Electrodeposition of submicron/nanoscale Cu2O/Cu junctions in an ultrathin CuSO4 solution layer

The electrodeposition experiments were carried out in an ultrathin CuSO₄ solution layer under lower growth driving forces and the structure of electrodeposits were characterized by FESEM, chemical etching, EDS and DC conducting measurement. It was found that the Cu₂O crystallites distributed over the entire sample surface and formed submicron/nanoscale Cu₂O/Cu junctions. Meanwhile, the abnormal growth of Cu₂O crystallites in the electrodeposit front area was found for the first time. In the study, we present the obvious evidences for clarifying the relationship between the morphology and the compositional distribution of electrodeposits at grain size level. This result may be helpful for us to prepare the electrodeposits with controlled surface morphology at micro–nanoscale.