阅读说明：本技术 一种具有中空球状结构的表面增强红外基底及其制备方法 (Surface-enhanced infrared substrate with hollow spherical structure and preparation method thereof ) 是由 田燕龙 王毅 王箫 高学军 龚蓉晔 王志文 杨海山 刘志国 于 2020-07-22 设计创作，主要内容包括：本发明公开了一种具有中空球状结构的表面增强红外基底及其制备方法,属于红外光谱技术领域。本发明的一种具有中空球状结构的表面增强红外基底的制备方法按照以下步骤进行：一、溅射金属材料；二、将金属材料/单层胶体晶体微球模板复合基底浸入到溶剂中去除胶体晶体模板或将金属材料/单层胶体晶体微球模板复合基底在高温下热处理去除胶体晶体模板。本发明制备得到的表面增强红外吸收光谱的增强基底,可实现从近红外到中红外的宽波段红外信号增强,进一步拓展了表面增强红外光谱技术的应用范围,以解决现有表面增强红外基底的性能不足的问题。(The invention discloses a surface-enhanced infrared substrate with a hollow spherical structure and a preparation method thereof, belonging to the technical field of infrared spectroscopy. The preparation method of the surface enhanced infrared substrate with the hollow spherical structure is carried out according to the following steps: firstly, sputtering a metal material; and secondly, immersing the metal material/single-layer colloidal crystal microsphere template composite substrate into a solvent to remove the colloidal crystal template or carrying out heat treatment on the metal material/single-layer colloidal crystal microsphere template composite substrate at high temperature to remove the colloidal crystal template. The enhanced substrate of the surface enhanced infrared absorption spectrum prepared by the invention can realize the enhancement of broadband infrared signals from near infrared to intermediate infrared, further expands the application range of the surface enhanced infrared spectrum technology and solves the problem of insufficient performance of the existing surface enhanced infrared substrate.)

1. A preparation method of a surface enhanced infrared substrate with a hollow spherical structure is characterized by comprising the following steps:

firstly, sputtering a metal material:

sputtering a metal layer on the substrate with the surface covered with the single-layer colloidal crystal microsphere template by using a magnetron sputtering method to obtain a metal material/single-layer colloidal crystal microsphere template composite substrate;

secondly, removing the single-layer colloid crystal microsphere template:

removing the single-layer colloid crystal microsphere template by adopting any one of the following two methods to obtain a hollow nanosphere substrate;

the method comprises the following steps: immersing the metal material/single-layer colloid crystal microsphere template composite substrate into a solvent for 10-600 min to obtain a surface enhanced infrared substrate with a hollow spherical structure;

the second method comprises the following steps: and (3) carrying out heat treatment on the metal material/single-layer colloid crystal microsphere template composite substrate at the temperature of 250-550 ℃ for 10-120 min to obtain the surface enhanced infrared substrate with the hollow spherical structure.

2. The method according to claim 1, wherein the operating parameters of the magnetron sputtering method in the first step are as follows: the deposition pressure (argon) is 0.5Pa to 3Pa, the sputtering power is 40W to 100W, and the sputtering time is 15min to 60 min.

3. The method according to claim 1, wherein the colloidal crystal microspheres in the first step are polystyrene microspheres or polymethyl methacrylate microspheres.

4. The method according to claim 1, wherein the substrate in the first step is a common glass, a quartz glass or a silicon wafer.

5. The method according to claim 1, wherein the metal material in the first step is one or a mixture of gold, silver and copper.

6. The method according to claim 1, wherein the diameter of the spheres in the surface-enhanced infrared substrate having a hollow spherical structure obtained in the second step is 50nm to 800 nm.

7. The preparation method according to claim 1, wherein the solvent in the second step is one or a mixture of toluene, tetrahydrofuran, dichloromethane and ethyl acetate.

8. The surface-enhanced infrared substrate having a hollow spherical structure prepared by the preparation method according to any one of claims 1 to 7.

Technical Field

The invention relates to a surface enhanced infrared substrate with a hollow spherical structure and a preparation method thereof, belonging to the technical field of infrared spectroscopy. The surface enhanced infrared absorption spectrum enhancement substrate can be used for enhancing broadband infrared signals from near infrared to intermediate infrared.

Background

In 1980, Harstein et al discovered the phenomenon of surface-enhanced infrared absorption for the first time when studying the adsorption of island-shaped Au and Ag films sputtered on Si substrates to nitrobenzoic acid molecules by using an attenuated total reflection method. When metal particles such as Au, Ag and the like are irradiated by infrared light, plasmas can be formed on the surfaces of the metal particles, and infrared absorption of absorption molecules can be enhanced when the metal particles are coupled with incident light. Today, surface-enhanced infrared spectroscopy has achieved many applications in surface catalysis, trace analysis, biochemistry, etc., but insufficient performance of surface-enhanced substrates remains a key issue limiting the large-scale application of surface-enhanced infrared spectroscopy.

