CN102923779B - Preparation method of flower-shaped spherical Bi2MoO6 microcrystal - Google Patents

Abstract

The invention provides a preparation method of flower-shaped spherical Bi2MoO6 microcrystal. The preparation method comprises the following steps: adding sodium molybdate dehydrate into deionized water to obtain a solution A; respectively adding bismuth nitrate pentahydrate and PVP (polyvinyl pyrrolidone) into the deionized water to obtain a solution B; adding the solution A into the solution B to obtain a precursor solution C; dissolving chitosan solution in concentrated acetic acid solution to obtain a solution D; uniformly mixing the solution C with the solution D to obtain a solution E; pouring the solution E into a microwave hydrothermal reaction kettle, and placing the reaction kettle into an MDS-8 type microwave hydrothermal reaction instrument; naturally cooling to room temperature after the reaction is finished; opening the microwave hydrothermal reaction kettle, collecting the product by centrifugation, and then washing with deionized water and anhydrous ethanol respectively; drying in an electrothermal blowing dry box to obtain the final product flower-shaped spherical Bi2MoO6 microcrystal. The preparation method provided by the invention adopts a simple microwave hydrothermal preparation process and uses the PVP as a template agent to prepare the flower-shaped spherical Bi2MoO6 microcrystal. The reaction method has the advantages that the reaction period is short, the reaction temperature is low, the energy consumption is greatly reduced, the cost is saved, the operation is simple, and has no pollution to environment.

Description

A kind of flower ball-shaped Bi 2moO 6the preparation method of crystallite

Technical field

The present invention relates to a kind of Bi ₂moO ₆the preparation method of crystallite, particularly a kind ofly can prepare flower ball-shaped Bi fast ₂moO ₆the method of crystallite.

Background technology

Therefore along with social development, environmental pollution is more and more serious, and water is the necessary condition of human survival, becomes current important topic for sewage disposal, photocatalyst due to can degrade and water of decomposition in the pollutent parent that firmly gets investigator look at.In the novel photocatalyst having been found that, bismuth-containing visible light catalyst is such as Bi ₂inNbO ₇, Bi ₂wO ₆and BiVO ₄etc., because its special crystalline structure has shown higher visible light catalysis activity, firmly get investigator's concern.The chemical general formula of bismuth molybdate is Bi ₂o ₃nMoO ₃, the n=3 here, 2 or 1, be associated with it respectively do for oneself α-, β-, γ-phase.This γ-phase (Bi ₂moO ₆) be a kind of typical Aurivillius structure.Result of study shows, under the irradiation of visible ray, and Bi ₂moO ₆can form a kind of photocatalyst and solar energy converting material of excellence, it can decompose with degradation water in organic compound.As a kind of important semiconductor material, Bi ₂moO ₆due to its excellent electricity and optical property, be widely used in solar cell, gas sensor, ionophore, the fields such as catalyzer.

The preparation method of bismuth molybdate mainly contains solid reaction process [S.Williams at present, M.Puri, A.J.Jacobson, C.A.Mims, Propene oxidation on substituted 2:1 bismuth molybdates andvanadates[J] .Catal.Today., 1997,37:43-49.], scorification [Kudo A, Hijii S.H ₂or O ₂evolution from Aqueous Solutions on Layered Oxide Photocatalysts Consisting ofBi ³⁺with 6s ²configuration and d ⁰transition Metal Ions[J] .Chem.Lett., 1999,10:1103-1104.] and hydrothermal method [Shi Y H, Feng S H, Cao C S.Hydrothermal Synthesis andCharacterization of Bi ₂moO ₆and Bi ₂wO ₆[J] .Mater.Lett., 2000,44:215-218.] etc.Yet these method majorities need high-temperature calcination, numerous deficiencies such as product pattern be difficult to be controlled and the reaction times is long.

Summary of the invention

The object of this invention is to provide a kind of speed of response fast, generated time is short, and reaction once completes, and does not need post-processed, and with low cost, productive rate is higher, free of contamination flower ball-shaped Bi ₂moO ₆the preparation method of crystallite.

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

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.050mol/L-0.150mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.100mol/L-0.300mol/L, the solution B that PVP concentration is 0.04mol/L-0.20mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: (0.95～1.05), and constantly stir, form precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 2-4;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.10-0.30mol/L; By solution C with solution D by 100: the volume ratio of (2～5) mixes to obtain solution E;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 50-70%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 140 ℃-180 ℃, and the reaction times is controlled at 30min-90min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

The present invention adopts simple microwave-hydrothermal method preparation technology, take PVP as template, has prepared flower ball-shaped Bi ₂moO ₆crystallite.The method reaction time is short, temperature of reaction is low, greatly reduces energy consumption, has saved cost, and simple to operate, environmentally safe.

