Preparation method of copper selenide and nickel core-shell heterostructure nano array
By preparing core-shell heterostructure nanoarrays of copper selenide and nickel selenide, the problems of high energy consumption and high pollution in traditional ammonia preparation are solved, and an efficient and environmentally friendly electrocatalytic reduction ammonia preparation process is achieved.
Patent Information
- Application Number
- CN202510600832.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-12
- Publication Date
- 2025-08-12
AI Technical Summary
In the prior art, selenide research mainly focuses on high hardness, high melting point, high chemical stability and excellent thermoelectric properties. There is little research on transition metal selenide, and the traditional ammonia preparation method has high energy consumption and high pollution, and lacks efficient and environmentally friendly electrocatalysts.
The copper hydroxide precursor was prepared by anodizing method, combined with tube furnace heat treatment and electrochemical deposition, a core-shell heterostructure nanoarray of copper selenide and nickel selenide was prepared as an electrocatalyst for ammonia reduction.
It realizes a high-purity, uniformly distributed nanoarray, has good electrocatalytic reduction capability, is suitable for large-scale industrial production, and avoids traditional preparation methods that are high energy consumption and high pollution.
Smart Images
Figure CN120465048A_ABST
Abstract
Description
Technical Field
[0001] The patent of this invention relates to the technical field of preparation of core-shell heterostructures of copper selenide and nickel, and specifically to a method for preparing a core-shell heterostructure of copper selenide and nickel as an electrocatalyst for nitrate reduction to produce ammonia. Technical Background
[0002] To date, research on selenides has mainly focused on materials with high hardness, high melting point, high chemical stability and excellent thermoelectric properties (such as metal selenides such as Bi2Se3, SnSe, Sb2Se3 and PbSe). There is less research on selenides of some transition metals (Cr, Fe, Co, Ni and Cu, etc.), and current research is mainly applied in the field of hydrogen production by water electrolysis. Because the probability of direct combination of metals and selenium elements is small, there is less attention paid to these metal selenides bound by covalent bonds.
[0003] The copper nitride unit cell belongs to the face-centered cubic (fcc) structure, the space group is Fm-3m, Se 2- Constitute the fcc skeleton, Se atoms occupy the vertices and face center positions of the fcc lattice, forming a rigid framework. + Ions are located in interstitial positions (tetrahedral or octahedral positions), and there are a large number of dynamic vacancies, resulting in a high degree of disorder in the sublattice. Cu ions can migrate freely, resulting in extremely high ionic conductivity. Cu atoms occupy the center of the cubic unit cell edge, and N atoms occupy the vertices of the cubic unit cell. Since Cu atoms fail to occupy the tightly packed position of the lattice (111) plane, many gaps are left in the cubic structure, making this structure extremely special. When Cu atoms or other atoms fill these gaps, it will cause significant changes in the optical and electrical properties of the film.
[0004] Copper selenide is a compound with mixed ionic and metallic bonds. + with Se 2- The main bond between them is ionic, and the Cu-Cu metal bond contributes to conductivity. Due to the superionicity and defect tolerance of its own structure, it is irreplaceable in the fields of thermoelectricity and energy. Copper selenide is a non-toxic and stable raw material.
[0005] Copper selenide is stable at room temperature in air, but oxidizes violently at 300°C in oxygen. It begins to decompose at about 500°C in a vacuum. It dissolves in dilute nitric acid to form Cu 2+ It can decompose violently with H2Se in concentrated sulfuric acid and concentrated nitric acid, and has strong alkali resistance.
[0006] The nickel unit cell has a face-centered cubic (fcc) structure with a space group of Fm-3m. Ni atoms occupy the vertices and face-center positions of the fcc lattice, forming a tightly packed structure. In the nickel fcc structure, the (111) plane is the closest packed plane, with an atomic filling rate of up to 74%, no significant voids, and extremely low defect concentration at room temperature.
[0007] Nickel is a typical transition metal composed of metallic bonds, characterized by its high symmetry and close stacking, which gives it excellent mechanical strength, conductivity and stability. Nickel is a non-toxic and stable raw material.
[0008] Ammonia, as a widely used chemical raw material, can be used in hydrogen storage, chemical industry, agriculture and other fields. It has always been considered the cornerstone of chemical and agricultural development to meet the world's growing scientific and technological needs. However, traditional ammonia evolution is mainly obtained through the Haber-Bosch process, which is usually accompanied by high energy input, huge CO2 emissions and other toxic wastes. The electrocatalytic reduction of nitrate in wastewater to ammonia with higher value can avoid this high energy consumption and high pollution preparation method. Therefore, copper and nickel, as elements with high earth abundance, have become better choices. The use of copper selenide as an electrocatalyst for electrochemical nitrate reduction has also become a very promising environmentally friendly technology. Summary of the Invention
[0009] To solve the above problems, the present invention provides a method for preparing a copper selenide and nickel core-shell heterostructure nanoarray with a simple method, high purity, low oxygen content, and a complete and uniform nanoarray.
