Nuclear shell nanometer catalyst packaged with noble metal nanometer grains and method thereof

Abstract

The invention relates to a nuclear shell nanometer catalyst packaged with noble metal nanometer grains and a method thereof, which relate to a nanometer catalyzing material. The invention provides a nuclear shell nanometer catalyst packaged with noble metal nanometer grains, which has a size of the noble metal grains less than 10nm, and higher contact level among noble metal grains and stability of the catalyst, can be reused and is adaptive to different using conditions by multi-level derivation, and also provides a preparation method thereof. The catalyst has a formula of NMP@X, NMP is nanometer grains such as Pd, AgPd or Au, and the like, and X is spherical SiO2, hollow SnO2 ball or hollow C ball. The method comprises the following steps: synthesizing noble metal nanometer grains and adorning the surface to obtain noble metal-iron oxide nanometer heterojunction; coating a silicon dioxide to obtain noble metal iron heterojunction oxide @ silicon dioxide nuclear shell nanometer material, growing porous pores on the surface, removing the silicon dioxide, and removing iron oxide on the noble metal nanometer grains so that the noble metal nanometer grains are located in a nanometer capsule of the hollow porous pores to obtain the product.

Description

technical field [0001] The invention relates to a nano catalytic material, in particular to a core-shell nano catalyst wrapped with noble metal nano particles and a method thereof. Background technique [0002] Precious metals (including gold, silver, platinum, palladium, etc.) are good catalyst materials and have become the objects of social concern. Gold was considered to be a chemically inert substance for a long time and was thus ignored. Since Haruta (M.Haruta, N.Yamada, T.Kobayashi, S.Iijima Gold catalysts prepared by coprecipitation for low-temperature oxidation of hydrogen and of carbon monoxide. Journal of Catalysis, 1989.115 (2): 301-309) etc. in In the 1980s, after discovering that the CO oxidation reaction of gold nano-loaded materials had a high-efficiency catalytic function at low temperature, Goodman (A.Kolmakov, D.W.Goodman Scanning tunneling microscopy of gold clusters TiO 2 (110): CO oxidation at elevated pressures. Surface Science. 2001.490 (1): 597-601)...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to aim at the poor stability of supported noble metal nano catalysts, easy aggregation and growth, loss of noble metal elements during use, and chemical affinity mismatch between noble metal nanomaterials and silicon dioxide, so far no less than Insufficient core-shell structure of 10nm-sized noble metal particles provides a noble metal particle size less than 10nm, mutual contact between noble metal particles, high stability of the catalyst, which can ensure the recycling of the catalyst, and can be adapted to different Core-shell nanocatalyst wrapped noble metal nanoparticles and preparation method thereof under conditions of use

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