Useful effect:

1) Bi that the present invention makes ₂moO ₆crystallite is flower ball-shaped, complete shape and appearance, and by controlling temperature of reaction and time, can control the size of ball.

2) raw material required for the present invention is easy to get, and reaction once completes, and reaction time is short, simple to operate, and cost is lower, and productive rate is higher, and purity is high and pollution-free.

Accompanying drawing explanation

Fig. 1 is the flower ball-shaped Bi of embodiment 1 preparation ₂moO ₆the X-ray diffraction of crystallite (XRD) collection of illustrative plates.

Fig. 2 is the flower ball-shaped Bi of embodiment 1 preparation ₂moO ₆the scanning electron microscope of crystallite (SEM) photo is (b) and (c) enlarged view of (a).

Embodiment

Embodiment 1:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.150mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.28mol/L, the solution B that PVP concentration is 0.18mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: 1, and constantly stirs, and forms precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 3;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.2mol/L; Solution C is mixed to obtain to solution E with solution D by the volume ratio of 100:3.5;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 50%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 160 ℃, and the reaction times is controlled at 40min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

By the flower ball-shaped Bi of gained ₂moO ₆rigaku D/max2000PCX-x ray diffractometer x analytic sample for crystallite, product is the rhombic system Bi that JCPDS is numbered 72-1524 as seen from Figure 1 ₂moO ₆crystallite.

This sample is observed by the S-4800 type scanning electronic microscope that HIT produces, and the photo from Fig. 2 can be found out prepared Bi ₂moO ₆crystalline substance has special flower ball-shaped pattern, from its enlarged view, can find out that this flower ball-shaped is formed by many sheet structure self-assemblies.

Embodiment 2:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.08mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.168mol/L, the solution B that PVP concentration is 0.15mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: 0.95, and constantly stirs, and forms precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 2.5;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.25mol/L; Solution C is mixed to obtain to solution E with solution D by the volume ratio of 100:3;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 60%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 170 ℃, and the reaction times is controlled at 50min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

Embodiment 3:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.06mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.114mol/L, the solution B that PVP concentration is 0.1mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: 1.05, and constantly stirs, and forms precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 3.5;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.15mol/L; Solution C is mixed to obtain to solution E with solution D by the volume ratio of 100:2.5;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 60%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 180 ℃, and the reaction times is controlled at 30min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

Embodiment 4:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.05mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.1mol/L, the solution B that PVP concentration is 0.04mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: 1, and constantly stirs, and forms precursor solution C;

4) with NaOH or H NO ₃regulating the pH value of precursor solution C is 2;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.1mol/L; Solution C is mixed to obtain to solution E with solution D by the volume ratio of 100:2;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 65%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 140 ℃, and the reaction times is controlled at 90min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

Embodiment 5:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.1mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.3mol/L, the solution B that PVP concentration is 0.20mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: 1.05, and constantly stirs, and forms precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 4;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.3mol/L; Solution C is mixed to obtain to solution E with solution D by the volume ratio of 100:5;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 70%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 150 ℃, and the reaction times is controlled at 80min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

Claims (1)

1. a flower ball-shaped Bi ₂moO ₆the preparation method of crystallite, is characterized in that:

1) by analytically pure Sodium Molybdate Dihydrate (Na ₂moO ₄2H ₂o) join in deionized water, and constantly stir, being configured to concentration is the clear solution A of 0.050mol/L-0.150mol/L;

2) respectively by analytically pure five water Bismuth trinitrate (Bi (NO ₃) ₃5H ₂o) join in deionized water and constantly stir with PVP, make [Bi ³⁺] concentration is 0.100mol/L-0.300mol/L, the solution B that PVP concentration is 0.04mol/L-0.20mol/L;

3) A solution is slowly added in solution B, controlling Bi/Mo amount ratio is 2: (0.95～1.05), and constantly stir, form precursor solution C;

4) with NaOH or HNO ₃regulating the pH value of precursor solution C is 2-4;

Chitosan is dissolved in dense acetum to the chitosan solution D that compound concentration is 0.10-0.30mol/L; By solution C with solution D by 100: the volume ratio of (2～5) mixes to obtain solution E;

5) solution E is poured in microwave hydrothermal reaction kettle, compactedness is controlled at 50-70%; Then seal microwave hydrothermal reaction kettle, put it in MDS-8 type microwave hydrothermal reaction, hydrothermal temperature is controlled at 140 ℃-180 ℃, and the reaction times is controlled at 30min-90min, after reaction finishes, naturally cools to room temperature;

6) open microwave hydrothermal reaction kettle, product, by centrifugal collection, then adopts respectively deionized water and absolute ethanol washing, in electric drying oven with forced convection, at 80 ℃, is dried to obtain final product flower ball-shaped Bi ₂moO ₆crystallite.

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