CN103934007A - Oxidization synthesis method for network structure of surface plasma visible light catalyst Ag/AgCl - Google Patents

Abstract

The invention relates to a method for oxidizing and synthesizing a network structure of surface plasmon visible light catalyst Ag/AgCl, which comprises the following two steps: 1. Synthesizing nanometer silver wires. Prepare silver salt and surfactant solution, add them dropwise into a three-necked flask filled with a small amount of organic solvent heated to a certain temperature, react for a period of time, and silver wires are formed. 2. Oxidation and ion exchange form Ag/AgCl network structure. Weigh the chlorate and make a solution. The solution was slowly added dropwise to the above system, reacted for a while, cooled, the sample was centrifuged, washed, dried, and the product was collected. The invention has simple process, common preparation conditions, stable product appearance, high purity, simple product treatment, and is suitable for medium-scale industrial production.

Description

Oxidation Synthesis Method of Network Structure of Surface Plasmon Visible Light Catalyst Ag/AgCl

technical field

The invention belongs to the technical field of inorganic nanometer materials, and in particular relates to an oxidation synthesis method of a network structure of a surface plasmon visible light catalyst Ag/AgCl.

Background technique

Nano science and technology is a new technology that is developing rapidly in the late 1980s. The so-called nanotechnology refers to the science and technology of manufacturing materials or micro-devices with units composed of several molecules or atoms—nanoparticles. Nanoparticles refer to fine particles of metals or semiconductors with a size ranging from 1 to 100 nm. The special structural level of nanoparticles endows it with many special properties and functions. Nanoparticles have a large specific surface area, and the number of surface atoms, surface energy and surface tension increase sharply with the decrease of particle size. Surface effects, small size effects , quantum size effect, macroscopic quantum tunneling effect and dielectric confinement effect lead to the thermal, magnetic, optical, sensitive characteristics and surface stability of nanoparticles are different from conventional particles, which makes it have a wide range of application prospects.

Silver halide is widely used in the manufacture of photo film, offset and gummed paper. Silver chloride also has a very important application in electrochemistry. The silver-silver chloride reference electrode is not easy to polarize, so it can provide more accurate data. Silver halide The photosensitivity and instability of silver halide limit its application in photocatalysis. If silver halide can be stabilized under light irradiation, it can be used in photocatalysis. Nanoscale metallic silver can be used in photocatalysis in the near ultraviolet region. With strong absorption, the absorption spectrum can be red-shifted by adjusting the size, shape and environment of the nanoparticles. In theory, silver nanoparticles can be used to enhance the absorption of sunlight by photocatalytic materials. In this experiment, silver and silver chloride are effectively compounded to form an Ag/AgCl network structure. First, due to the close contact between metallic silver and silver chloride, the electrons generated in the system can be more easily transferred to the metallic silver particles. First, it effectively promotes the separation of electrons and holes, thereby improving the quantum efficiency and ensuring the stability of the system; secondly, this novel network structure has a larger specific surface area, which can provide more photocatalytic active sites , improve the catalytic efficiency; again, the network structure of Ag/AgCl effectively expands the response of the system to visible light, making it have strong absorption in the entire visible light region, which greatly improves the utilization rate of sunlight. This method broadens the way to enhance the visible light absorption of photocatalytic materials through the metal surface plasmon resonance effect, thereby improving the performance of photocatalytic materials.

Contents of the invention

The object of the present invention is to provide a method for oxidizing and synthesizing the network structure of surface plasmon visible light catalyst Ag/AgCl.

In order to achieve the above object, the technical scheme of the present invention is as follows:

A kind of oxidative synthesis method of the network structure of surface plasmon visible light catalyst Ag/AgCl, concrete steps are as follows:

(1) Synthesis of silver nanowires

Weigh the silver salt and surfactant, and dissolve them in the solvent respectively to obtain the silver salt solution and the surfactant solution; take a small amount of solvent in a three-necked flask, stir magnetically and heat to 160~180°C until the temperature of the solvent is stable Finally, the silver salt solution and the surfactant solution are added dropwise into the three-necked flask at the same time, and after 70-80 minutes of reaction, nano-silver wires are generated; wherein: the molar ratio of the silver salt to the surfactant is 1:1 ;

(2) Oxidation and ion exchange to form Ag/AgCl network structure

Weigh the chlorate, dissolve it in a solvent to obtain a chlorate solution, slowly add the solution to the system obtained in step (1), react for 0-60 minutes, cool, centrifuge the sample, wash, and dry to obtain the obtained Required product: Among them: the molar ratio of silver salt and chlorate is 1:1.

