Preparation method of nano-silver inverse opal SERS (Surface Enhanced Raman Scattering) probe for bipyridine herbicide detection

Abstract

The invention relates to a preparation method of a nano-silver inverse opal SERS (Surface Enhanced Raman Scattering) probe for bipyridine herbicide detection. The preparation method comprises the following steps: preparing a titanium dioxide inverse opal structure and preparing a silver nanoparticle-modified titanium dioxide inverse opal structure. The preparation process comprises two steps: firstly, taking PS microspheres as a template, forming a hexagonal close-packed colloidal crystal template through a gravity settling method, then filling gaps of the template with a titanium source solution, and carrying out aging and heat treatment to prepare a titanium dioxide inverse opal film, wherein the surface of the film is rich in hydroxyl, so that silver-ammonia ions are adsorbed on the surface of the film; reducing a silver-ammonia solution is into silver nanoparticles under the dual effects of stabilization and reduction of PVP, adhering paraquat and diquat molecules to the surface of nano-silver inverse opal under the electrostatic interaction, and enhancing conventional Raman signals of dipyridyl herbicide molecules by utilizing a local surface plasmon resonance field on the metal surface, wherein the detection limit is 10<-8> mol.L<-1>. The SERS probe prepared by the method is good in stability, good in selectivity and high in SERS responsivity.

Description

technical field [0001] The invention relates to the field of material science, in particular to a preparation method of a nano-silver inverse opal SERS probe capable of detecting trace amounts of bipyridine herbicides. Background technique [0002] Diquat and paraquat, bipyridyl herbicides, have broad-spectrum and high-efficiency characteristics, and are widely used in agricultural production. Diquat (DQ) and Paraquat (Paraquat, PQ) are contact-killing fast-acting herbicides with the same mode of action and weeding mechanism. Due to their strong water solubility, large usage and moderate toxicity, etc. The reason is that when it is applied to farmland, it may cause water pollution after being washed by rainwater into the water body, thereby endangering fish, algae and other aquatic organisms in the water body; direct contact will cause skin irritation, sensitization, and even ulcers; a large amount Ingestion and bioaccumulation can cause toxicity to the lungs, heart, liver,...

AI Technical Summary

Problems solved by technology

Significant spectral "contamination" can often be observed in complex sample matrices due to the often low concentration of target molecules and the matrix having the same pathway into the hot spot, leading to difficult analytical results

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