CVD Graphene Transferred with Au Nanoparticles: An Ideal Platform for TERS and SERS on a Single Triangular Nanoplate

PÉREZ, LUIS A.; DALFOVO, MARÍA C.; TROIANI, HORACIO; SOLDATI, ANALIA L.; LACCONI, GABRIELA; IBAÑEZ, FRANCISCO

JOURNAL OF PHYSICAL CHEMISTRY C

AMER CHEMICAL SOC

Lugar: Washington; Año: 2016 vol. 120 p. 8315 - 8322

1932-7447

Transferring CVD graphene using surfactantprotected 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 theformation of networks, dimmers, and nanoplates of various shapes (circles, hexagons, and triangles). Raman and HRTEM revealed bilayer graphene and Moirépatterns as determined bythe 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.