▎ 摘　　要

We design a reusable graphene-ordered silver nanohole (GE-AgNHs) substrate. A uniform periodic nanopore array is etched on the silver film by surface plasmons (SPs) photolithography. Graphene is transferred to AgNHs by wet transfer method. Graphene not only provides a molecular adsorption platform, but also serves as a reference and calibration layer to improve surface-enhanced Raman reproducibility. When the silver film is exposed to the air, it is easily oxidized. The graphene covers the surface of the silver film to block the air, thereby slowing down the oxidation of the silver film. The substrate is characterized by optical microscopy, field emission scanning electron microscopy (SEM) and Raman spectroscopy. From the SEM characterization results, it can be seen that the silver nanopores are evenly distributed. Meanwhile, the electric field distribution (vertical bar E vertical bar) of different aperture bases is simulated by Finite-Difference Time-Domain (FDTD) simulation. The simulation results show that the electric field strength increases slightly with the decrease of the aperture. The maximum electric field strength .E-max approximate to 11 V . m(-1) is obtained at D=220 nm, and the enhancement factor is calculated to be similar to 1. 46X 10(-4). Many experiments were carried on. Firstly, we performed a Raman mapping test on the GE-AgNHs substrate. The results show that the RSD values of graphene D, G and 2D peaks are 18. 3% , 22. 1% and 19. 8% , respectively, with good uniformity. Secondly, Raman test and quantitative analysis are carried on using crystal violet (CV) solution at concentrations of 10(-)(8)similar to 10(-)(4) mol . L-1. The exponential fitting of the relative intensity k(k= I-@1(178)/ I-@(2D)) in the range of 10(-8)similar to 10(-4) mol . L-1, the fitting degree R-2 = 97. 7%; if the data of 10(-4) mol . L-1 is neglected, it performs a linear fit with a fit of 96. 8%. Finally, SERS repeatability is performed on the GE-AgNHs substrate with a concentration of 10(-12) mol . L-1 rhodamine 6G (R6G) solution as the probe molecule and sodium borohydride solution as the cleaning solution. It can be seen from the optical micrograph and the Raman spectrum that there is a small number of impurities on the GE before cleaning; after cleaning, a clean GE Raman signal is obtained. The Raman signal of R6G can be detected before and after cleaning, indicating that the substrate repeatability is good; the Raman intensity is maintained at 50% at 773 cm(-1).