CN100567411C - A kind of preparation method of zinc sulfide nanometer material modified by silicon oxide - Google Patents

Abstract

A kind of preparation method of silica modified zinc sulfide nano-material belongs to the inolrganic chemicals technical field, is specifically related to the preparation method of zinc sulfide nano-material.The present invention is the zinc source with the zinc acetate, is the silicon source with water glass or tetraethoxy, is the sulphur source with sodium sulphite, adopts sol-gel-hydrothermal crystallizing reaction process to prepare silica modified zinc sulfide nano-material.Prepared silica modified zinc sulfide nano-material, silicon oxide mainly is coated on the surface of zinc sulphide.Preparation method of the present invention is simple, easy to operate, be suitable for scale operation.Prepared silica modified zinc sulfide nano-material uniform particles has satisfactory stability and monodispersity, can be with being in the fields such as fluorescent agent and optoelectronic equipment.

Description

A kind of preparation method of zinc sulfide nanometer material modified by silicon oxide

technical field

The invention belongs to the technical field of inorganic chemical materials, and in particular relates to a preparation method of zinc sulfide nanometer materials.

Background technique

Zinc sulfide nanomaterials have special photoelectric properties, and have a wide range of application values in the fields of luminescent materials, photoelectric devices and LED materials. The application performance of zinc sulfide nanomaterials depends on its particle size and surface physical and chemical properties. Generally, the physical and chemical properties of ZnS nanomaterials are very unstable and easily changed in applications, so it is very important to control their particle size and improve their stability. At present, the commonly used method to control the particle size of zinc sulfide nanomaterials and improve its stability is to use other substances for surface coating. Commonly used coatings include organic polymers and inorganic polymers (including silicon oxide and ceramics, etc.), and form nanocomposite structures with nanoparticles after coating. Among them, zinc sulfide nanocomposites modified by silicon oxide coating have shown more and more important application prospects in modern display and light-emitting technologies. However, at present, zinc sulfide inorganic coating is mainly embedded in silica glass or film by sol-gel method or laser deposition method, which is expensive and inconvenient to operate, so its application field is greatly restricted, and it is not conducive to Mass production.

Contents of the invention

The invention provides a method for preparing silicon oxide-modified zinc sulfide nanometer material, which is simple in operation, low in cost and suitable for large-scale production. The silicon oxide-modified zinc sulfide nanometer material prepared according to the invention has uniform particle size, good thermal stability and monodispersity.

The present invention uses zinc acetate as the zinc source, sodium silicate or tetraethyl orthosilicate as the silicon source, sodium sulfide as the sulfur source, and a sol-gel-hydrothermal reaction crystallization process to prepare silicon oxide-modified zinc sulfide nanomaterials.

Detailed technical scheme of the present invention is as follows:

A preparation method of silicon oxide modified zinc sulfide nanomaterials, comprising the following steps:

Step 1. Prepare silica hydrosol A.

Prepare a hydrochloric acid aqueous solution with a pH value of 1.0-3.0, then add a silicon source at 40-50° C., and stir until it is completely hydrolyzed to obtain a silicon oxide hydrosol A, which is ready for use.

Step 2. prepare zinc acetate aqueous solution B.

Dissolve zinc acetate in water and prepare zinc acetate aqueous solution B of 0.1-0.5 mol L ^-1 , then add ethylenediaminetetraacetic acid (EDTA) and stir, then adjust the pH value of the solution to 5.5-6.8 with ammonia water, and set aside .

Step 3. prepare sodium sulfide aqueous solution C.

Sodium sulfide is dissolved in water to prepare 0.1-0.5 mol·L ^-1 sodium sulfide aqueous solution C, ready for use.

Step 4. Preparation of zinc sulfide-silica gel.

Add the zinc acetate aqueous solution B obtained in step 2. into the silicon oxide hydrosol A obtained in step 1, and then drop into the obtained sodium sulfide aqueous solution C in step 3 to make it occur.

Zn ²⁺ +S ^2- →ZnS↓

The full reaction, and the formation of zinc sulfide-silica gel D.

Step 5. Hydrothermal crystallization reaction.

The zinc sulfide-silica gel D obtained in step 4. was transferred to a polytetrafluoroethylene-lined hydrothermal kettle, and the hydrothermal crystallization reaction was carried out at a temperature of 120-180° C. for 6-20 hours.

