Large-scale cathodic carboxylation of copper surfaces

Abstract

Large scale carboxylation of copper can easily be achieved by reduction of CO2 solubilised in aprotic polar solvents in the presence of tetramethylammonium salts (TMeA+X−). Carbon dioxide could be inserted into the metal matrix (presumably in the form of the carbon dioxide anion radical) at high surface concentrations (up to 10−7molcm−2), most probably organized in multi-layers. With significant amounts of electricity (>0.1×10−2Ccm−2), this cathodic procedure leads to an impressive corrosion phenomenon. Importantly, the interfacial carboxylation of copper may efficiently protect the interface against anodic corrosion (gain up to ΔE≈+1.3V). Moreover, the insertion process is reversible and anodic oxidation leads to release of gaseous CO2. Lastly, the external poly-carboxylated layers can easily be tailored to produce a variety of chemically modified interfaces.