A method for preparing symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material

Abstract

This invention relates to a method for preparing a symmetrical eight-arrowhead-shaped dendritic AgCl / Ag powder material. The method involves first reacting Cu-Ag-Ca-Mg amorphous ribbons with hydrochloric acid solution to obtain Cu-Ag nanoporous materials. Then, the Cu-Ag nanoporous materials are reacted with a hydrochloric acid-ethanol mixture under ultrasonic assistance. The Cu-Ag nanoporous materials dissolve sequentially in the hydrochloric acid-ethanol solution. After the ultrasonic treatment stops, AgCl nucleates and precipitates. Through irradiation, the surface of AgCl partially decomposes to obtain nano-Ag particles that adhere to the AgCl surface, thus obtaining the symmetrical eight-arrowhead-shaped dendritic AgCl / Ag powder material. This invention offers a simple process, and the resulting nano-AgCl / Ag structure exhibits symmetry, demonstrating superior performance in photocatalysis and sterilization.

Description

Technical Field

[0001] This invention relates to the field of catalysis technology, and in particular to a method for preparing symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material. Background Technology

[0002] AgCl powder, as an inorganic compound, is widely used in fields such as photography, photosensitive printing, environmental protection, and photocatalysis. Nano-Ag has wide applications in antibacterial, optical, catalytic, and biomedical fields. Combining AgCl and Ag to obtain AgCl / Ag powder materials will possess the various properties of both AgCl and Ag, greatly expanding their application range. However, currently, the preparation of AgCl / Ag powder materials typically uses natural hot springs, NaCl, CCl4, aluminum chloride, FeCl3, etc., as Cl- sources. - The source, AgNO3, CH3COOAg, AgNO3, etc. provide Ag+ sources, and the preparation methods and processes are complex.

[0003] Patent application number CN202010171337.4 discloses an AgCl / Ag composite material and its preparation method. The method uses water as the solvent of the reaction solution and requires a long ultrasonic reaction time to obtain an AgCl / Ag composite material with a "flower ball" shape. The individual "flower ball" structure is relatively compact, and the contact area is small during catalysis, which will affect the catalytic reaction rate. Summary of the Invention

[0004] Based on this, and to address the aforementioned problems, a method for preparing symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material is provided:

[0005] A method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material, characterized by comprising the following steps:

[0006] Amorphous initial alloy strips are provided, wherein the initial alloy has the composition of Ca. 40 Mg 20 Cu 20 Ag 20 (Atomic percentage), the amorphous initial alloy strips were reacted with an acid solution to obtain Cu-Ag nanoporous material whose main components are Cu and Ag;

[0007] Cu-Ag nanoporous material was reacted with an excess hydrochloric acid-ethanol solution under ultrasonic-assisted conditions. When the ultrasonic time exceeded 10 min, the Cu-Ag nanoporous material completely dissolved in the excess hydrochloric acid-ethanol solution, yielding a pale yellow, clear intermediate solution. The hydrochloric acid-ethanol solution was prepared by mixing 12 mol / L hydrochloric acid aqueous solution with ethanol, and the volume ratio of the 12 mol / L hydrochloric acid aqueous solution to ethanol was in the range of 0.9–1.1. The volume of the Cu-Ag nanoporous material was less than 1 / 200 of the volume of the hydrochloric acid-ethanol solution, ensuring a sufficient excess of the hydrochloric acid-ethanol solution.

[0008] Stop the ultrasound, and a white solid substance slowly precipitates from the pale yellow clear intermediate solution. Collect the white solid substance to obtain symmetrical eight-arrow-shaped dendritic AgCl powder material.

[0009] The surface portion of the symmetrical eight-arrow-shaped dendritic AgCl powder particles was photodecomposed to obtain nano-Ag particles, thus obtaining the symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material.

[0010] The eight arrowhead-shaped dendrite AgCl powder particles are composed of eight arrowhead-shaped dendrites symmetrically distributed in three-dimensional space, and the eight arrowhead-shaped dendrites are connected by a common nucleation point region.

[0011] Furthermore, the initial amorphous alloy strip is obtained in the following manner:

[0012] The alloy raw materials are prepared according to atomic percentage and melted to obtain an alloy melt. The alloy melt is then processed into 20-100μm amorphous strips using a copper roller spinning machine.

