Monolayered graphene oxide as a barrier on polycrystalline copper substrate against thermal oxidation for a long duration

This work aimed to describe an innovative and economical method for coating copper with Graphene Oxide (GO) via dip coating and a study of the resulting barrier properties against oxidation. The thickness GO was found as an optimized thin film in the nanometer (0.5 -0.7 nm) range. The kinetics of thermal oxidation at low temperature (160 degrees C) is followed by an original procedure based on Raman spectroscopy. This approach permitted an unambiguous identification of cuprous oxide (Cu2O) on micron size regions and probed the measurement of the thin oxidized layer down to the nm scale. The findings showed that a monolayer of GO does not substantially alter oxidation kinetics at short times (similar to 1 h). Furthermore, it was found that GO film exhibited highly improved thermal oxidation stabilities due to remarkable gas barrier property. It remained an excellent candidate for passivation barrier and resistance to oxidation of copper since GO film significantly reduced the further propagation of the Cu2O layer at a long timescale (days) under the barrier film.