In the present invention, the solvents described in step (1) and step (2) are all ethylene glycol, and the purity grade is analytically pure.

In the present invention, the silver salt is silver nitrate, and its concentration is 0.12mol/L.

In the present invention, the surfactant is polyvinylpyrrolidone with an average molecular mass of 1,300,000.

In the present invention, the chlorate is copper chloride, and its concentration is 0.12mol/L.

In the present invention, an oil bath is used for heating in step (1), and a condensation reflux device is provided in the whole heating process.

In the present invention, the washing in step (2) is washing the product with ethanol and deionized water respectively.

In the present invention, the drying in step (2) is drying in a vacuum oven at 60°C for 10 hours.

Due to the adoption of the above scheme, the present invention has the following beneficial effects:

1. The present invention realizes the first synthesis of a composite material with Ag/AgCl network structure by using common copper salt and chlorate as precursors through heating and reflux.

2. The method of the present invention has high controllability to the morphology of the product.

3. The present invention adopts simple inorganic salts as reactants and has strong versatility.

4. The product prepared by the present invention has good photocatalytic degradation performance on organic pollutants, can be used as a high-performance photocatalyst, and has relatively broad development prospects and application space.

5. The process of the present invention is simple, the preparation conditions are common, the product is stable in appearance, high in purity, and the product is convenient and simple to handle, which is suitable for medium-scale industrial production.

6. The method of the present invention has the characteristics of mild conditions, uniform heating, energy saving and high efficiency, and easy control.

Description of drawings

Fig. 1 is the SEM picture of the intermediate product obtained under the multiple of 200nm in embodiment 1.

Fig. 2 is the SEM photo of the product obtained at the multiple of 600nm in Example 1.

FIG. 3 is a TEM photo of the product obtained in Example 1 at a multiple of 200 nm.

Fig. 4 is the XRD spectrum of the product obtained in Example 1.

Figure 5 is the EDS spectrum of the product obtained in Example 1.

FIG. 6 is a SEM photo of the product obtained in Example 2 at a multiple of 200 nm.

Figure 7 is a SEM photo of the product obtained in Example 3 at a multiple of 200 nm.

Detailed ways

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

Example 1

Step 1: Weigh 0.204g AgNO ₃ , 0.1332g polyvinylpyrrolidone (PVP), 0.204g CuCl ₂ 2H ₂ O into three 20ml reaction flasks labeled A, B, and C respectively, and add 10ml of ethylene glycol was sonicated until dissolved into a clear solution.

Step 2: Measure 10ml of ethylene glycol into a 50ml three-necked flask, add magnets, fix it on the iron stand, place it in the oil bath, set up the reflux condensation device, and turn on the switch of the reflux water and the oil bath , set the temperature to 160°C, and turn on the magnetic stirring.

Step 3: Wait for the oil bath to reach the set temperature and stabilize, and at the same time add AgNO ₃ solution and PVP solution drop by drop for ten minutes.

Step 4: react for 80 minutes, the solution turns milky white, add CuCl ₂ solution dropwise, and the dropping time lasts for 10 minutes.

Step 5: React for ten minutes, turn off the oil bath and condensed water, remove the oil bath from the liquid surface, cool to room temperature, wash with absolute ethanol and deionized water several times, and dry in a vacuum oven.

Fig. 1 is the SEM photograph of the intermediate product silver line product obtained under the multiple of 200nm in embodiment 1; Fig. 2 is the SEM photograph of the product obtained under the multiple of 200nm in embodiment 1; Fig. 3 is the product obtained in embodiment 1 TEM picture; Figure 4 is the XRD pattern of the product obtained in Example 1, indicating that both AgCl and Ag exist in the complex. Figure 5 is the EDS spectrum of the product obtained in Example 1. The number of Ag atoms is more than that of Cl, which further proves that the product is an Ag/AgCl complex.

Example 2

Step 1: Weigh 0.204g AgNO3, 0.1332g polyvinylpyrrolidone (PVP), 0.102g CuCl ₂ 2H ₂ O into three 20ml reaction bottles labeled A, B, and C respectively, add 10ml Ethylene glycol was sonicated until dissolved into a clear solution.