[0013] The linear speed of the roller surface of the copper roller spinning machine is 40m / s-45m / s.

[0014] Furthermore, during the reaction of the amorphous initial alloy strip with the acid solution, the acid solution includes at least one of hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid;

[0015] Furthermore, the total atomic percentage of Cu and Ag in the Cu-Ag nanoporous material exceeds 98%. Other elements besides Cu and Ag mainly include incompletely dissolved Mg and Ca.

[0016] Further, the ultrasound time exceeds 5 minutes and is less than 30 minutes. Preferably, the ultrasound time exceeds 5 minutes and is less than 20 minutes; more preferably, the ultrasound time exceeds 5 minutes and is less than 15 minutes.

[0017] Furthermore, the volume ratio of the 12 mol / L hydrochloric acid aqueous solution to the ethanol solution is 1.

[0018] Furthermore, the ultrasonic frequency is 40-80 kHz; preferably, the ultrasonic frequency is 40 kHz.

[0019] Furthermore, the volume of the Cu-Ag nanoporous material is less than 1 / 1000 of the volume of the hydrochloric acid ethanol solution.

[0020] Furthermore, the reason why the pale yellow clear intermediate solution appears pale yellow is that CuCl2 also appears pale yellow in ethanol solution.

[0021] Furthermore, the temperature of the hydrochloric acid ethanol solution is 20℃-100℃; preferably, the temperature of the hydrochloric acid ethanol solution is 60℃.

[0022] Furthermore, the symmetrical eight-arrow-shaped dendrite AgCl surface partially decomposes into Ag through at least one of sunlight, electron beam, and ultraviolet irradiation.

[0023] Preferably, the symmetrical eight-arrow-shaped dendrite AgCl surface is partially photodecomposed into Ag by ultraviolet irradiation.

[0024] Furthermore, the size of the symmetrical eight-arrow-shaped dendritic AgCl / Ag powder particles is 0.5μm-8μm, and the size of the nano Ag particles is 2nm-50nm.

[0025] Preferably, the size of the symmetrical eight-arrow-shaped dendritic AgCl particles in the symmetrical eight-arrow-shaped dendritic AgCl / Ag powder particles is 0.5μm-3μm, and the size of the nano Ag particles is 2nm-25nm.

[0026] The inventiveness of this application is mainly reflected in the following two aspects:

[0027] First, by introducing ethanol as a key solvent component in the hydrochloric acid-ethanol solution, the rapid dissolution of Cu-Ag nanoporous materials is significantly promoted. According to CN202010171337.4, an AgCl / Ag composite material and its preparation method are disclosed. This method uses water as the solvent in the hydrochloric acid solution and requires at least 30 minutes of reaction time to obtain a "flower-shaped" AgCl / Ag composite material. This application, by introducing ethanol as a key solvent component with at least half its volume content, reduces the reaction time to as low as 5 minutes, significantly lowering costs and reducing reaction time. The reason for the shortened reaction time is unknown, but it is possible that the presence of ethanol in the solvent, and its volume content being approximately half of the total solvent volume, can significantly promote the dissolution process of Cu-Ag nanoporous materials.

[0028] Secondly, by cleverly selecting the ratio of hydrochloric acid to ethanol solution, specifically choosing a volume ratio of 12 mol / L hydrochloric acid aqueous solution to ethanol in the range of 0.9–1.1, not only was the dissolution time of Cu-Ag nanoporous materials significantly shortened, but the morphology of the product was also fundamentally affected. According to CN202010171337.4, an AgCl / Ag composite material and its preparation method are disclosed. This method uses water as the solvent for the hydrochloric acid solution, and the precipitated product is flower-shaped AgCl, characterized by at least 12 petal-shaped dendrite protrusions growing from nucleation sites in a 1-5-5-1 pattern. However, this application yields symmetrical eight-arrowhead-shaped dendritic AgCl. The eight-arrowhead-shaped dendritic AgCl powder particles are composed of eight arrowhead-shaped dendrites symmetrically distributed in three-dimensional space, and these eight arrowhead-shaped dendrites are connected through a common nucleation site region, as shown in the examples. Figure 3-4 As shown.