The frequency and width of Localized Surface Plasmon Resonance (LSPR) are related to the size and shape of the metal particles, and the adjustment of the plasma resonance peak position can be realized by controlling the size, morphology and structure of the metal nanoparticles. The hollow nanospheres are a very good plasma material, and have plasma characteristics adjustable from the visible region to the near infrared region by adjusting the size of the spheres and the thickness of the shell.

The hard template method is a common method for preparing hollow nanospheres. Tanglinaong et al (CN101168597B) prepared a hollow polymer submicron sphere coated with a gold shell by a chemical adsorption method by using the polymer submicron sphere as a template. Wangshulin et al (CN100359030C) use colloidal crystal as template, and adopt the process of first impregnating and sensitizing, then chemically plating metal to prepare two-dimensional and three-dimensional ordered nano-structure metal material formed from hollow metal spheres. An ordered hollow gold nanosphere array was prepared by using a layer-by-layer self-assembly technique with polystyrene colloidal microspheres, by Zhijian Liang et al (Chemistry of materials,2003,15(16): 3176-. The research is to prepare the hollow nanospheres by a wet chemical method, the process is complex, the repeatability is low, and the application of the hollow nanospheres in the aspect of surface-enhanced infrared spectroscopy is not involved.

Disclosure of Invention

The invention provides a preparation method of a surface enhanced infrared substrate with a hollow spherical structure, which aims at solving the problem of insufficient performance of the existing surface enhanced infrared substrate, and the LSPR property of the surface enhanced infrared substrate is controllable.

In order to achieve the purpose, the invention adopts the following technical means:

the invention discloses a preparation method of a surface enhanced infrared substrate with a hollow spherical structure, which comprises the following steps:

firstly, sputtering a metal material:

sputtering a metal layer on the substrate with the surface covered with the single-layer colloidal crystal microsphere template by using a magnetron sputtering method to obtain a metal material/single-layer colloidal crystal microsphere template composite substrate;

secondly, removing the single-layer colloid crystal microsphere template:

removing the single-layer colloid crystal microsphere template by adopting any one of the following two methods to obtain a hollow nanosphere substrate;

the method comprises the following steps: immersing the metal material/single-layer colloid crystal microsphere template composite substrate into a solvent for 10-600 min to obtain a surface enhanced infrared substrate with a hollow spherical structure;

the second method comprises the following steps: and (3) carrying out heat treatment on the metal material/single-layer colloid crystal microsphere template composite substrate at the temperature of 250-550 ℃ for 10-120 min to obtain the surface enhanced infrared substrate with the hollow spherical structure.

Preferably, the working parameters of the magnetron sputtering method in the step one are as follows: the deposition pressure (argon) is 0.5Pa to 3Pa, the sputtering power is 40W to 100W, and the sputtering time is 15min to 60 min.

Preferably, the colloidal crystal microspheres in the first step are polystyrene microspheres or polymethyl methacrylate microspheres.

Preferably, the substrate in the first step is common glass, quartz glass or a silicon wafer.

Preferably, the metal material in the step one is one or a mixture of gold, silver and copper.

Wherein, the diameter of the sphere in the surface enhanced infrared substrate with the hollow spherical structure obtained in the second step is preferably 50nm to 800 nm.

Wherein, the solvent in the second step is preferably one or a mixture of several of toluene, tetrahydrofuran, dichloromethane and ethyl acetate.

The surface enhanced infrared substrate with the hollow spherical structure prepared by the preparation method of any one of the above is also within the protection scope of the invention.

Compared with the prior art, the invention has the beneficial effects that:

the surface-enhanced infrared substrate with the hollow spherical structure can realize accurate control of LSPR (localized surface plasmon resonance) properties by adjusting the size of the sphere and the thickness of the metal shell, can realize broadband infrared signal enhancement from near infrared to mid infrared when being used for surface-enhanced infrared spectrum application, and further expands the application range of the surface-enhanced infrared spectrum technology.

Drawings

FIG. 1 is an SEM image of a single-layer colloidal crystal template obtained in step one of example 1;

FIG. 2 is a graph showing the actual IR spectrum enhancement effect of the surface enhanced IR substrate having a hollow spherical structure obtained in step two of example 1;

FIG. 3 is an SEM image of a surface enhanced infrared substrate with a hollow sphere structure obtained in step two of example 2.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer and more fully describe the technical solutions in the embodiments of the present invention, it is obvious that the described embodiments are a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.