[0010] The technical solution adopted in the present invention is:
[0011] A method for preparing a copper selenide and nickel core-shell heterostructure nanoarray comprises the following steps:
[0012] (1) A precursor is prepared on the surface of the pre-cleaned copper foam by an anodic oxidation method; the prepared precursor is dried in a blast drying oven at 60° C. overnight.
[0013] (2) Two pieces of precursors were placed in a quartz boat, which was placed downstream of the quartz tube of the tube furnace. A certain amount of selenium powder was weighed and placed in another quartz boat, which was placed upstream of the tube furnace. The tube furnace was sealed and argon was continuously introduced. The temperature was raised to a certain temperature at 10 °C / min. After keeping the temperature for a period of time, the temperature was naturally cooled to room temperature. The sample was rinsed with pure water and alcohol several times and then dried in a blast drying oven at 60 °C for 2 h to obtain Cu 2-x Se@CF nanoarray.
[0014] (2) Place a piece of Cu 2-xSe@CF was used as the working electrode, Ag / AgCl and carbon rod were used as the reference electrode and counter electrode respectively. They were placed in a solution containing a certain concentration of nickel chloride and ammonium chloride. After a period of time at a certain voltage, the sample was washed with pure water and alcohol several times and dried in a blast drying oven at 60°C for 2 hours to obtain Ni@Cu 2-x Se@CF nanoarray.
[0015] As a preferred method, the anodic oxidation method is as follows: CF is pre-cleaned by soaking in 2M HCl for 10 minutes, and then rinsed with water and ethanol for 3 times. 2 ) was immersed in 1 M KOH solution, and each side of the CF was charged at 10 mA cm in a two-electrode setup. -2 Anodize for 10 min. After anodization, rinse the sample with water and dry it in an oven before further experiments.
[0016] Preferably, the precursor is Cu(OH)2, denoted as Cu(OH)2@CF.
[0017] Preferably, the amount of selenium powder is 1000 mg.
[0018] Preferably, the argon gas flow rate is 20 ml min -1 .
[0019] Preferably, the temperature is 400°C.
[0020] Preferably, the holding time is 60 minutes.
[0021] Preferably, the electrolyte concentration is a mixed solution of 0.1M nickel chloride and 0.1M ammonium chloride.
[0022] Preferably, the deposition voltage is -1V vs Ag / AgCl.
[0023] Preferably, the deposition time is 15 minutes.
[0024] Preferably, the room temperature is 15-35°C.
[0025] Beneficial effects of the present invention:
[0026] The method is simple, resulting in uniform nanoarray distribution and high-purity copper selenide. Furthermore, copper selenide, as an electrocatalyst, exhibits excellent electrocatalytic reduction capabilities. The temperature ramp-up schedule employed in the present invention ensures a safe and orderly reaction, preventing safety concerns and nanoarray shedding due to rapid temperature increases. The entire reaction is simple to operate and can be implemented in large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the features, technical means and specific objectives and functions achieved by the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:
[0028] Figure 1 Flowchart for implementing the experiment.
[0029] Figure 2 The XRD pattern shows the effect of reaction temperature of 400°C on the generated products.
[0030] Figure 3 The ×5000 SEM image shows the effect of reaction temperature of 400°C on the generated products.
[0031] Figure 4 The XRD pattern shows the effect of reaction voltage -1V vs Ag / AgCl on the generated products.
[0032] Figure 5 The ×5000 SEM image shows the effect of the reaction voltage of -1V vs Ag / AgCl on the generated products.
[0033] Figure 6 The LSV diagram shows the effect of the above reaction conditions on the generated products. DETAILED DESCRIPTION
[0034] Implementation Plan
[0035] Experimental materials and instruments
[0036] Experimental materials: copper foam (Kunshan Guangjiayuan New Materials Co., Ltd.), potassium hydroxide (Beijing Inokai Technology Co., Ltd.), selenium powder (Aladdin (Shanghai) Chemical Reagent Co., Ltd.), argon (Kaifeng Wantong Gas Co., Ltd.).
[0037] Experimental instruments: CS235OH electrochemical workstation (Wuhan Koster), tube furnace (1200X, Hefei Kejing Material Technology Co., Ltd.), drying oven, electronic balance, other glass instruments, etc.
[0038] (1) The copper foam that had been cleaned in advance was used to prepare copper hydroxide on its surface by anodization. The specific operation steps were as follows: a piece of copper foam was used as the working electrode, and a piece was used as the counter electrode and reference electrode. The electrolyte was 1M KOH and the current was 10 mA cm -2 The constant current deposition was performed for 20 min. After the deposition was completed, the prepared Cu(OH)2 / CF was rinsed with pure water and anhydrous ethanol for several times, and then the prepared Cu(OH)2 / CF was dried in a forced air drying oven at 60°C overnight.