[0029] The symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material involved in this application uses symmetrical eight-arrow-shaped dendritic AgCl as a carrier, with nano-Ag attached to its surface. Due to its symmetry, it has a large number of surface atoms with specific crystal plane distribution characteristics. This symmetrical eight-arrow-shaped dendritic AgCl / Ag composite material may have superior performance in photocatalysis, sterilization and disinfection. Attached Figure Description

[0030] Figure 1 The image shows a scanning electron microscope (SEM) image of the Cu-Ag nanoporous material prepared in Example 1.

[0031] Figure 2 The image shows the XRD diffraction pattern of the Cu-Ag nanoporous material prepared in Example 1.

[0032] Figure 3 The image shows a scanning electron microscope (SEM) image of the symmetrical eight-arrow-shaped dendritic AgCl / Ag material prepared in Example 1.

[0033] Figure 4 This is a high-magnification scanning electron microscope image of the symmetrical eight-arrow-shaped dendritic AgCl / Ag material prepared in Example 1.

[0034] Figure 5 The image shows the XRD diffraction pattern of the symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material prepared in Example 1. Specific implementation methods

[0035] Example 1

[0036] Raw materials were weighed according to an atomic percentage ratio of Ca:Mg:Cu:Ag = 2:1:1:1. Cu-Ag and Ca-Mg master alloys were smelted separately using an electric arc furnace and an induction furnace. Then, the Cu-Ag and Ca-Mg master alloys were smelted in an induction furnace to obtain a Ca-Mg-Cu-Ag master alloy. The Ca-Mg-Cu-Ag alloy was then passed through a copper roller spinning machine to obtain Ca... 40 Mg 20 Cu 20 Ag 20 (Atomic percentage) Amorphous alloy strips, strip thickness 20-30μm.

[0037] Ca 40 Mg 20 Cu 20 Ag 20 The amorphous alloy strip was placed in a 2.5 mol / L hydrochloric acid solution and reacted for 0.5 h to dissolve as much Ca and Mg as possible from the alloy strip. The result was as follows: Figure 1 The material shown is a Cu-Ag nanoporous material composed of Cu and Ag, with a total atomic percentage content of Cu and Ag exceeding 99%. The XRD pattern of the Cu-Ag nanoporous material is shown below. Figure 2 As shown.

[0038] 0.1g of the above Cu-Ag nanoporous material was placed in 100ml of a mixed solution of 12mol / L hydrochloric acid aqueous solution and ethanol in a volume ratio of 1:1. The temperature of the mixed solution was 60℃. Under ultrasonic assistance at 40KHZ and ultrasonic temperature of 60℃, the Cu-Ag nanoporous material was completely dissolved after 10min, resulting in a pale yellow intermediate solution.

[0039] Stop the sonication and allow the intermediate solution to cool naturally to room temperature. A white solid substance precipitates from the middle of the pale yellow solution. After separation, cleaning, and drying, symmetrical eight-arrow-shaped dendritic AgCl powder material is obtained.

[0040] Symmetrical eight-arrow-shaped dendritic AgCl powder was irradiated with ultraviolet light, causing some AgCl on the surface to decompose and nano-Ag particles to adhere to it, resulting in a powder with the following structure: Figure 3 The image shows a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material. A magnified photograph of it is shown below. Figure 4 As shown, the eight arrowhead-shaped dendrite AgCl powder particles are composed of eight arrowhead-shaped dendrites symmetrically distributed in three-dimensional space, and the eight arrowhead-shaped dendrites are connected by a common nucleation point region. Figure 5 The XRD pattern is shown for the prepared symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material.

[0041] Example 2

[0042] Raw materials were weighed according to an atomic percentage ratio of Ca:Mg:Cu:Ag = 2:1:1:1. Cu-Ag and Ca-Mg master alloys were smelted separately using an electric arc furnace and an induction furnace. Then, the Cu-Ag and Ca-Mg master alloys were smelted in an induction furnace to obtain a Ca-Mg-Cu-Ag master alloy. The Ca-Mg-Cu-Ag alloy was then passed through a copper roller spinning machine to obtain Ca... 40 Mg 20 Cu 20 Ag 20 (Atomic percentage) Amorphous alloy strips, strip thickness 20-30μm.

[0043] Ca 40 Mg 20 Cu 20 Ag 20 Amorphous alloy strips were placed in a 2 mol / L hydrochloric acid solution and reacted for 1 hour to dissolve as much of the Ca and Mg elements in the amorphous strips as possible, resulting in Cu-Ag nanoporous materials mainly composed of Cu and Ag elements. The total atomic percentage of Cu and Ag in the Cu-Ag nanoporous materials exceeded 99%.

