CN105819496B - A kind of preparation method of hollow silver sulfide nanometer particles microballoon - Google Patents

Abstract

The invention discloses a kind of preparation method of hollow silver sulfide nanometer particles microballoon, using liquid-phase precipitation method, silver-colored source is provided with the hydrolysis of inorganic silver nitrate, sulphur source is hydrolyzed in acid condition with organic sodium thiosulfate to participate in and the hollow silver sulfide nanometer particles microballoon of silver ion reaction generation, any activating agent and stabilizer are added without in reaction, reaction at room temperature can obtain hollow silver sulfide nanometer particles microballoon.The inventive method is simple, and reaction is gentle, consumes energy small, synthesis step is few, simple to operate, to equipment without particular/special requirement, is adapted to large-scale production.It is demonstrated experimentally that obtained is hollow silver sulfide nanometer particles microballoon, a diameter of 1 3um of hollow silver sulfide nanometer particles microballoon.

Description

A kind of preparation method of hollow nanometer silver sulfide microsphere

technical field

The invention belongs to the technical field of preparation of inorganic functional materials, and specifically relates to a preparation method of hollow nanometer silver sulfide microspheres.

Background technique

In recent years, various nanomaterials with special structures and special shapes have attracted widespread attention, one of which is hollow microsphere nanostructured materials. Hollow microspheres are evolved from core/shell composite structure materials, and their properties can be controlled by adjusting the structure, size and composition of heterogeneous core/shell composite particles, so as to realize their optical, thermal, electrical, Extensive tailoring of magnetic and catalytic properties. They are usually composed of nanoparticles, whose size ranges from nanometers to micrometers, and are multi-scale and multi-level nanomaterials with hollow structures. Due to the characteristics of low density and high specific surface area of materials with this type of structure, and its hollow part can accommodate a large number of guest molecules or large-sized guests, it can produce some peculiar properties based on the microscopic "wrapping" effect, making hollow microspheres Materials have broad application prospects in many fields such as nano waveguides, high-efficiency sensing, optical transmission, catalytic separation, medical diagnosis, targeted therapy, thermal/acoustic insulation, etc.

Silver sulfide is an important transition metal chalcogenide compound, and it is also an important typical n-type semiconductor material, and silver sulfide is also a narrow band gap semiconductor material. Due to its unique physical and chemical properties, such as low density, high specific surface area, inner space and surface penetration, hollow nano-silver sulfide microspheres are widely used in photoelectric conversion, photocatalysis, hydrogen storage performance, electrode materials, biomedicine, etc. exhibit special properties. Therefore, nanostructured silver sulfide has broad application prospects in the fields of photocatalysis, photoelectric conversion, solar cells, solar radiation receivers, lithium-hydrogen batteries, photoelectric converters, and biomedicine. Furthermore, micro-nano silver sulfide has become a focus of attention and research by researchers in many disciplines such as materials, physics, chemistry, and optoelectronics. At present, new materials are obtained through simple and feasible synthesis methods and the corresponding experimental conditions can be changed to control the morphology of the composites, especially the synthesis of nano-sphere, square and worm-like nano-materials has attracted a large number of researchers on the physical and chemical properties of materials. interest of. Nowadays, many experimental methods have been applied to the preparation of nano-scale silver sulfide semiconductor materials, such as: chemical deposition method, hydrothermal method, electrodeposition method, solvothermal method, in-situ template control method, microwave-assisted method, etc.

The synthesis of nano-microspheres is even more complicated. The common preparation of nano-sized particles requires high temperature and high pressure conditions or the addition of surfactants (CTAB).

Contents of the invention

In view of the above deficiencies in the prior art, the purpose of the present invention is to provide a method for preparing hollow nano-silver sulfide microspheres. The method has simple equipment, low energy consumption, few synthesis steps, and simple operation. Reaction, suitable for large-scale production, and the performance of preparing silver sulfide is excellent and the purity is high.

