Polydopamine-silver particle-polydopamine type surface-enhanced Raman spectroscopic substrate and preparation method thereof

Abstract

The invention discloses a polydopamine-silver particle-polydopamine type surface-enhanced Raman spectroscopic substrate. The surface of a substrate sheet is successively coated with a polydopamine layer, a nano-silver particle layer and another polydopamine layer from bottom to top. A preparation method for the substrate comprises the following steps: cleaning an adhesion substrate sheet; then growing polydopamine on the substrate sheet in virtue of a dopamine-Tris solution; carrying out ultrasonic cleaning so as to obtain the substrate sheet on which the smooth polydopamine layer is adhered; then allowing the nano-silver particle layer to be adhered onto the substrate sheet with the adhered smooth polydopamine layer; and carrying out growth of polydopamine in virtue of the dopamine-Tris solution again so as to obtain the substrate. The method provided by the invention is simple in experimental environment, does not produce an unwanted reducing agent, adopts dopamine in-situ reduction and discharges no toxic matters; the making period of the substrate is short, and enhanced effect value can reach 3.6*10<6>; and the substrate has stable performance and can be preserved for three months under simple preservation conditions.

Description

technical field [0001] The invention relates to a nanometer material, in particular to a polydopamine-silver particle-polydopamine surface-enhanced Raman spectrum substrate and a preparation method thereof. Background technique [0002] Indian physicist Raman irradiated benzene liquid with a mercury lamp in 1928 and discovered a new radiation spectrum line, that is, at the incident light frequency ω 0 Symmetrically distributed on both sides of , the frequency is ω 0 -omega and omega 0 The sharp sideband of +ω, which belongs to a new kind of molecular radiation, was later called Raman scattering, where ω is the elementary excitation frequency of the medium. Raman was awarded the 1930 Nobel Prize in Physics for his discovery of this new molecular radiation and for his many achievements in light scattering research. At the same time, the former Soviet Union Landsberger and Mandelstad reported that a similar phenomenon was found in quartz crystals, that is, Raman scattering c...

AI Technical Summary

Problems solved by technology

[0004] However, it is still a challenge to produce a substrate with certain universality when testing various DUTs in different environments, and because the SERS substrate has a metal surface, it will inevitably be exposed to the air. Oxidation, the strong timeliness of the substrate is its obvious characteristic

Therefore, the preservation of the SERS substrate is also a troublesome matter, which also determines that this technology is not easy to go out of the laboratory, and usually the substrate production process is cumbersome and requires high technical requirements, and there will be varying degrees of failure during the process. Toxic reducing agents or other toxic wastes are discharged, such as Shang Guangyun’s report on the preparation of red nano-silver colloid by hydrazine reduction and its spectral characteristics and Tang Jiaoping’s hydrazine hydrate reduction method to prepare silver nanoparticles. Hydrazine hydrate is used. This kind of highly toxic reducing agent is very polluting to the environment. In addition, it is difficult to preserve the general substrate for a long time. If you want to preserve it for a long time, the conditions will be very harsh, which will limit the promotion of this technology.

Images