Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface

Rebeca Ortega-Amaya,Mauricio Ortega-López,Andrés M Espinoza-Rivas,Yasuhiro Matsumoto,Manuel A Pérez-Guzmán

doi:10.3762/bjnano.7.93

Abstract

This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure.

Highlights

In the last years, graphene oxide (GO) and reduced graphene oxide have emerged as suitable candidates to prepare graphene-based nanocomposites [1,2], including those based on GO/inorganic nanoparticles [3]
In our previous work we assumed that they developed following a mechanism similar to that proposed by Glover and co-workers [21]. They demonstrated that Cu nanoparticles (CuNPs) can be formed on the surface of copper objects exposed to ambient humidity for a few minutes
We describe the formation of faceted core–shell Cu2O-reduced graphene oxide (rGO) and Cu-rGO nanoparticles on the surface of a Cu foil by annealing foil-supported graphene oxide (GO) under an Ar atmosphere

Summary

Introduction

Graphene oxide (GO) and reduced graphene oxide (rGO) have emerged as suitable candidates to prepare graphene-based nanocomposites [1,2], including those based on GO/inorganic nanoparticles [3]. They develop a highly faceted morphology and are coated with rGO sheets. The rGO-coated Cu-based nanoparticles developed at temperatures in the range of 200–1000 °C starting from bare Cu2O nanocrystals that formed at 80 °C.

Results

Conclusion