CN106694903B - A kind of CuCl/Cu2The preparation method and products obtained therefrom of O/Cu porous nano-sheets - Google Patents

Abstract

The invention discloses a preparation method of CuCl/Cu ₂ O/Cu porous nanosheet and the obtained product. The method is as follows: adding copper chloride, NaHCO ₃ , and EDTA‑2Na into a mixed solvent of glycerol and ethanol, and stirring to obtain Transparent solution, the transparent solution is subjected to solvothermal reaction, and the obtained product is centrifuged and washed to obtain the product. The present invention controls the grain nucleation and growth process of CuCl, Cu ₂ O and Cu by adjusting process parameters such as reaction system and solvothermal reaction conditions, and under the synergistic effect of surfactants, reducing agents, etc., to obtain uniform morphology, CuCl/Cu ₂ O/Cu porous nanosheets with tunable thickness and pore size. The raw materials used in this method are low in price, wide in sources, and highly controllable in reaction. Products with uniform microscopic morphology, narrow size distribution range, and high yield can be obtained by only one-step solvothermal reaction. Lithium battery and other fields have high application value.

Description

A kind of preparation method of CuCl/Cu2O/Cu porous nano sheet and the product obtained therefrom

technical field

The invention relates to a method for preparing a CuCl-based three-phase composite nanostructure, in particular to a method for preparing a CuCl/Cu ₂ O/Cu porous nanosheet with adjustable thickness and pore diameter and the resulting product, belonging to the technical field of nanomaterial preparation.

Background technique

With the increasingly serious crisis of energy and ecological environment, the use of non-toxic raw materials, the exploration of green chemical synthesis processes that can reduce environmental pollution, and the development of "environmentally friendly" nano-functional materials that meet the needs of the country's energy-saving emission reduction and circular economy are the current light. Research hotspots in the fields of catalysis, catalysis, gas sensing, and lithium batteries. Research and development of new multi-phase composite nanostructure system is considered to be a feasible and effective way.

Copper-based compounds have the characteristics of cheap and easy to obtain, high reactivity, good selectivity, and recyclability, and have great industrial application prospects in the fields of catalysis, energy, and sensing. Among them, CuCl is a type I-VII direct bandgap wide-bandgap semiconductor with room temperature sphalerite structure, which is used in electro-optic modems, LEDs, adsorbents, air purifiers, optical filters, organic synthesis catalysts, lithium batteries, etc. widely. There are many synthesis methods of CuCl nanocrystals, thin films and powders, for example, the reduction reaction method of Cu ²⁺ /hydrochloric acid solution, the high temperature ion implantation method, the thermal decomposition method of organic copper compounds, the vacuum reaction method of Cu single crystal/chlorine gas, etc. , most of these synthesis processes require complex equipment, high-temperature reactions, toxic raw materials and solvents, and are accompanied by the generation of polluting by-products. In addition, the use of CuCl materials alone often has problems such as poor stability, easy deactivation, and severe corrosion, which greatly limits Applications of CuCl micro-nano materials. Studies have found that the service life and activity of CuCl can be effectively improved and its corrosion to equipment can be reduced by adding additives or ligands, introducing second phase substances, and adjusting microscopic morphology. For example, "RCYang, XJ Lu, X. Huang, ZM Chen, X. Zhang, MD Xu, QW Song, and LT Zhu, Applied Catalysis B: Environmental, 2015, 170-171, 225-232" uses CuCO ₃ -Cu (OH) ₂ , glucose as raw material, deionized water as solvent, obtained Cu ₂ O/CuCl cubic structure by solvothermal method, and found that it has good photocatalytic performance; "S. Liu, HY Hou, XX Liu, W. Hu, CX Yan, JXDuan, and RJ Meng, Ceramics International, 2016, 42, 8310-8315 "Prepared CuCl/Cu hierarchical scale structure by in situ growth method, and found that it has excellent lithium battery performance.

At present, a variety of CuCl-based two-phase composite nanostructures have been explored at home and abroad, but the research on CuCl/Cu ₂ O/Cu three-phase composite sheet structure has not been reported yet. Solvothermal reaction has the advantages of simple operation and good repeatability. If one-step solvothermal reaction can be used to effectively control the phase composition and microscopic morphology of CuCl-based composite nanomaterials, it will not only significantly improve the physical and chemical properties of CuCl materials, but also solve the problem of existing problems. The common problems of small output and poor controllability in the synthesis process of CuCl nanomaterials in the first stage will help to realize the further application of CuCl/Cu ₂ O/Cu composite nanostructures in the fields of photocatalysis, catalysis, gas sensing, lithium batteries, etc. .

