Greatly Enhanced Anticorrosion of Cu by Commensurate Graphene Coating

Abstract

Metal corrosion is a long-lasting problem in history and ultrahigh anticorrosion is one ultimate pursuit in the metal-related industry. Graphene, in principle, can be a revolutionary material for anticorrosion due to its excellent impermeability to any molecule or ion (except for protons). However, in real applications, it is found that the metallic graphene forms an electrochemical circuit with the protected metals to accelerate the corrosion once the corrosive fluids leaks into the interface. Therefore, whether graphene can be used as an excellent anticorrosion material is under intense debate now. Here, graphene-coated Cu is employed to investigate the facet-dependent anticorrosion of metals. It is demonstrated that as-grown graphene can protect Cu(111) surface from oxidation in humid air lasting for more than 2.5 years, in sharp contrast with the accelerated oxidation of graphene-coated Cu(100) surface. Further atomic-scale characterization and ab initio calculations reveal that the strong interfacial coupling of the commensurate graphene/Cu(111) prevents H O diffusion into the graphene/Cu(111) interface, but the one-dimensional wrinkles formed in the incommensurate graphene on Cu(100) can facilitate the H O diffusion at the interface. This study resolves the contradiction on the anticorrosion capacity of graphene and opens a new opportunity for ultrahigh metal anticorrosion through commensurate graphene coating.

Large Single‐Crystal Cu Foils with High‐Index Facets by Strain‐Engineered Anomalous Grain Growth

“…After the oxidation of the as‐obtained Cu foils at 180 °C for 2–5 min, the boundaries between polycrystalline regions and single crystalline regions can be clearly visible by naked eyes, because of their different oxidation rates (Figure 1b; and Figure S2, Supporting Information). [ 19 ]…”

Anisotropic Strain Relaxation of Graphene by Corrugation on Copper Crystal Surfaces

“…Graphene is impermeable to any molecules and has the potential as a perfect anticorrosion barrier. However, whether graphene can protect the underlying Cu substrates against oxidation is still under debate . The as‐grown graphene on Cu was stored in air for 1 week, and then characterized about the surface oxidation using SEM and Auger electron spectroscopy (AES).…”

Corrosion Behavior of Zinc–Nickel and Graphene Layered Structures on Steel Substrates

“…Defect sites in the assembled graphene layers can form hydrophilic gates that allow the diffusion of water molecules, oxygen, and salt ions. The defects can induce or accelerate corrosion . The pore size, that is, required for the water and ion transport is in the sub‐nanometer range according to computer simulation studies of desalination membranes .…”