Highlighting the Dynamics of Graphene Protection toward the Oxidation of Copper under Operando Conditions

Research output: Contribution to journalArticle

Abstract

We performed spatially resolved near-ambient-pressure photoemission spectromicroscopy on graphene-coated copper in operando under oxidation conditions in an oxygen atmosphere (0.1 mbar). We investigated regions with bare copper and areas covered with mono- and bi-layer graphene flakes, in isobaric and isothermal experiments. The key method in this work is the combination of spatial and chemical resolution of the scanning photoemission microscope operating in a near-ambient-pressure environment, thus allowing us to overcome both the material and pressure gap typical of standard ultrahigh-vacuum X-ray photoelectron spectroscopy (XPS) and to observe in operando the protection mechanism of graphene toward copper oxidation. The ability to perform spatially resolved XPS and imaging at high pressure allows for the first time a unique characterization of the oxidation phenomenon by means of photoelectron spectromicroscopy, pushing the limits of this technique from fundamental studies to real materials under working conditions. Although bare Cu oxidizes naturally at room temperature, our results demonstrate that such a graphene coating acts as an effective barrier to prevent copper oxidation at high temperatures (over 300 °C), until oxygen intercalation beneath graphene starts from boundaries and defects. We also show that bilayer flakes can protect at even higher temperatures. The protected metallic substrate, therefore, does not suffer corrosion, preserving its metallic characteristic, making this coating appealing for any application in an aggressive atmospheric environment at high temperatures.

Details

Authors
  • Mattia Scardamaglia
  • Claudia Struzzi
  • Alexei Zakharov
  • Nicolas Reckinger
  • Patrick Zeller
  • Matteo Amati
  • Luca Gregoratti
Organisations
External organisations
  • University of Mons
  • Elettra Sincrotrone Trieste
  • University of Namur
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Corrosion Engineering

Keywords

  • ambient-pressure XPS, coating, corrosion, operando, spectromicroscopy
Original languageEnglish
Pages (from-to)29448-29457
JournalACS Applied Materials and Interfaces
Volume11
Issue number32
Publication statusPublished - 2019 Aug 14
Publication categoryResearch
Peer-reviewedYes