Preparation method and application of ordered silver nanoparticle-bismuth nanosheet-copper mesh array

The invention relates to a preparation method and application of an ordered silver nanoparticle, bismuth nanosheet and copper mesh array, the preparation method comprises the following steps: carrying out an etching reaction on the surface of a copper mesh through an impregnation method to grow a bismuth nanosheet on the surface of the copper mesh, and sputtering silver nanoparticles to the surface of the bismuth nanosheet to obtain an ordered silver nanoparticle, bismuth nanosheet and copper mesh array film. Then, the array film is soaked in a 4-p-aminobenzaldehyde (4-ABZ) solution, and 4-ABZ molecules are adsorbed on the surface of the silver nanoparticle, bismuth nanosheet and copper net array to serve as signal probe molecules; then the silver nanoparticles, bismuth nanosheets and copper net arrays adsorbing the 4-ABZ molecules serve as a substrate to be placed in a packaging environment containing seafood, meat and other meat-derived food, the SERS signal intensity of the 4-ABZ molecules on the surface o