Mesoporous silicon dioxide material with eggshell-yolk structure and preparation method of mesoporous silicon dioxide material

Abstract

The invention provides a mesoporous silicon dioxide material with an eggshell-yolk structure and a preparation method of the mesoporous silicon dioxide material. The material is in a spherical shape as a whole, and the specific surface area is 500-800 m<2> / g. The ''yolk'' is a silicon dioxide solid sphere with a diameter of 200-500 nm, the ''eggshell'' is a silicon dioxide hollow sphere with a thickness of 20-100 nm, the diameter of a cavity is 240-800 nm, the ''eggshell'' and the ''yolk'' have regular ordered mesopores, and the aperture is 2.5-3.5 nm. The material is prepared by adopting a simple one-pot method, a silicon source and a carbon source are added into a mixed solution of ethanol / deionized water / ammonia water / hexadecyl trimethyl ammonium bromide, a proper amount of silicon source is added after reaction for a period of time, and an obtained solid product is dried and roasted to obtain the mesoporous silicon dioxide with the eggshell-yolk structure. The invention has the beneficial effects that the provided material is regular in structure and large in specific surface area, and has good application prospects in the fields of catalysis, adsorption separation, drug sustained release and the like.

Description

technical field [0001] The invention belongs to the field of material preparation, and in particular relates to an eggshell-egg yolk structured mesoporous silica material and a preparation method thereof. Background technique [0002] In recent years, mesoporous silica materials with special configurations (such as core-shell structure, hollow sphere structure, etc.) have attracted extensive attention from researchers. Compared with conventional mesoporous silica materials, these hierarchical structure materials often have larger specific surface area and structural functionality, and have broad application space in the fields of catalysis, adsorption and separation (Science, 1998, 282, 1302; Chem. Mater., 2009, 21, 4122; Chem. Commun., 2008, 2629.). [0003] In contrast, the core-shell structure often has more advantages in the design of functional materials than the hollow sphere structure. As a typical core-shell structure material, the "eggshell-egg yolk" structure (yo...

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Problems solved by technology

However, because of the particularity of the structure, the preparation of materials with the "eggshell-yolk" structure usually requires cumbersome steps and complicated processes

For example, Tan et al. synthesized organic-inorganic hybrid silica spheres with a "sandwich" structure, and then removed the organic components by etching to obtain a silica material with an "eggshell-yolk" structure (Adv.Mater., 2009,21,3804.), although its outer shell is a mesoporous structure, its inner core is a non-porous solid sphere, resulting in a smaller specific surface area of ​​the material, and the N-(2-aminoethyl)-3 used in its synthesis -Aminopropyltrimethoxysilane is expensive and not suitable for mass production

Zhang et al. (Angew.Chem.Int.Ed., 2008, 47, 5806.) used sodium borohydride solution to selectively etch colloidal silica spheres to obtain silica with "eggshell-yolk" structure , but the material has low porosity and small specific surface area, which limits its application

Therefore, it is still a challenge to develop a simple preparation process to synthesize silica with a more applicable "eggshell-yolk" structure.

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