Step 2: Measure 10ml of ethylene glycol into a 50ml three-necked flask, add magnets, fix it on the iron stand, place it in the oil bath, set up the reflux condensation device, and turn on the switch of the reflux water and the oil bath , set the temperature to 160°C, and turn on the magnetic stirring.

Step 3: Wait for the oil bath to reach the set temperature and stabilize, and at the same time add AgNO3 solution and PVP solution drop by drop for ten minutes.

Step 4: react for 80 minutes, the solution turns milky white, add CuCl ₂ solution dropwise, and the dropping time lasts for 10 minutes.

Step 5: React for 40 minutes, close the oil bath and condensed water, remove the oil bath from the liquid surface, cool to room temperature, wash with absolute ethanol and deionized water several times, and dry in a vacuum oven.

FIG. 5 is a SEM photo of the product obtained in Example 2 at a multiple of 200 nm. It can be seen from the picture that the Ag/AgCl network structure can still be formed under this condition, but the network is thicker and the relative specific surface area is smaller.

Example 3

Step 1: Weigh 0.204g AgNO ₃ , 0.1332g polyvinylpyrrolidone (PVP), 0.204g CuCl ₂ 2H ₂ O into three 20ml reaction flasks labeled A, B, and C respectively, and add 10ml of ethylene glycol was sonicated until dissolved into a clear solution.

Step 2: Measure 10ml of ethylene glycol into a 50ml three-necked flask, add magnets, fix it on the iron stand, place it in the oil bath, set up the reflux condensation device, and turn on the switch of the reflux water and the oil bath , set the temperature to 180°C, and turn on the magnetic stirring.

Step 3: Wait for the oil bath to reach the set temperature and stabilize, and at the same time add AgNO3 solution and PVP solution drop by drop for ten minutes.

Step 4: react for 80 minutes, the solution turns milky white, add CuCl2 solution drop by drop, and the dropwise addition time lasts 10 minutes.

Step 5: React for 40 minutes, close the oil bath and condensed water, remove the oil bath from the liquid surface, cool to room temperature, wash with absolute ethanol and deionized water several times, and dry in a vacuum oven.

FIG. 6 is a SEM photo of the product obtained in Example 2 at a multiple of 200 nm. It can be seen from the picture that the Ag/AgCl network structure can still be formed under this condition, and the network spacing is relatively large and relatively loose.

The above description of the embodiments is for those of ordinary skill in the art to understand and apply the present invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments, and apply the general principles described here to other embodiments without creative effort. Therefore, the present invention is not limited to the embodiments herein, and modifications made without departing from the scope of the present invention are within the protection scope of the present invention.

Claims (8)

1. an oxidation synthesis method for the network structure of surface plasma visible light catalyst Ag/AgCl, is characterized in that concrete steps are as follows:

(1) nano-silver thread is synthetic

Take silver salt and surfactant, it is dissolved in respectively in solvent, obtain silver salt solution and surfactant solution; Take a morsel solvent in three-neck flask, and magnetic agitation is also heated to 160 ~ 180 DEG C, after solvent temperature is stable, silver salt solution and surfactant solution is dropwise joined in described three-neck flask simultaneously, reacts after 70-80 minute, generates nano-silver thread; Wherein: the mol ratio of silver salt and surfactant is 1:1;

(2) oxidation and ion-exchange form Ag/AgCl network structure

Take chlorate, be dissolved in solvent, obtain solution of chlorate, solution is slowly joined in step (1) gained system, reaction 0-60 minute, cooling, sample is carried out centrifugal, washing, dry, obtain required product: wherein: the mol ratio of silver salt and chlorate is 1:1.

2. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, it is characterized in that: described in step (1) and step (2), solvent is ethylene glycol, purity level is pure for analyzing.

3. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: described silver salt is silver nitrate, and its concentration is 0.12mol/L.

4. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: described surfactant is polyvinylpyrrolidone, and its average molecular mass is 1300000.

5. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: described chlorate is copper chloride, and its concentration is 0.12mol/L.

6. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: step adds thermal recovery oil bath pan described in (1), and whole heating process has condensation reflux unit.

7. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: the described washing of step (2) is by ethanol and deionized water washed product respectively.

8. the oxidation synthesis method of the network structure of a kind of surface plasma visible light catalyst Ag/AgCl according to claim 1, is characterized in that: dry described in step (2) is dry 10h in 60 DEG C of vacuum drying chambers.