Contents of the invention

Aiming at the deficiencies in the existing methods, the present invention provides a method for preparing CuCl/Cu ₂ O/Cu nanosheets. The method uses a one-step solvothermal reaction to prepare CuCl/Cu ₂ O/Cu three-phase composite nanosheet materials. The synthesis process is easy to control, has strong operability, good product morphology repeatability, strong controllability, and is conducive to large-scale production.

The present invention also provides CuCl/Cu ₂ O/Cu nano-sheets prepared according to the above method, the nano-sheets are composed of CuCl/Cu ₂ O/Cu three-phase composite, and there is no relevant report so far.

The present invention is completed under the support of the National Natural Science Foundation of China Youth Science Fund Project (project approval number: 51402123), and its specific technical scheme is as follows:

A method for preparing CuCl/Cu ₂ O/Cu porous nanosheets is characterized by comprising the following steps:

(1) Add copper chloride, NaHCO ₃ , and EDTA-2Na into a mixed solvent of glycerol and ethanol, and stir to obtain a transparent solution;

(2) heating the transparent solution in step (1) to perform solvothermal reaction;

(3) After the reaction, the product is centrifuged and washed to obtain CuCl/Cu ₂ O/Cu porous nanosheets.

In the above method, in step (1), the molar ratio of copper chloride, NaHCO ₃ , and EDTA-2Na is 1:0.6-1.4:0.5-0.9.

In the above method, in step (1), the volume ratio of glycerol and ethanol is 1:0.5-1.5.

In the above method, in step (1), the concentration of copper chloride in the mixed solvent of glycerol and ethanol is 0.12-0.36 mol/L.

In the above method, in step (2), the solvothermal reaction temperature is 190-220° C., and the reaction time is generally 1-24 h.

In the above method, in step (2), the solvothermal reaction is carried out under airtight conditions.

The present invention prepares CuCl/Cu ₂ O/Cu three-phase composite nanomaterials only through one-step solvothermal reaction. The reaction system is novel and the reaction process is easy to control. By controlling the composition and content of the reaction system, solvothermal reaction conditions and other process parameters, CuCl/Cu ₂ O/Cu porous nanosheets with uniform appearance, adjustable thickness and pore diameter can be obtained. The present invention is innovative in reaction system, product crystal phase, product morphology, reaction mechanism, etc., and is substantially different from domestic and foreign literature reports. In the present invention, glycerol is a solvent, a reducing agent and an organic ligand, _NaHCO is a weak base source and a surfactant, and ETDA-2Na is a complexing agent and a surfactant. , under the action of surfactants, the glycerol copper flake structure is first formed through solvothermal reaction, and then the glycerol copper flake structure is used as a soft template, which can effectively promote glycerol copper in the reducing solvent environment provided by glycerol and ethanol. The transformation of Cu ²⁺ in the sheet structure to Cu ⁺ , a part of Cu ⁺ reacts with Cl ^- in the solution to form CuCl, another part of Cu ⁺ reacts with OH ^- in the solution to form Cu ₂ O, and a part of Cu ⁺ further It is reduced to form Cu simple substance. During the process of this series of redox reactions, the morphology of the product maintains the nanosheet structure of the glycerol copper template, and the overall appearance is porous. Finally, a multi-component composite nanomaterial containing three crystal phase structures of CuCl, Cu ₂ O and Cu is obtained.

The CuCl/Cu ₂ O/Cu porous nano sheet obtained according to the method of the present invention has special composition and morphology, and is also within the protection scope of the present invention.

The CuCl/Cu ₂ O/Cu porous nano sheet prepared by the invention has a size of 0.06-2.5 μm, a thickness of 5-100 nm, and a pore diameter of 1-20 nm. Wherein, the pore size can be measured by a transmission electron microscope or a specific surface area meter.

The present invention controls CuCl, Cu, etc. under the synergy of surfactants, reducing agents, _{etc. 2} O and Cu grain nucleation and growth process, to obtain CuCl/Cu ₂ O/Cu porous nanosheets with uniform morphology, adjustable thickness and pore size, the choice of reaction system is very important for CuCl/Cu ₂ O/Cu porous nanosheets The formation process and shape control play an important role. The reaction system and synthesis process of the invention are practical, and the technical route and reaction mechanism are highly innovative.

