Detection of hydrogen in corrosion of copper in pure water

Copper is generally assumed to be immune to corrosion by water itself. However, this is not supported by any scientific experimental evidence. Corrosion results from 15 years of exposure are presented here. A transition from O 2-consuming to H 2-evolving copper corrosion is concluded, which implies that copper can corrode by water itself. The complex corrosion product contains hydrogen. We have also measured a hydrogen uptake in the copper metal as a result of metallic copper corrosion by water which implies a sample thickness dependence on hydrogen uptake. The results are described in terms of autoionisation of water which offers an explanation why copper corrosion can take place in pure O 2-free water.