Step 6. Post-processing.

Filter, dry and grind the product after step 5. hydrothermal crystallization reaction to obtain the silicon oxide-modified zinc sulfide nanomaterial of the present invention.

It should be noted:

The silicon source adopted in step 1. can be sodium silicate or tetraethyl orthosilicate.

When drying the product after hydrothermal reaction crystallization in step 6., the temperature is preferably in the range of 105-130°C. If the temperature is too low, it is not conducive to the rapid removal of water; if the temperature is too high, the decomposition reaction of zinc sulfide may occur.

Step 2. The ethylenediaminetetraacetic acid itself that adds does not participate in reaction, but can be used for controlling the formation rate of zinc sulfide, plays the effect of stabilizer; The consumption of ethylenediaminetetraacetic acid is preferably the same as the zinc acetate of step 2. and step 3 . The sodium sulfide is an equimolar amount.

The principle of the present invention is to use silicon oxide to coat the surface of zinc sulfide nanoparticles to play the role of controlling the growth of zinc sulfide nanoparticles and improving the stability of zinc sulfide particles; adopting a hydrothermal process to crystallize zinc sulfide nanoparticles to avoid The decomposition of zinc sulfide caused by high-temperature crystallization is prevented, and the consequences of the growth of zinc sulfide nanoparticles and the decrease in specific surface area caused by the hard agglomeration of zinc sulfide nanoparticles are prevented.

Compared with the prior art, the present invention has the following advantages:

1. The preparation method of the present invention has low cost and simple reaction process, which is conducive to large-scale production of materials.

2, the silicon oxide modified zinc sulfide nanomaterial prepared by the present invention, X-ray diffraction analysis proves to have good sphalerite crystal form (as shown in Figure 2), transmission electron microscope proves particle diameter is not more than 50 nanometers (as shown in Figure 2) 3), uniform particles, good dispersion, excellent thermal stability and monodispersity.

3. The silica-modified zinc sulfide nanoparticles prepared in the present invention can be applied in a wide range of fields, such as fluorescent agents and photoelectric devices.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Fig. 2 is an X-ray diffraction pattern of silicon oxide-modified zinc sulfide nanoparticles prepared in the present invention with a mass ratio of 25%.

Fig. 3 is a high-resolution transmission electron micrograph of the 25% mass ratio silicon oxide-modified zinc sulfide nanoparticles prepared in this paper.

Detailed ways

Implementation Mode 1

Add 0.5ml tetraethyl orthosilicate to 50ml water, adjust the pH value to 2 with 2mol·L ^-1 hydrochloric acid solution, and hydrolyze with stirring at 45°C. Then, 60 ml of 0.2 mol·L ^-1 zinc acetate aqueous solution adjusted to pH 5.5 with ammonia water was added thereto. Under the condition of stirring, add the stabilizer ethylenediaminetetraacetic acid in an equimolar amount to zinc acetate to form a white turbid liquid. Then 60ml of 0.2mol·L ^-1 sodium sulfide aqueous solution was added dropwise, the stirred solution became slightly white and turbid, and continued stirring to form a white turbid solution. Then the cloudy solution was transferred to a polytetrafluoroethylene-lined hydrothermal kettle for hydrothermal crystallization reaction at 120°C for 20 hours. Filter the sample after hydroheating, wash it with water three times, then dry it at 110° C., and grind it to obtain silicon oxide-modified zinc sulfide nanoparticles with a mass ratio of SiO ₂ of 10%. The silicon oxide-modified zinc sulfide nanoparticle has an average diameter of 42 nanometers observed under an electron microscope, and the particles are spherical, uniform and monodisperse. XRD measurement results show that zinc oxide is sphalerite.

Implementation mode two

Add 1.152 g of sodium silicate to 100 ml of water, adjust the pH to 2 with 2 mol·L ^-1 hydrochloric acid solution, and stir and hydrolyze at 40°C. Then, 120 ml of 0.1 mol·L ⁻¹ zinc acetate aqueous solution adjusted to a liquid pH value of 6.0 with ammonia water was added thereto. Under the condition of stirring, add the stabilizer ethylenediaminetetraacetic acid in an equimolar amount to zinc acetate to form a white turbid liquid. Then 120 ml of 0.1 mol·L ^-1 sodium sulfide aqueous solution was dropped into the above clear solution, the stirring solution became slightly white and turbid, and continued stirring to form a white turbid solution. Then the cloudy solution was transferred to a polytetrafluoroethylene-lined hydrothermal kettle for hydrothermal crystallization at 150°C for 12 hours. Filter the sample after hydroheating, wash it with water for 3 times, then dry it at 105° C., and grind it to obtain SiO ₂ modified zinc sulfide nanoparticles with a mass ratio of 25%. The average diameter of the silicon oxide modified zinc sulfide nanoparticles observed under an electron microscope is 35 nanometers, the particles are spherical, uniform and monodisperse. XRD measurement results show that zinc sulfide is sphalerite.

