Electrochemical Deposition and Microstructure of Copper (I) Oxide Films

Cu sub 2 O films were grown on stainless steel disks by the cathodic reduction of copper(II) lactate solution. The applied potential and bath pH have strong effect on the composition and microstructure of Cu sub 2 O films. Pure Cu sub 2 O films can be made at bath pH=9 with applied potential between -0.35 and -0.55 V (vs. SCE) or at bath pH=12. The preferred orientation of the Cu sub 2 O films can be controlled by adjusting the bath pH and/or the applied potential. The crystallite shape of the Cu sub 2 O film is strongly related to the texture of Cu sub 2 O film. The crystallite shapes change from four-sided pyramids in (100) oriented film to truncated pyramids or three-sided pyramids in (111) oriented films. The grain size can be controlled simply by varying the bath pH and/or the applied potential.