title: Thin and transparent films of graphene/silver nanoparticles obtained at liquid-liquid interfaces: preparation, characterization and application as SERS substrates.
abstract: We report here the synthesis and characterization of transparent and homogeneous thin films of reduced graphene oxide/silver nanoparticles (rGO/AgNPs) nanocomposites, starting from graphene oxide (GO) or reduced graphene oxide (rGO), directly obtained at a water/toluene liquid-liquid interface. Different films (obtained by varying the Ag/rGO or Ag/GO ratio) were prepared, deposited over glass or plastic substrates, and characterized by X-ray diffraction, UV-Vis and Raman spectroscopy, thermal analysis, transmission and scanning electron microscopy. Samples were evaluated as substrates for surface-enhanced Raman spectroscopy (SERS), using dilute solutions (1×10(-7) mol L(-1)) of a common probe molecule, 4-aminothiophenol (4-ATP). These materials exhibit significant high-quality SERS activity, and enhanced modes could be observed for 4-ATP, which suggested that charge transfer occurred between the Ag nanoparticles and 4-ATP molecules.
authors.affiliation: Departamento de Química, Universidade Federal do Paraná (UFPR), Curitiba, PR, Brazil.
authors.forename: Hiany
authors.initials: H
authors.lastname: Mehl
authors.affiliation: Departamento Acadêmico de Química e Biologia, Universidade Tecnológica Federal do Paraná (UTFPR), Curitiba, PR, Brazil.
authors.forename: Marcela Mohallem
authors.initials: MM
authors.lastname: Oliveira
authors.affiliation: Departamento Acadêmico de Química e Biologia, Universidade Tecnológica Federal do Paraná (UTFPR), Curitiba, PR, Brazil. Electronic address: aldozarbin@ufpr.br.
authors.forename: Aldo José Gorgatti
authors.initials: AJG
authors.lastname: Zarbin
keywords: Graphene; Liquid–liquid interfaces; Nanocomposites; SERS substrates; Silver nanoparticles