Implementation Mode Three

Add 4.2ml tetraethyl orthosilicate to 50ml water, adjust the pH value to 2 with 2mol·L ^- 1 hydrochloric acid solution, and stir and hydrolyze at 50°C. Then, 60 ml of 0.2 mol·L ⁻¹ zinc acetate aqueous solution adjusted to pH 6.8 with ammonia water was added thereto. Under the condition of stirring, add the stabilizer ethylenediaminetetraacetic acid in an equimolar amount to zinc acetate to form a white turbid liquid. Then 60 ml of 0.2 mol·L ⁻¹ sodium sulfide aqueous solution was dropped into the above clear solution, the stirring solution became slightly white and turbid, and the stirring was continued to form a white turbid solution. Then the cloudy solution was transferred to a polytetrafluoroethylene-lined hydrothermal kettle for hydrothermal crystallization reaction at 180°C for 6 hours. Filter the sample after the hydrothermal reaction, wash it with water three times, then dry it at 130° C., and grind it to obtain silicon oxide-modified zinc sulfide nanoparticles with a mass ratio of 50%. The average diameter of the silicon oxide modified zinc sulfide nanoparticles observed under an electron microscope is 32 nanometers, the particles are spherical, uniform and monodisperse. XRD measurement results show that zinc sulfide is sphalerite.

Claims (4)

1, a kind of preparation method of silica modified zinc sulfide nano-material may further comprise the steps:

Step 1. preparation silicon oxide water-sol A:

Secure ph is 1.0～3.0 aqueous hydrochloric acid, adds the silicon source down at 40～50 ℃ then, stirs until complete hydrolysis, gets silicon oxide water-sol A, and is stand-by;

Step 2. preparation zinc acetate aqueous solution B:

Zinc acetate is dissolved in the water, is mixed with 0.1～0.5molL ^-1Zinc acetate aqueous solution B, add ethylenediamine tetraacetic acid (EDTA) then and stir, be 5.5～6.8 with ammoniacal liquor regulator solution pH value again, stand-by;

Step 3. formulating vulcanization sodium water solution C:

Sodium sulphite is soluble in water, be mixed with 0.1～0.5molL ^-1Sodium sulfide solution C, stand-by;

Step 4. preparation zinc sulphide-silica gel:

The zinc acetate aqueous solution B of step 2 gained is added among the silicon oxide water-sol A of step 1 gained, splash into the sodium sulfide solution C of step 3. gained again, make its generation

Zn ²⁺+S ^2-→ZnS↓

Abundant reaction, and form zinc sulphide-silica gel D;

The reaction of step 5. hydrothermal crystallizing:

Zinc sulphide-silica gel the D of step 4 gained is transferred in the teflon-lined water heating kettle, the following hydrothermal crystallizing reaction of 120～180 ℃ temperature condition 6～20 hours;

Step 6. aftertreatment:

To filter, dry, grind through the reacted product of step 5 hydrothermal crystallizing, promptly get silica modified zinc sulfide nano-material;

In the above-mentioned steps, the consumption of the ethylenediamine tetraacetic acid (EDTA) that described step 2 adds and the zinc acetate of described step 2 and the sodium sulphite of described step 3. are equimolar amount.

2, the preparation method of silica modified zinc sulfide nano-material according to claim 1 is characterized in that the silicon source of being adopted in the described step 1 is a water glass.

3, the preparation method of silica modified zinc sulfide nano-material according to claim 1 is characterized in that the silicon source of being adopted in the described step 1 is a tetraethoxy.

4, the preparation method of silica modified zinc sulfide nano-material according to claim 1 is characterized in that, when in the described step 6 the reacted product of hydrothermal crystallizing being dried, temperature is 105～130 ℃ of scopes.

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