▎ 摘 要
Transferring CVD graphene using surfactant protected Au nanoparticles (Au NPs) avoids the use of PMMA and opens new ways of building heterojunctions for TERS and SERS applications. Thermal treatment removes organics from the Au NPs and leads to larger nanoparticles and the formation of networks, dimmers, and nanoplates of various shapes (circles, hexagons, and triangles). Raman and HRTEM revealed bilayer graphene and Moire patterns as determined by the 2D band and dislocated atomic layers, respectively. TERS performed on the heterojunction exhibits a reversible increase in frequency and sharpening of the characteristic bands in graphene along with the exaltation of bands such as D + D'. A close examination into a single triangular-shape nanoplate reveals that the most irregular area of the nanoplate is consistent with the higher Raman enhancement of Rh6G when compared to other areas of the same feature. This work may shed light onto new ways of transferring graphene, fundamental aspects concerning local strains in the heterojunction, and SERS on a single Au nanostructure.