CN-121976235-A - Preparation method and application of copper/cuprous oxide heterostructure material

Abstract

The invention belongs to the technical field of nano material preparation, and particularly relates to preparation and application of a copper/cuprous oxide heterostructure material. The method adopts a metal organic precursor mediation strategy to prepare the copper/cuprous oxide heterostructure material, and has important application value for electrochemical nitrate reduction of synthetic ammonia. When the material is used as a catalyst, the material has higher ammonia production rate and Faraday efficiency on nitrate reduction synthesis ammonia under alkaline conditions. The method is simple, the raw materials are easy to obtain, the practical value is high, and the method has important significance for the design and preparation and application of the catalyst.

Inventors

• TAN ZHENQUAN
• LIU XINGJIA
• SONG XUEZHI

Assignees

• 大连理工大学

Dates

Publication Date

20260505

Application Date

20260130

Claims (8)

1. 1. The preparation method of the copper/cuprous oxide heterostructure material is characterized by comprising the following steps of: Dissolving copper salt and a surfactant in water, uniformly stirring to obtain a metal salt solution, dissolving an organic ligand in a solvent, then adding the organic ligand into the metal salt solution, uniformly stirring, and obtaining a metal organic precursor nano material by a solvothermal method; and step two, under the protection of inert atmosphere, the metal organic precursor nano material obtained in the step one is placed in a tube furnace to be calcined, and the copper/cuprous oxide heterostructure material is obtained.
2. 2. The preparation method of the copper/cuprous oxide heterostructure material according to claim 1, wherein in the first step, the molar ratio of copper salt to organic ligand is (40-60): (20-40), and the molar ratio of copper salt to surfactant is (40-60): (30-50).
3. 3. The preparation method of the copper/cuprous oxide heterostructure material according to claim 1, wherein the copper salt is one or more than two of copper nitrate, copper chloride and copper acetate, the organic ligand is one or more than two of trimesic acid, thiophene dicarboxylic acid, benzene tetracarboxylic acid and L-aspartic acid, and the surfactant is one or more than two of cetyl trimethyl ammonium bromide, polyvinylpyrrolidone and polyethylene glycol.
4. 4. The method for preparing a copper/cuprous oxide heterostructure material according to claim 1, wherein in the solvothermal method in the step one, the heating temperature is 80-140 ℃, and the reaction time is 1-5 hours.
5. 5. The method for preparing the copper/cuprous oxide heterostructure material according to claim 1, wherein the calcining temperature in the second step is 200-600 ℃ and the calcining time is 1-4 h.
6. 6. The copper/cuprous oxide heterostructure material prepared by the method of any of claims 1-5 has a coral-like structure.
7. 7. The use of the copper/cuprous oxide heterostructure material prepared by any of claims 1-5 as a catalyst in nitrate reduction synthesis of ammonia.
8. 8. The use according to claim 7, characterized by the following specific procedures: Putting copper/cuprous oxide heterogeneous nano material catalyst into a centrifuge tube, adding deionized water, isopropanol and Nafion solution, uniformly mixing, performing ultrasonic treatment to obtain ink, uniformly coating the prepared ink on carbon paper, coating 0.2-0.4 mg of copper/cuprous oxide heterogeneous nano material catalyst on each square centimeter of carbon paper, drying at room temperature to obtain an electrode, putting the prepared electrode into an electrolytic cell, taking a platinum sheet as a counter electrode, taking a silver/silver chloride electrode as a reference electrode, taking a mixed solution of potassium hydroxide and potassium nitrate as electrolyte, and reducing nitrate radical into ammonia.

Description

Preparation method and application of copper/cuprous oxide heterostructure material Technical Field The invention belongs to the technical field of nano material preparation, and particularly relates to preparation and application of a copper/cuprous oxide heterostructure material. Background Ammonia, an indispensable chemical raw material, plays a significant role in many industries such as agriculture, chemical industry, pharmacy, and textiles. In addition, in view of the high energy density and hydrogen-rich nature of ammonia, its potential in the energy field is also of great interest, as a very promising carbon-free energy carrier. Currently, industrial ammonia synthesis mainly relies on the haber-bosch process. However, this process has significant drawbacks in that the reaction is carried out under high temperature, high pressure conditions, which results in extremely high energy consumption, which is statistically 2% of the global power consumption. Under the severe situation, water is taken as a proton source, and the technical path for preparing ammonia by means of electrocatalytic nitrate reduction is focused in recent years because the reaction conditions are mild, and the ammonia can be well compatible with renewable energy sources such as solar energy, wind energy and the like. Electrochemical nitrate reduction involves a complex process of 8 electrons and 9 protons, involves a number of intermediates and products, and therefore development of high-performance electrocatalytic materials, efficient selective reduction of nitrate to ammonia, is of great importance. Although noble metal-based catalysts exhibit excellent performance in electrocatalytic nitrate reduction reactions, their high cost and scarce reserves have greatly limited large-scale popularization and application. Therefore, the transition metal copper-based catalyst with abundant reserves and low cost becomes a research and development hot spot. However, it is difficult to provide active hydrogen atoms required for catalytic reaction at a single copper site, and the catalytic performance of copper varies from nitrate reduction reaction to nitrate reduction reaction, resulting in low catalytic activity and selectivity of copper-based catalysts. In addition, the Metal Organic Frameworks (MOFs) material can realize the spatial separation of catalytic sites, promote the transmission of substances and promote the catalytic activity due to the porous structure formed by coordination of metal clusters and organic ligands and the characteristic of high specific surface area. And MOFs structure and composition are easy to customize, can be flexibly designed and regulated, and create favorable conditions for enriching NO 3- and stabilizing reaction intermediates. At present, a great deal of research combines transition metal copper-based materials with MOFs materials, regulates and controls the surface microstructure and active center electronic structure of the copper-based materials, and improves the catalytic performance of the copper-based materials in electrochemical nitrate radical reduction reaction. For the single copper center material, the active hydrogen mediated reduction path is difficult to occur, most of the existing researches and technologies use the transition metal cerium or cobalt center to optimize the active hydrogen mediated reduction path, so that the catalytic process is promoted to a certain extent, and a new center needs to be introduced to optimize the structure to realize further improvement of the catalytic performance. And few studies are currently underway to convert copper sites to cuprous sites. Disclosure of Invention The invention aims to provide a preparation method and application of a copper/cuprous oxide heterostructure material, and the preparation method adopts a metal organic precursor mediated strategy to prepare the copper/cuprous oxide heterostructure material, so that the preparation method has a critical application value for electrochemical nitrate reduction synthesis of ammonia. When the material is used as a catalyst, the material has higher ammonia production rate and Faraday efficiency on nitrate reduction synthesis ammonia under alkaline conditions. In order to achieve the above purpose, the present invention adopts the following technical scheme: the preparation method of the copper/cuprous oxide heterostructure material comprises the following steps: Dissolving copper salt and a surfactant in water, uniformly stirring to obtain a metal salt solution, dissolving an organic ligand in a solvent, then adding the organic ligand into the metal salt solution, uniformly stirring, and obtaining a metal organic precursor nano material by a solvothermal method; and step two, under the protection of inert atmosphere, the metal organic precursor nano material obtained in the step one is placed in a tube furnace to be calcined, and the copper/cuprous oxide heterostructure material is obtained. Prefe