Preparation method and application of graphene oxide-gold nano-rod composite nano-material

Abstract

The invention provides a preparation method and an application of a graphene oxide-gold nano-rod composite nano-material. The method comprises the following steps: 1, sequentially adding silver ions, ascorbic acid (VC) and an auric chloride acid solution to synthesize gold nano-rods with colloidal gold nanoparticles as nucleation sites; 2, selecting a monolayer graphene oxide solution, further processing by using NaOH and sodium monochloroacetate, neutralizing an alkali residual after a reaction by using diluted hydrochloric acid, and modifying by an active carboxyl group to prepare sulfhydrylated graphene oxide (GO-SH); and 3, taking the gold nano-rods (GNRs) prepared in step 1 and the GO-SH prepared in step 2, stirring for full mixing, standing, centrifuging, and dispersing the obtained material in deionized water. The method has the advantages of simplicity, strong operationality and good reappearance, and the prepared nano-material has very good mono-dispersion and stability in an aqueous solution, and provides powerful safeguard for application in biological detection, sensing and chemical analysis.

Description

technical field [0001] The invention relates to a preparation method of a graphene oxide-gold nanorod composite nanomaterial, in particular to a preparation technology of a GO-GNR composite nanomaterial with Raman enhancement performance. Background technique [0002] The so-called surface Raman enhanced (SERS) effect mainly refers to the special preparation of some metals (mainly gold, silver and copper) or semiconductor surface (cadmium sulfide, titanium oxide) or sol, in the excited region, due to the sample surface or The enhancement of the electromagnetic field near the surface leads to the phenomenon that the Raman scattering signal of adsorbed molecules is several orders of magnitude stronger than the normal Raman scattering (NRS) signal. As early as 1974, Fleischman et al. first discovered the phenomenon of Raman scattering signal enhancement of pyridine molecules adsorbed on the surface of silver electrodes, and mistakenly believed that it was caused by a large incr...

AI Technical Summary

Problems solved by technology

At present, there are many methods for preparing SERS substrates, mainly including: gold and silver colloids prepared by chemical solution method; this method is simple and fast, does not require large-scale equipment, and also has some unavoidable shortcomings, such as: adding a large amount of surface activity during the synthesis process Covering the surface of nanoparticles affects the adsorption of probe molecules and even interferes with SERS detection; nanoparticles are easy to agglomerate, but the aggregation state is difficult to control, which will inevitably affect the stability and repeatability of SERS detection, and it is difficult to achieve controllability better synthesis etc.

There are physical etching methods (such as plasma etching, electron beam etching, photolithography, etc.), self-assembly methods (such as LB film method) and physical and chemical vapor deposition methods for the direct preparation of SERS on solid substrates. The SERS substrate prepared by this method has good particle uniformity and uniform and controllable physical and chemical properties, but all require large-scale instruments, high technical requirements, and are not easy to operate. It is difficult to achieve complex and irregular interfaces that cannot be done on a single molecule. testing requirements

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