[0044] 0.1g of the above Cu-Ag nanoporous material was placed in 100ml of a mixed solution of 12mol / L hydrochloric acid aqueous solution and ethanol in a volume ratio of 1.1. Under ultrasonic assistance at 40KHZ and ultrasonic temperature of 60℃, the Cu-Ag nanoporous material was completely dissolved after 12min, resulting in a pale yellow intermediate solution.

[0045] Stop the sonication and allow the intermediate solution to cool naturally to room temperature. A white solid substance precipitates from the middle of the pale yellow solution. After separation, cleaning and drying, symmetrical eight-arrow-shaped dendritic AgCl powder material is obtained.

[0046] Symmetrical eight-arrowhead-shaped dendritic AgCl powder material was irradiated with an electron beam, causing the surface AgCl to decompose and nano-Ag particles to adhere to it, resulting in symmetrical eight-arrowhead-shaped dendritic AgCl / Ag powder material. The eight-arrowhead-shaped dendritic AgCl powder particles consist of eight arrowhead-shaped dendrites symmetrically distributed in three-dimensional space, and these eight arrowhead-shaped dendrites are connected by a common nucleation point region.

[0047] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material, characterized in that, Includes the following steps: An amorphous initial alloy strip is provided, wherein the composition of the amorphous initial alloy strip is Ca. 40 Mg 20 Cu 20 Ag 20 The amorphous initial alloy strips were reacted with an acid solution to obtain Cu-Ag nanoporous material whose main components are Cu and Ag. Cu-Ag nanoporous material was reacted with an excess hydrochloric acid-ethanol solution under ultrasonic-assisted conditions. When the ultrasonic time exceeded 5 minutes, the Cu-Ag nanoporous material completely dissolved in the excess hydrochloric acid-ethanol solution, yielding a pale yellow, clear intermediate solution. The hydrochloric acid-ethanol solution was prepared by mixing 12 mol / L hydrochloric acid aqueous solution with ethanol, and the volume ratio of the 12 mol / L hydrochloric acid aqueous solution to ethanol ranged from 0.9 to 1.

1. The volume of the Cu-Ag nanoporous material was less than 1 / 200 of the volume of the hydrochloric acid-ethanol solution, ensuring a sufficient excess of the hydrochloric acid-ethanol solution. Stop the sonication. The white solid substance slowly precipitates from the pale yellow clear intermediate solution. Collect the white solid substance to obtain symmetrical eight-arrow-shaped dendritic AgCl powder particles. The surface portion of the symmetrical eight-arrow-shaped dendritic AgCl powder particles was photodecomposed to obtain nano-Ag particles, thus obtaining the symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material. The symmetrical eight-arrowhead dendrite AgCl powder particles are composed of eight arrowhead dendrites symmetrically distributed in three-dimensional space, and the eight arrowhead dendrites are connected by a common nucleation point region. The amorphous initial alloy strip is obtained by: preparing alloy raw materials according to atomic percentage and melting them to obtain an alloy melt, and preparing the alloy melt into amorphous initial alloy strips of 20-100μm by a copper roller spinning machine; The total atomic percentage content of Cu and Ag in the Cu-Ag nanoporous material exceeds 98%. The temperature of the hydrochloric acid ethanol solution is 60℃-100℃.

2. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The ultrasound time is more than 5 minutes and less than 30 minutes.

3. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The volume ratio of the 12 mol / L hydrochloric acid aqueous solution to ethanol is 1.

4. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The frequency of the ultrasound is 40-80 kHz.

5. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The volume of the Cu-Ag nanoporous material is less than 1 / 1000 of the volume of the hydrochloric acid ethanol solution.

6. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The surface portion of the symmetrical eight-arrow-shaped dendritic AgCl powder particles is photodecomposed into nano-Ag particles by at least one of sunlight, electron beam, and ultraviolet irradiation.

7. The method for preparing a symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material according to claim 1, characterized in that, The symmetrical eight-arrow-shaped dendritic AgCl / Ag powder material has symmetrical eight-arrow-shaped dendritic AgCl particles with a size of 0.5μm-8μm, and the nano Ag particles have a size of 2nm-50nm.

Images