The technical scheme that the present invention realizes that the object of its invention adopts is: a kind of preparation method of hollow nano-silver sulfide microspheres, and its concrete practice is:

a. Prepare mixed solution

Prepare a silver nitrate aqueous solution of a certain concentration and an aqueous sodium thiosulfate solution of the same concentration, then mix the silver nitrate solution and the sodium thiosulfate solution in a ratio of 1:3 to obtain a mixed solution in equimolar proportions, and leave it to stand for use;

b. Add mineral acid

Place the mixed solution in step a for a period of time, then take its supernatant to obtain a clear mixed solution, then drop a small amount of hydrochloric acid solution into the supernatant, stir evenly, and place it statically for 6 hours. During the standing process, there are gray precipitates in the solution matter generation;

c. Washing

When the precipitation in step b is stable, filter and wash the precipitate, first wash it with deionized water for several times and then wash it with absolute ethanol to obtain pure gray precipitate silver sulfide;

d. Sample drying

Place the gray silver sulfide obtained in step c into a vacuum drying oven, and dry it at 60°C for 5 hours to obtain the target product with a microsphere diameter of 1-3um.

The general mechanism of preparing hollow nano silver sulfide microspheres by the method of the present invention: hollow nano silver sulfide is synthesized by interfacial reaction, after silver nitrate solution and sodium thiosulfate solution are mixed, the mixed solution is alkaline, and sodium thiosulfate is hydrolyzed into Hydrogen sulfide is further hydrolyzed to S ₂ O ₃ ^2- , S ₂ O ₃ ^2- reacts with Ag ⁺ to form Ag ₂ (S ₂ O ₃ ) complex and does not produce silver sulfide precipitation. When adding a little inorganic acid to the mixed solution After the solution is acidic, the S ^2- produced by the hydrolysis of Ag ₂ (S ₂ O ₃ ) complex molecules reacts with Ag ⁺ ions and further generates silver sulfide molecules. These silver sulfide molecules aggregate to form nanoparticles, and the particles are connected to form surfaces and appear The agglomeration phenomenon is that the silver sulfide surface is rolled into hollow nano silver sulfide microspheres.

Compared with the prior art, the beneficial effects of the present invention are: the present invention adopts the liquid phase precipitation method, provides the silver source with the hydrolysis of inorganic silver nitrate, and uses organic sodium thiosulfate to hydrolyze into the sulfur source under acidic conditions to participate in the reaction with silver ions Generate hollow nano-silver sulfide microspheres. This reaction does not add any active agent and stabilizer, and the hollow nano-silver sulfide microspheres can be obtained by reacting at room temperature. The preparation method is simple, the reaction is mild, the energy consumption is small, the synthesis steps are few, and the operation Simple, no special requirements for equipment, suitable for mass production. Experiments prove that the prepared hollow nanometer silver sulfide microspheres have diameters ranging from 1 to 3 um.

Nanosulfides of various shapes that can be prepared by the method of the present invention, such as: synthesis of _CuS nanosheets and nanospheres, Ag2S nanospheres and worm-like nanoparticles, CdS nanospheres and SnS nanoparticles and other single inorganic sulfide. After the synthesis is completed, the obtained sulfide has definite structure, good purity, controllability and stable performance. These micro-nano-structured sulfides and composites have a wide range of uses and can be used as electrode materials for high-capacity Li/H batteries.

The adding amount and stirring speed of the mineral acid of above-mentioned b step.

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Fig. 1 is the XRD diffraction pattern of the hollow nano-silver sulfide microsphere prepared by the present invention.

Fig. 2 is a scanning electron microscope (SEM) image of the hollow nano-silver sulfide microspheres prepared in Example 1 of the present invention.

Fig. 3 is a scanning electron microscope (SEM) image of hollow nano-silver sulfide microspheres prepared in Example 2 of the present invention.

Fig. 4 is a scanning electron microscope (SEM) image of hollow nano-silver sulfide microspheres prepared in Example 3 of the present invention.

Fig. 5 is a scanning electron microscope (SEM) image of hollow nano-silver sulfide microspheres prepared in Example 4 of the present invention.