The present invention adopts a one-step solvothermal reaction process to prepare CuCl/Cu ₂ O/Cu three-phase composite nanomaterials. The raw materials used are all commonly used reagents, with low price, wide sources, strong reaction controllability, easy operation, and excellent microscopic appearance of the product. Uniformity, good repeatability, narrow size distribution range, high yield, and high application value in photocatalysis, catalysis, gas sensing, lithium batteries and other fields.

Description of drawings

FIG. 1 is an X-ray diffraction (XRD) pattern of CuCl/Cu ₂ O/Cu porous nanosheets synthesized in Example 1 of the present invention.

FIG. 2 is a scanning electron microscope (SEM) picture of CuCl/Cu ₂ O/Cu porous nanosheets synthesized in Example 1 of the present invention.

Fig. 3 is a transmission electron microscope (TEM) image of CuCl/Cu ₂ O/Cu porous nanosheets synthesized in Example 1 of the present invention.

Detailed ways

The present invention is further elaborated below through the examples, and the following description is only for explaining the present invention, and its content is not limited.

Example 1

1.1 Add 0.852 g of copper chloride dihydrate (CuCl ₂ ∙ 2H ₂ O), 0.425 g of NaHCO ₃ , and 1.316 g of EDTA-2Na into a mixed solvent of 12.5 mL of glycerol and 12.5 mL of ethanol, and stir to obtain a transparent solution ;

1.2 Transfer the above solution to the reactor and react at 200 °C for 16 h;

1.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained.

The phase structure and microscopic morphology of the product are shown in Figure 1-3. Figure 1 is the XRD pattern of the product. It can be found that all the X-ray diffraction peaks are consistent with the JCPDS card (06-0344, 05-0667, 04-0836), corresponding to CuCl, Cu ₂ O and Cu crystal phases, proving that CuCl, Cu ₂ O and Cu exist in the obtained product at the same time, which is a three-phase composite structure of CuCl/Cu ₂ O/Cu; Figure 2 and 3 are the SEM and TEM photos of the product respectively, and it can be found that the product shown in the SEM and TEM pictures The microscopic morphology is consistent, and they are all porous nanosheet structures with good dispersion and uniform appearance. The size of the nanosheets is 0.18-0.25 μm, the thickness is 37-43 nm, and the pore diameter is 2.5-6.0 nm.

Example 2

2.1 Add 0.560 g of CuCl ₂ ∙ 2H ₂ O, 0.168 g of NaHCO ₃ , and 0.623 g of EDTA-2Na into a mixed solvent of 15.0 mL of glycerol and 10.0 mL of ethanol, and stir to obtain a transparent solution;

2.2 Transfer the above solution to the reactor and react at 190 °C for 2 h;

2.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained. The size of the nanosheets is 0.08-0.13 μm, the thickness is 7-11 nm, and the pore size is 1.1-2.3 nm.

Example 3

3.1 Add 1.868 g of CuCl ₂ ∙ 2H ₂ O, 1.273 g of NaHCO ₃ , and 3.625 g of EDTA-2Na into a mixed solvent of 10.4 mL of glycerol and 20.6 mL of ethanol, and stir to obtain a transparent solution;

3.2 Transfer the above solution to the reactor and react at 220 °C for 23 h;

3.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained. The size of the nanosheets is 1.8-2.2 μm, the thickness is 88-94 nm, and the pore size is 12.0-18.0 nm.

Example 4

4.1 Add 1.254 g of CuCl ₂ ∙ 2H ₂ O, 0.618 g of NaHCO ₃ , and 1.642 g of EDTA-2Na into a mixed solvent of 14.0 mL of glycerol and 12.0 mL of ethanol, and stir to obtain a transparent solution;

4.2 Transfer the above solution to the reactor and react at 200 °C for 10 h;

4.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained. The size of the nanosheets is 0.10-0.15 μm, the thickness is 22-28 nm, and the pore size is 1.9-5.1 nm.

Example 5

5.1 Add 1.248 g of CuCl ₂ ∙ 2H ₂ O, 0.738 g of NaHCO ₃ , and 2.179 g of EDTA-2Na into a mixed solvent of 18.0 mL of glycerol and 13.5 mL of ethanol, and stir to obtain a transparent solution;

5.2 Transfer the above solution to the reactor and react at 210 °C for 20 h;

5.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained. The size of the nanosheets is 1.4-1.8 μm, the thickness is 63-70 nm, and the pore size is 7.0-13.0 nm.

