Selective detection of methylene blue on the Ag2 W2 O7@ Au nanobelts by SERS

The pH value of the mixed solution of Na2WO4 ^2H2O and AgNO3 was adjusted by hydrothermal method, and ultra-thin Ag2W2O7 nanobelts were prepared. The Ag2W2O7 @ Au composite nanomaterial was prepared by ion beam sputtering. Using Ag2W2O7 @ Au as the active substrate for surface enhanced Raman scattering, it was used for the detection of six kinds of organic dyes including methylene blue ( MB) at low concentration. The experimental results showed that the surface enhanced Raman scattering effect (SERS) of MB dye molecules was enhanced significantly. The limit of detection (LOD) of MB was 82.8 pmol/L, and the enhancement factor was 1.08 x106. In addition, while a mixed solution of the above dye molecules with a concentration of 1.0 nmol/L was chosen as the probe molecule,it was found that only the characteristic Raman peak of MB can be detected on the Ag2W2O7@ Au substrate. The SERS test of 15 different test points on the same substrate with MB concentration of 10 nmol/L revealed that the relative standard deviations (RSDs) of the enhancement effect were all lower than 15%. This indicates that the Ag2W2O7@ Au substrate is an effective SERS active substrate for selective detection of MB molecules. © 2021, Youke Publishing Co.,Ltd. All rights reserved.