detailed description

Embodiment one

A kind of embodiment of the present invention is: a kind of preparation method of hollow nano-silver sulfide microspheres, and its concrete practice is:

a. Prepare mixed solution

Prepare 50ml of silver nitrate aqueous solution with a concentration of 0.01M in a beaker container; then prepare 150ml of an aqueous sodium thiosulfate solution with a concentration of 0.01M in a beaker container; then mix the silver nitrate solution and sodium thiosulfate solution in a ratio of 1:3 Corresponding to equimolar mixing to obtain a mixed solution and to stand for a period of time;

b. Add mineral acid

Put the mixed solution in step a for a period of time, then transfer the supernatant into another beaker to obtain a clear mixed solution, then drop a little 0.5M HCl solution 3ml into the beaker and stir it evenly, and let it stand still for 6h , gray precipitates were formed in the solution during the standing process;

c. Washing

When the amount of sediment generated in the beaker is basically the same, pour off the supernatant and wash the gray precipitate. First, wash it several times with deionized water and then wash it three times with absolute ethanol to obtain pure gray precipitate silver sulfide. up;

d. Sample drying

Put the beaker filled with gray silver sulfide into a vacuum drying oven, and dry it at 60°C for 5 hours to obtain a dry gray silver sulfide sample.

From the XRD pattern in Figure 1, it can be seen that the XRD ray diffraction peaks of the worm-like nano-silver sulfide prepared by this method are consistent with those on the PDF (00-014-0072) standard card. By comparison, it can be concluded that the worm-like nano-silver sulfide crystal type Belonging to the monoclinic crystal system, it is also silver sulfide of the pyridoxite type; there are no miscellaneous peaks in the diffraction peaks, indicating that the purity of the silver sulfide is relatively high, and there are no other impurities.

Fig. 2 is the scanning electron micrograph of the hollow nano-silver sulfide microspheres prepared after the solution of this example was allowed to stand for 6 hours, and the specific morphology of the silver sulfide microspheres can be clearly seen: hollow microspheres and spherical wall thickness are very thin, the hollow Silver sulfide microspheres are interconnected and curled into microspheres by nano-silver sulfide particles. The size of the particles is about 20nm, and the diameter of the formed hollow silver sulfide microspheres ranges from 0.8-2.5um.

Embodiment two

A kind of embodiment of the present invention is: a kind of preparation method of hollow nano-silver sulfide microspheres, and its concrete practice is:

a. Prepare mixed solution

Prepare 50ml of silver nitrate aqueous solution with a concentration of 0.02M in the beaker container; then prepare 150ml of sodium thiosulfate aqueous solution with a concentration of 0.02M in the beaker container; then mix the silver nitrate solution and sodium thiosulfate solution according to the ratio of 1:3 Corresponding to equimolar mixing to obtain a mixed solution and to stand for a period of time;

b. Add mineral acid

Put the mixed solution in step a for a period of time, then transfer the supernatant into another beaker to obtain a clear mixed solution, then drop a little 0.5M HCl solution 3ml into the beaker and stir it evenly, and let it stand still for 6h , gray precipitates were formed in the solution during the standing process;

c. Washing

When the amount of sediment generated in the beaker is basically the same, pour off the supernatant and wash the gray precipitate. First, wash it several times with deionized water and then wash it three times with absolute ethanol to obtain pure gray precipitate silver sulfide. up;

d. Sample drying

Put the beaker filled with gray silver sulfide into a vacuum drying oven, and dry it at 60°C for 5 hours to obtain a dry gray silver sulfide sample.

Fig. 3 is the scanning electron micrograph of the hollow nano-silver sulfide microsphere prepared after the solution of this example was allowed to stand for 6 hours, and the specific morphology of the silver sulfide can be clearly seen: the hollow microsphere and the spherical wall thickness are very thin, the hollow silver sulfide The microspheres are formed by interconnecting nano-silver sulfide particles and curled into microspheres. The size of the particles is about 20nm, and the diameter of the formed hollow silver sulfide microspheres ranges from 1.0-2.8um.

Embodiment three

A kind of embodiment of the present invention is: a kind of preparation method of hollow nano-silver sulfide microspheres, and its concrete practice is:

a. Prepare mixed solution

Prepare 50ml of silver nitrate aqueous solution with a concentration of 0.03M in the beaker container; then prepare 150ml of sodium thiosulfate aqueous solution with a concentration of 0.03M in the beaker container; then mix the silver nitrate solution and sodium thiosulfate solution according to the ratio of 1:3 Corresponding to equimolar mixing to obtain a mixed solution and to stand for a period of time;

b. Add mineral acid

Put the mixed solution in step a for a period of time, then transfer the supernatant into another beaker to obtain a clear mixed solution, then drop a little 0.5M HCl solution 5ml into the beaker and stir it evenly, and let it stand still for 6h , gray precipitates were formed in the solution during the standing process;

c. Washing

When the amount of sediment generated in the beaker is basically the same, pour off the supernatant and wash the gray precipitate. First, wash it several times with deionized water and then wash it three times with absolute ethanol to obtain pure gray precipitate silver sulfide. up;

d. Sample drying

Put the beaker filled with gray silver sulfide into a vacuum drying oven, and dry it at 60°C for 5 hours to obtain a dry gray silver sulfide sample.

