One-Step Synthesis of Graphene, Copper and Zinc Oxide Graphene Hybrids via Arc Discharge: Experiments and Modeling

Aichata Kane,Aliou Hamady Barry,Ivaylo Hinkov,Ovidiu Brinza,Salim Mourad Cherif,Samir Farhat,Mongia Hosni

doi:10.3390/coatings10040308

Abstract

In this paper, we report on a modified arc process to synthetize graphene, copper and zinc oxide graphene hybrids. The anode was made of pure graphite or graphite mixed with metals or metal oxides. After applying a controlled direct current, plasma is created in the interelectrode region and the anode is consumed by eroding. Continuous and abundant flux of small carbon, zinc or copper species, issued from the anode at a relatively high temperature, flows through the plasma and condenses in the vicinity of a water-cooled cathode leading to few-layered graphene sheets and highly ordered carbon structures. When the graphite rod is filled with copper or zinc oxide nanoparticles, few layers of curved graphene films were anchored with spherical Cu and ZnO nanoparticles leading to a one-step process synthesis of graphene hybrids, which combine the synergetic properties of graphene along with nanostructured metals or semiconducting materials. The as-prepared samples were characterized by Raman spectroscopy, X-ray diffraction (XRD), spatially resolved electron energy loss spectroscopy (EELS), energy filtered elemental mapping and transmission electron microscopy (TEM). In addition to the experimental study, numerical simulations were performed to determine the velocity, temperature and chemical species distributions in the arc plasma under specific graphene synthesis conditions, thereby providing valuable insight into growth mechanisms.

Highlights

Transformation of two-dimensional one-atom-thick sheet of graphene (Gr) into three-dimensional architectures extends the outstanding properties of graphene [1] to novel graphene hybrid (GrH)materials such as graphene-semiconducting (GrSC) or graphene metals (GrM)
The reactor was cooled down to the ambient temperature and soot formed on the reactor walls was collected and sieved by a 60 micron stainless steel sieve in order to exclude any heavy particles as graphite or metal ejected from the anode by spallation in which fragments of graphite called “spalls” are expelled from the body of the anode and survive to the plasma [52]
We performed structural and molecular analysis by Raman spectroscopy complemented by detailed crystallographic study via X-ray diffraction (XRD)

Summary

Introduction

Materials such as graphene-semiconducting (GrSC) or graphene metals (GrM). Graphene exhibits impressive conjunction of mechanical, thermal, photoelectric and electronic properties such as excellent thermal conductivity (as high as 5000 W m−1 K−1 ) [2], high specific surface area To extend the field of graphene applications, new hybrids are proposed by combining graphene’s large surface area with carbon nanotubes, nanometric metals or Coatings 2020, 10, 308; doi:10.3390/coatings10040308 www.mdpi.com/journal/coatings. Coatings 2020, 10, 308 semiconducting metal oxides enhancing electron transfer kinetics within new 3D conducting networks. Synergy between axial properties of nanotubes [5], quantum confined metallic (M) or semiconducting (SC) nanoparticles [6] and graphene is the key issue in determining the performance of these hybrid nanostructures with great promise for applications. The matrix is composed of a metal as copper [7,8] and the graphene with low concentration from 0.5 wt

Methods

Results

Conclusion