CN-116590775-B - Preparation method of copper-based nanomaterial rich in two-dimensional defects and electrocatalytic CO (carbon monoxide) prepared by preparation method2Application in reduction

CN116590775BCN 116590775 BCN116590775 BCN 116590775BCN-116590775-B

Abstract

The invention discloses a preparation method of a copper-based nanomaterial rich in two-dimensional defects and application of the copper-based nanomaterial in electrocatalytic CO 2 reduction, wherein in the process of preparing the copper-based nanomaterial by electrochemical deposition, the copper-based nanomaterial is induced to form the two-dimensional defects by doping halogen (F, cl, br and I), so that the copper-based nanomaterial rich in the two-dimensional defects is obtained. According to the invention, halogen elements are well doped into the copper nanomaterial through an electrochemical deposition process, different defects and active sites are induced, the adsorption capacity of a reaction intermediate is enhanced, the conversion efficiency of electrocatalytic reduction carbon dioxide (eCO 2 RR) to a multi-carbon (C 2+ ) product is improved, and the type and the size of the generated defects are changed by adjusting the type and the concentration of halide in the electrolyte.

Inventors

WANG YAN
LUO JIE
WU YUCHENG
ZHANG JIANFANG
YU CUIPING
QIN YONGQIANG
ZHANG YONG

Assignees

合肥工业大学

Dates

Publication Date: 20260505
Application Date: 20230517

Claims (5)

1. The preparation method of the copper-based nanomaterial rich in two-dimensional defects is characterized in that in the process of preparing the copper-based nanomaterial by electrochemical deposition, the copper-based nanomaterial is induced to form the two-dimensional defects by halogen doping, and the copper-based nanomaterial rich in the two-dimensional defects is obtained; f doping induces the copper-based nano material to form twin crystal boundary defects and stacking fault defects, cl doping induces the copper-based nano material to form stacking fault defects, and Br doping or I doping induces the copper-based nano material to form crystal boundary defects.
2. The method for preparing the copper-based nanomaterial rich in two-dimensional defects as claimed in claim 1, wherein the concentration of the potassium hydroxide solution is 1.0-4.0 mol/L.
3. The method for preparing the copper-based nanomaterial rich in two-dimensional defects as claimed in claim 1, wherein the concentration of halide in the electrolyte is 0.1-1.0 mol/L.
4. A copper-based nanomaterial enriched in two-dimensional defects produced by the method of any one of claims 1 to 3.
5. Use of the two-dimensional defect-rich copper-based nanomaterial of claim 4 in electrocatalytic CO 2 reduction.

Description

Preparation method of copper-based nanomaterial rich in two-dimensional defects and application of copper-based nanomaterial in electrocatalytic CO 2 reduction Technical Field The invention relates to the technical fields of material science and electrocatalysis, in particular to a method for preparing a copper-based nanomaterial rich in two-dimensional defects by doping halogen elements. Background With the development of industrialization, excessive consumption of fossil fuels causes an increasing accumulation of CO 2 in the atmosphere, resulting in environmental problems and energy crisis. Electrocatalytic carbon dioxide reduction reactions in combination with renewable energy sources to produce value-added fuels and chemicals are potential strategies to achieve carbon-neutral energy recycling. The copper-based catalyst has unique capability of converting CO 2 into a multi-carbon product and higher activity and selectivity. The activity and selectivity of copper-based catalysts can be regulated by defect engineering, and the introduction of defects in copper can create a large number of active sites for adsorption of reactants and reaction intermediates. The free energy barrier of the intermediate in the reduction process of CO 2 can be reduced by introducing various two-dimensional defects (grain boundaries, twin boundaries, stacking faults and the like) into copper through chemical and electrochemical methods. The non-metal heteroatom halogen elements are doped into Cu crystal lattices, so that lattice mismatch and dislocation on the Cu surface can be induced, a large number of two-dimensional defects are generated, and the doping halogen content is different, so that the doping defect types and sizes of halogen atoms in Cu can be influenced. During electrochemical reduction reactions, catalytic materials of halogen doped metal oxides tend to undergo structural evolution and compositional changes at cathodic potential. The electrochemical reconstruction process can induce a plurality of defect active sites on the Cu surface, which is favorable for the adsorption and stabilization of reaction intermediates, thereby enhancing the performance of eCO 2 RR. Although there are many studies on doping halogen elements on the copper surface reported at present, a doping method by a one-step electrochemical deposition method has not been reported before. Disclosure of Invention The invention aims to provide a preparation method of a copper-based nanomaterial rich in two-dimensional defects, which is characterized in that halogen elements are doped in an electrochemical deposition process, and the concentration of halides in electrolyte is regulated so as to obtain more defects and active sites, so that high selectivity and stability are realized in an electrocatalytic carbon dioxide reduction reaction (eCO 2 RR). In order to achieve the purpose, the invention adopts the following technical scheme: A preparation method of a copper-based nanomaterial rich in two-dimensional defects is characterized in that in the process of preparing the copper-based nanomaterial by electrochemical deposition, the copper-based nanomaterial is induced to form the two-dimensional defects by halogen doping, and the copper-based nanomaterial rich in the two-dimensional defects is obtained. Further, the two-dimensional defects include twin boundary defects (TB), stacking fault defects (SF), and grain boundary defects (GB). The type of the two-dimensional defect formed is regulated by regulating the type of the doped halogen. F doping induces the copper-based nano material to form twin crystal boundary defects and stacking fault defects, cl doping induces the copper-based nano material to form stacking fault defects, and Br doping or I doping induces the copper-based nano material to form crystal boundary defects. The preparation method of the copper-based nanomaterial rich in the two-dimensional defects specifically comprises the steps of taking high-purity copper foil as an anode, taking carbon paper as a cathode, taking potassium hydroxide solution added with halides as electrolyte, applying current to be 170-210 mA, reacting for 0.5-1 hour, taking out the carbon paper, cleaning and drying to obtain the copper-based nanomaterial rich in the two-dimensional defects. Preferably, the concentration of the potassium hydroxide solution is 1.0 to 4.0mol/L. Preferably, the concentration of the halide in the electrolyte is 0.1 to 1.0mol/L. The halide may specifically be NH 4F、NH4Cl、NH4Br、NH4 I. Compared with the prior art, the invention has the beneficial effects that: 1. According to the invention, halogen elements are well doped into the copper nanomaterial through an electrochemical deposition process, different defects and active sites are induced, the adsorption capacity of a reaction intermediate is enhanced, the conversion efficiency of eCO 2 RR to a C 2+ product is improved, and the type and the size of the generated defects are chang