Method for universally preparing high-entropy alloy nanoparticles

Abstract

The invention discloses a universal preparation method of high-entropy alloy nanoparticles and application of the high-entropy alloy nanoparticles in thermocatalytic selective hydrogenation and acidicelectrolyzed water anode catalysis. Various alloys and high-entropy alloy nanoparticles can be prepared by utilizing a surface metal organic salt pyrolysis reduction method, metal organic salt is dispersed on the surface of a carrier in a molecular manner to form a metal organic salt film , an organic ligand is thermally decomposed to expose isolated metal atoms, and multi-component metal atoms are aggregated to form the uniform high-entropy alloy nanoparticles. According to the PtIrFeCoNi / XC-72 high-entropy alloy nanoparticles prepared in the embodiment of the method, the service life of PtIrFeCoNi / XC-72 is close to three times of the service life of commercial IrO2 under the extreme condition of the current density of 50mA / cm<2>; and therefore, it is shown that the high-entropy alloy has high stability and corrosion resistance, so that the high-entropy alloy nanoparticles become one of the most competitive catalysts in the acidic oxygen evolution reaction. The method for nanocrystallization of the high-entropy alloy has the advantages that universality is achieved, the method is simple and easy to implement, equipment is simple, and the carrier can be replaced and removed, and anew way and a new thought are provided for application of the high-entropy alloy nanoparticles to the fields of catalysis, energy, the environment and the like.

Description

technical field [0001] The invention belongs to the technical field of nanomaterials and catalysis, and in particular relates to a method for universally preparing high-entropy alloy nanoparticles and its application in the field of catalysis. Background technique [0002] High-entropy alloys (High-entropy alloys, HEA) are solid solutions with high entropy values ​​formed by atoms of equal or approximately equal amounts of five or more elements. High-entropy alloys have been widely studied and applied in the field of structural materials due to their high strength (fracture resistance), high toughness (deformation resistance), high temperature resistance, wear resistance, corrosion resistance and oxidation resistance. The high entropy effect, hysteretic diffusion effect, lattice distortion effect and cocktail effect of high entropy alloys provide theoretical support and guidance for their application in the field of functional materials (catalysis, energy and environment, et...

AI Technical Summary

Problems solved by technology

However, high-entropy alloys prepared by traditional processes such as vacuum melting and powder metallurgy are often bulk materials, which are difficult to apply in the fields of catalysis, energy, and environment, and the preparation process is relatively complicated and the cost is high.

The first step in the application of high-entropy alloys to functional materials is to realize their nanoscale preparation. The difficulty in the preparation of high-entropy alloy nanoparticles is mainly that the physical and chemical properties of each component metal are quite different, prone to phase separation, and difficult to uniformize in size. , during the high-temperature preparation process, metal atoms are easy to migrate to form particles with large particle sizes, and the size is difficult to control

In recent years, researchers have developed carbon-thermal oscillation method, electrodeposition method, dipping pen photolithography method and fast moving bed pyrolysis method to prepare high-entropy alloy nanoparticles. These methods have more or less shortcomings, such as the preparation requires special Equipment, difficulty in macro preparation and cumbersome operation, etc.

[0003] At present, the use of renewable energy to electrolyze water to produce high-purity hydrogen is an important way to solve the hydrogen source in the "hydrogen economy". Among them, the proton exchange membrane electrolysis water technology (PEM) has a wide working range and extremely short response time. Time and other characteristics have been paid great attention by researchers. The biggest technical obstacle restricting the application of this technology is the oxygen evolution catalyst that works stably for a long time in acidic electrolyte. The loss of active components due to corrosion is the main cause of catalyst deactivation

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