Rapid preparation of large-area graphene/metal composite structure SERS substrate method

Abstract

The invention discloses a method for quickly preparing a large-area graphene / metal composite structure surface enhanced Raman scattering substrate. Pulse laser is used to process a line array pattern on the surface of the substrate to form a plurality of laser processing areas and a plurality of laser non-processing areas which are distributed alternately, wherein a material removed from the laser processing areas is deposited in the laser non-processing areas in the form of nanoparticles; a metal film is deposited on the processed substrate to form a metal nano-structure; graphene is transferred to the surface of the metal nano-structure; a PMMA solution is added dropwise to completely cover graphene, and drying is performed, so that graphene adheres to the metal nano-structure closely; and finally the PMMA is removed and cleaning is performed, so that the graphene / metal composite structure surface enhanced Raman scattering substrate is obtained. The large-area graphene / metal composite structure surface enhanced Raman scattering (SERS) substrate can be prepared quickly and efficiently at a low cost, and the manufactured SERS substrate is high in sensitivity and good in consistency.

Description

technical field [0001] The invention belongs to the technical field of Raman detection, and in particular relates to a method for rapidly preparing a large-area graphene / metal composite structure surface-enhanced Raman scattering substrate. Background technique [0002] Raman spectroscopy is a scattering spectrum that contains material structure information. It is the light scattering caused by the inelastic collision between incident photons and molecular vibration and rotation quantized energy level resonance. It is an effective means of material identification. However, due to the weak Raman scattering intensity (usually less than 10 of the incident light -6 ), and the Raman scattering cross-section is much smaller than the fluorescence scattering cross-section, resulting in the weak Raman scattering signal is often lost in the fluorescence signal, which limits the application of Raman spectroscopy. Surface-enhanced Raman scattering (SERS) is an effective means to enhanc...

AI Technical Summary

Problems solved by technology

The surface morphology of rough metal electrodes prepared by electrochemical roughening is disordered, and the size and shape are not easy to control, resulting in poor consistency of SERS signals and cannot be used for quantitative measurement

The nanoparticle synthesis method has the disadvantages that the nanoparticles are easy to agglomerate and unstable, and the residual chemical impurities in the synthesis process make the SERS substrate have a large background signal, which cannot be used for the detection of trace substances.

Micro-nano etching methods mainly include photolithography, electron beam etching, and focused ion beam etching. Micro-nano etching can produce uniform arrays of micro-nano structures, but such methods are low in efficiency, high in cost, and The preparation process is cumbersome

(2) Problems existing in graphene self-assembly: the self-assembled graphene does not fully adhere to the metal substrate, resulting in an increase in the distance between the probe molecules adsorbed on the graphene surface and the metal substrate, and the Raman signal enhancement ability is weakened

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