First principles study of oxidation resistance of atomically flat Cu(111) surface

Copper is one of the important materials used in modern technology and industries, but oxidation of copper deteriorates its application in nanotechnology. Our recent first principles total-energy calculations based on density functional theory is used to investigate the oxidation resistance of atomically flat Cu(111) surface. The exchange-correlation energy is described by the generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof (PBE) and projected augmented wave (PAW) method is employed. Our results show that atomically flat Cu(111) without multi-atomic steps is oxidation resistant. The energy barrier for oxygen penetrating flat surface and mono-atomic step is very high in comparison to multi-atomic steps. Also, incremental oxygen adsorption energy for the fcc site of the flat surface becomes positive and oxygen resistant above the oxygen coverage of 50%. These calculated results are consistent with the recent experimental finding.