiment

Embodiment 1:

1) by analytical pure ammonium molybdate ((NH ₄) ₆mo ₇o ₂₄4H ₂o) join deionized water for stirring and make the ammonium molybdate solution that concentration is 0.02mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 2.0 must solution A;

3) the oxalic acid ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.005mol/L respectively and concentration are 0.01mol/L;

Solution A, solution B and solution C are pressed to the volume ratio of 100:5:2 and mix, stir 12-24h and obtain solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 55%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 200 ℃, reacts 72 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 60 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

Embodiment 2:

1) by analytical pure ammonium molybdate ((NH ₄) ₆mo ₇o ₂₄4H ₂o) join deionized water for stirring and make the ammonium molybdate solution that concentration is 0.04mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 3.0 must solution A;

3) the oxalic acid ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.006mol/L respectively and concentration are 0.02mol/L;

Solution A, solution B and solution C are pressed to the volume ratio of 100:6:3 and mix, stir 12-24h and obtain solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 60%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 260 ℃, reacts 60 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 70 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

Embodiment 3:

1) by analytical pure ammonium molybdate ((NH ₄) ₆mo ₇o ₂₄4H ₂o) join deionized water for stirring and make the ammonium molybdate solution that concentration is 0.09mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 4.0 must solution A;

3) the oxalic acid ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.007mol/L respectively and concentration are 0.03mol/L;

Solution A, solution B and solution C are pressed to the volume ratio of 100:8:4 and mix, stir 12-24h and obtain solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 70%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 300 ℃, reacts 40 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 70 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

Embodiment 4:

1) by analytical pure ammonium molybdate ((NH ₄) ₆mo ₇o ₂₄4H ₂o) join deionized water for stirring and make the ammonium molybdate solution that concentration is 0.07mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 5.0 must solution A;

3) the oxalic acid ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.009mol/L respectively and concentration are 0.05mol/L;

Solution A, solution B and solution C are pressed to the volume ratio of 100:10:5 and mix, stir 12-24h and obtain solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 75%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 360 ℃, reacts 24 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 80 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

As can be seen from Figure 1, the MoO of preparation ₃crystallite has obvious nucleocapsid structure, and skin is hexagonal columnar shell, and internal layer is MoO ₃cylindric crystallite.Whole nucleocapsid structure diameter is 25 μ m left and right.

Claims (1)

1. the nucleocapsid structure MoO of the synthetic hexagonal columnar of hydrothermal method ₃the method of crystallite, is characterized in that:

1) by analytically pure (NH ₄) ₆mo ₇o ₂₄4H ₂o joins deionized water for stirring and makes the ammonium molybdate solution that concentration is 0.02～0.09mol/L;

2) adopting maleic acid solution to regulate the pH value of ammonium molybdate solution is 2.0～5.0 must solution A;

3) the ammonium oxalate solution C that the toluenesulfonic acid sodium salt solution B that compound concentration is 0.005～0.009mol/L respectively and concentration are 0.01～0.05mol/L;

Solution A, solution B and solution C are pressed to 100:(5-10): volume ratio (2-5) is mixed, and stirs 12-24h and obtains solution D;

4) solution D is poured in water heating kettle, compactedness is controlled at 55～75%, then seals water heating kettle, puts it in electric heating constant-temperature blowing drying box, and controlling hydrothermal temperature is 200～360 ℃, reacts 24～72 hours, after reaction finishes, naturally cools to room temperature;

5) open water heating kettle, take out deionized water wash centrifugation for product, with absolute ethanol washing centrifugation, the electric vacunm drying case inner drying that adopts successively deionized water and dehydrated alcohol repeated washing to be placed on 60～80 ℃ for 4～6 times obtains the MoO of nucleocapsid structure again ₃hexagonal columnar crystallite.

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