Example 6

6.1 Add 0.930 g of CuCl ₂ ∙ 2H ₂ O, 0.367 g of NaHCO ₃ , and 1.523 g of EDTA-2Na into a mixed solvent of 14.0 mL of glycerol and 16.0 mL of ethanol, and stir to obtain a transparent solution;

6.2 Transfer the above solution to the reactor and react at 220 °C for 4 h;

6.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu porous nanosheets are obtained. The size of the nanosheets is 0.9-1.5 μm, the thickness is 54-60 nm, and the pore size is 5.2-10.5 nm.

Comparative example 1

1.1 Add 1.254 g of CuCl ₂ ∙ 2H ₂ O and 0.618 g of NaHCO ₃ into a mixed solvent of 14.0 mL of glycerol and 12.0 mL of ethanol, and stir to obtain a transparent solution;

1.2 Same as embodiment 4;

1.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu blocky particles with irregular shape, obvious agglomeration and large size distribution range (0.15-0.85 μm) are obtained, and CuCl/Cu ₂ O/Cu porous particles cannot be obtained nanosheet structure. It shows that the introduction of EDTA-2Na directly affects the formation process and size of the product morphology.

Comparative example 2

2.1 Add 1.254 g of CuCl ₂ ∙ 2H ₂ O, 20 wt% ammonia water (0.0074 mol NH ₃ ·H ₂ O), and 1.642 g of EDTA-2Na into a mixed solvent of 13.0 mL of ethanol and 13.0 mL of ethylene glycol, Stir to obtain a transparent solution;

2.2 Same as embodiment 4;

2.3 After the product is centrifuged and washed, CuO/Cu ₂ O blocky particles with poor dispersion, irregular shape, and large size distribution range (0.45-3.65 μm) are obtained, and CuCl/Cu ₂ O/Cu porous nanosheets cannot be obtained structure. It shows that the composition of the transparent solution directly affects the crystal phase composition and microscopic morphology of the product.

Comparative example 3

3.1 Add 2.686 g of CuCl ₂ ∙ 2H ₂ O, 0.395 g of NaHCO ₃ , and 8.798 g of EDTA-2Na into a mixed solvent of 5.0 mL of glycerol and 21.0 mL of ethanol, and stir to obtain a transparent solution;

3.2 Same as embodiment 4;

3.3 After the product is centrifuged and washed, CuCl/Cu ₂ O/Cu blocky particles with irregular shape, obvious agglomeration and large size distribution range (0.35-2.55 μm) are obtained, and CuCl/Cu ₂ O/Cu porous particles cannot be obtained nanosheet structure. It shows that the concentration of the reaction system directly affects the formation process and size of the product morphology.

Comparative example 4

4.1 Add 1.777g of copper nitrate trihydrate (Cu(NO ₃ ) ₂ ∙3H ₂ O), 0.618 g of NaHCO ₃ , and 1.642 g of EDTA-2Na into a mixed solvent of 14.0 mL of glycerol and 12.0 mL of ethanol, and stir Obtain a transparent solution;

4.2 Same as embodiment 4;

4.3 After the product is centrifuged and washed, Cu ₂ O/Cu block particles with irregular shape, obvious agglomeration and large size distribution range (0.25-2.95 μm) are obtained. It shows that the type of reaction raw materials also has an important influence on the product morphology.

Claims (5)

1. A method for preparing CuCl/Cu ₂ O/Cu porous nanosheets, characterized in that it comprises the following steps: (1) Add copper chloride, NaHCO ₃ , and EDTA-2Na into a mixed solvent of glycerol and ethanol, and stir to obtain a transparent solution; (2) heating the transparent solution in step (1) to perform solvothermal reaction; (3) After the reaction, centrifuge and wash the product to obtain CuCl/Cu ₂ O/Cu porous nanosheets; The molar ratio of copper chloride, NaHCO ₃ , and EDTA-2Na is 1:0.6-1.4:0.5-0.9; The volume ratio of glycerol and ethanol is 1:0.5-1.5; The solvothermal reaction temperature is 190-220°C, and the reaction time is 1-24 h. 2. preparation method according to claim 1 is characterized in that: the concentration of cupric chloride in the mixed solvent of glycerol and ethanol is 0.12-0.36 mol/L. 3. The preparation method according to claim 1, characterized in that: the solvothermal reaction is carried out under airtight conditions. 4. The preparation method according to claim 1, 2 or 3, characterized in that: the size of the obtained CuCl/Cu ₂ O/Cu porous nanosheets is 0.06-2.5 μm, the thickness of the nanosheets is 5-100 nm, and the pore diameter is 1-20 nm. 5. CuCl/ _Cu2O /Cu porous nanosheets prepared according to the method for preparing CuCl/ _Cu2O /Cu porous nanosheets according to any one of claims 1-4.