Paper EM-TuP14
Hybridization and Characterization of Reduced Graphene Oxide with Copper Nanoparticles

Tuesday, October 20, 2015, 6:30 pm, Room Hall 3

An in-situ crystallization technique was used to prepare a hybrid containing Cu nanoparticles (NPs) bound to reduced graphene oxide (rGO) sheets. The hybrid material was investigated with scanning electron microscopy (SEM), Raman spectroscopy, ultraviolet visible spectroscopy (UV/vis), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). SEM results show that spherical Cu nanoparticles ranging from 1.6 to 7.4 nm in diameter and agglomerates were randomly dispersed on rGO sheets. SEM images show that Cu NPs were intercalated between rGO sheets to form a hybrid material. UV/vis of the rGO:Cu hybrid contained peaks associated with GO and Cu NPs with a blue shift in the peak resulting from n→pi^* transitions of C=O bonds to 283 nm and a red shift in the peak indicative of the Cu surface plasmon resonance to 585 to 630 nm. XPS confirmed the presence of CuO and Cu(OH)₂ with peaks at 933.4 and 934.5 eV respectively. The presence of imidazole, from the ionic liquid [Bmim][BF₄] used to synthesize the Cu NPs, was confirmed by the XPS peak found at 400.4 eV and the contributions to fingerprint regions in the FTIR. The as synthesized rGO:Cu hybrid had an electrical conductivity of 3.5*10⁶ S/m. This value is intermediate between GO with a baseline of 0.04 S/m and Cu NP thin film conductivity of 2.0*10⁷ S/m.