Fig. 4 is the scanning electron micrograph of the hollow nano-silver sulfide microspheres prepared after the solution of this example was allowed to stand for 6 hours, and the specific morphology of the silver sulfide microspheres can be clearly seen: hollow microspheres and a spherical wall thickness of about 100nm, the Hollow silver sulfide microspheres are interconnected and curled into microspheres by nano-silver sulfide particles. The size of the particles is about 100nm, and the diameter of the formed hollow silver sulfide microspheres ranges from 0.5-2.0um.

Embodiment Four

A kind of embodiment of the present invention is: a kind of preparation method of hollow nano-silver sulfide microspheres, and its concrete practice is:

a. Prepare mixed solution

Prepare 50ml of silver nitrate aqueous solution with a concentration of 0.04M in the beaker container; then prepare 150ml of sodium thiosulfate aqueous solution with a concentration of 0.04M in the beaker container; then mix the silver nitrate solution and sodium thiosulfate solution according to the ratio of 1:3 Corresponding to equimolar mixing to obtain a mixed solution and to stand for a period of time;

b. Add mineral acid

Put the mixed solution in step a for a period of time, then transfer the supernatant into another beaker to obtain a clear mixed solution, then drop a little 0.5M HCl solution 5ml into the beaker and stir it evenly, and let it stand still for 6h , gray precipitates were formed in the solution during the standing process;

c. Washing

When the amount of sediment generated in the beaker is basically the same, pour off the supernatant and wash the gray precipitate. First, wash it several times with deionized water and then wash it three times with absolute ethanol to obtain pure gray precipitate silver sulfide. up;

d. Sample drying

Put the beaker filled with gray silver sulfide into a vacuum drying oven, and dry it at 60°C for 5 hours to obtain a dry gray silver sulfide sample.

Fig. 5 is the scanning electron micrograph of the hollow nano-silver sulfide microspheres prepared after the solution of this example was allowed to stand for 6 hours, and the specific morphology of the silver sulfide microspheres can be clearly seen: hollow microspheres and a spherical wall thickness of about 100nm, the Hollow silver sulfide microspheres are interconnected and curled into microspheres by nano-silver sulfide particles. The size of the particles is about 100nm, and the diameter of the formed hollow silver sulfide microspheres ranges from 0.5-2.0um.

Claims (4)

1. a kind of preparation method of hollow silver sulfide nanometer particles microballoon, its specific practice is：

A, preparation mixed solution

Configure the sodium thiosulfate solution of certain density silver nitrate aqueous solution and same concentration, then silver nitrate solution with Hypo solution is according to 1:3 ratio correspondence equimolar is mixed to get mixed solution, set aside for use；

B, addition inorganic acid

The a mixed solutions walked are placed its supernatant is taken after a period of time, the mixed solution clarified, then up in clear liquid Instill a small amount of hydrochloric acid solution to stir, static placement 6h has gray precipitate things generation in solution during standing；

C, washing

When b step is precipitated it is stable when, filtering precipitate washing is first washed with deionized for several times again after absolute ethyl alcohol is washed, Obtain pure gray precipitate things silver sulfide；

D, samples dried

Grey silver sulfide obtained by step c is inserted in vacuum drying chamber, drying 5h at 60 DEG C dries, and microsphere diameter is made in 1- 3um target product.

2. a kind of preparation method of hollow silver sulfide nanometer particles microballoon as claimed in claim 1, it is characterised in that：Described a steps Silver nitrate aqueous solution and the control of the sodium thiosulfate solution of same concentration are in 0.01-0.05M.

3. a kind of preparation method of hollow silver sulfide nanometer particles microballoon as claimed in claim 1, it is characterised in that：Described b steps Concentration of hydrochloric acid solution used is 0.5M.

4. a kind of preparation method of hollow silver sulfide nanometer particles microballoon as claimed in claim 1, it is characterised in that：Described c steps Centrifuge be low-speed centrifugal, to obtain micron ball object.