[0039] (2) Place two pieces of Cu(OH)2 / CF in a quartz boat, and place it downstream of the quartz tube of the tube furnace. Weigh 1000 mg of selenium powder and place it in another quartz boat, and place it upstream of the quartz boat of the tube furnace. Seal the tube furnace and continuously introduce argon at a flow rate of 20 ml / min. -1 The temperature was raised to 400℃ at 10℃ / min, kept at this temperature for 60min, and cooled naturally. The sample was rinsed with pure water and alcohol several times and then dried in a blast drying oven at 60℃ for 2h to obtain Cu 2-x Se@CF nanoarray.
[0040] (3) Place a piece of Cu 2-x Se@CF was immersed in a solution containing 0.1M nickel chloride and 0.1M ammonium chloride, with copper selenide as the working electrode, carbon rod as the counter electrode, and silver / silver chloride electrode as the reference electrode, at a voltage of -1V vs Ag / AgCl for 15min. The obtained sample was rinsed with pure water and alcohol several times and dried in a 60℃ forced air drying oven for 2h to obtain Ni@Cu 2-x Se@CF nanoarray
[0041] Finally, it should be noted that the above embodiments are only used for the technical solutions of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above examples, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for the technical features therein, and these modifications or replacements do not deviate the essence of the technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for preparing a copper selenide and nickel core-shell heterostructure nanoarray, characterized in that: The following steps are involved: (1) The copper foam that had been pre-cleaned was used to prepare copper hydroxide on its surface by anodization. The specific operation steps were as follows: one piece of copper foam was used as the working electrode, the other piece of copper foam was used as the counter electrode, the electrolyte was 1 M KOH, and the flow rate was 10 mA cm -2 The constant current deposition was performed for 20 min. After the deposition was completed, the prepared Cu(OH)2 / CF was soaked and rinsed with high-purity water and anhydrous ethanol for multiple times, and then the prepared Cu(OH)2 / CF was dried in a forced air drying oven at 60°C for 2 h. (2) Place two pieces of Cu(OH)2 / CF in a quartz boat, and place it downstream of the quartz tube of the tube furnace. Weigh 1000 mg of selenium powder and place it in another quartz boat, and place it upstream of the tube furnace. Seal the tube furnace and continuously introduce argon at a flow rate of 20 ml min. -1 The temperature was raised to 400℃ at 10℃ / min, kept at this temperature for 60min, and cooled naturally. The obtained sample was rinsed with pure water and alcohol several times and then dried in a blast drying oven at 60℃ for 2h to obtain Cu 2-x Se@CF nanoarray. (3) A thin nickel layer is prepared on the surface of the pre-prepared copper selenide by constant voltage electroreduction method to form a heterogeneous nanostructure; the specific operation steps are: 2-x Se@CF was immersed in a solution containing 0.1M nickel chloride and 0.1M ammonium chloride, with copper selenide as the working electrode, carbon rod as the counter electrode, and silver / silver chloride electrode as the reference electrode, at a voltage of -1VvsAg / AgCl for 15min. The obtained sample was rinsed with pure water and alcohol several times and then dried in a blast drying oven at 60℃ for 2h to obtain Ni@Cu 2-x Se@CF nanoarray.
2. The method for preparing a copper selenide and nickel core-shell heterostructure nanoarray according to claim 1, characterized in that: The copper selenide precursor was prepared by anodic oxidation on its surface to form Cu(OH)2 nanoarrays. The specific operation steps were as follows: a piece of copper foam was used as the working electrode, a piece as the counter electrode, the electrolyte was 1M KOH, and the flow rate was 10mA·cm -2 The constant current deposition was performed for 20 min. After the deposition was completed, the prepared Cu(OH)2 / CF was rinsed with pure water and anhydrous ethanol for multiple times, and then the prepared Cu(OH)2 / CF was dried in a forced air drying oven at 60°C overnight to obtain Cu(OH)2 / CF.
3. The method for preparing a copper selenide and nickel core-shell heterostructure nanoarray according to claim 1, characterized in that: Selenium powder is used as a selenium source, selenization is completed at a relatively low temperature, and a uniform copper selenide nanoarray is directly obtained.
4. The method for preparing a copper selenide and nickel core-shell heterostructure nanoarray according to claim 1, characterized in that: The argon flow rate was 20 ml min -1 .
5. The method for preparing a copper selenide and nickel core-shell heterostructure nanoarray according to claim 1, characterized in that: Nickel ions are used as the nickel source, and reduction is completed under a certain voltage to directly obtain a uniform copper selenide and nickel core-shell heterostructure nanoarray.
6. The method for preparing a copper selenide and nickel core-shell heterostructure nanoarray according to claim 1, characterized in that: The applied potential was -1 V vs Ag / AgCl.