Cobalt/noble metal/cobalt hydroxide nano-composite material, and preparation method and application thereof

Abstract

The invention relates to a cobalt / noble metal / cobalt hydroxide nano-composite material, and a preparation method and the application thereof. The cobalt / noble metal / cobalt hydroxide nano-composite material has magnetic core-shell structures; the surfaces of the magnetic core-shell structures are of ball-flower shapes; the average particle size is 170 to 220 nm; the cores are cobalt nano-particles; noble metal shell layers coat the cobalt nano-particles; the outmost layers are cobalt hydroxide protective layers. The preparation method comprises the following steps: mixing divalent cobalt salt or a solution of the divalent cobalt salt and polyvinylpyrrolidone; introducing argon gas for protecting over 30 minutes, reacting the mixture with a sodium borohydride solution, reacting the product with a solution of noble metal salt, and performing centrifugal separation on products. The composite material prepared by the method has high purity, a special structure, high activity and magnetic performance and high stability, and can be effectively applied to organic catalytic reaction; the preparation method is simple, continuous and controllable, mild in conditions, low requirement on equipment, and suitable for industrial production.

Description

technical field [0001] The invention relates to the technical field of nanocomposite materials, in particular to a preparation method and application of a cobalt / noble metal / cobalt hydroxide nanocomposite material. Background technique [0002] In the upsurge of research on nanomaterials, the unique optical, electrical, and catalytic properties of metal nanomaterials and their applications in new energy research, biomedicine, and other fields have attracted extensive attention in related research fields. In particular, noble metal nanostructures (Au, Pd, and Pt, etc.) have excellent catalytic performance, showing amazing application value and potential. Compared with single metal nanomaterials, metal core-shell composites have excellent catalytic performance and high stability. In addition, by encapsulating magnetic cobalt nanoparticles with noble metal nano-core-shell materials, not only can the synergy between the core and the shell be used to improve the performance of t...

AI Technical Summary

Problems solved by technology

However, in the research on the catalytic application of materials, we found that there are still some relatively prominent problems that need to be solved urgently: First, because the magnetic core has a certain strength of magnetism, the core-shell materials are easier to aggregate than the single-shell materials, resulting in catalytic During the process, the active sites of the catalyst are reduced; secondly, the core-shell material is directly exposed to the reaction solvent, the noble metal shell material is easily eroded, and the stability of the catalyst is not very ideal

At present, there have been cases of successfully compounding a carbon layer or a silicon dioxide layer on the surface of metal particles. Although the purpose of protecting the core metal material is achieved, the synthesis process is complicated and does not have continuity.

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