This paper focused on the preparation of cuprous oxide thin films on flexible ITO substrates via electrochemical deposition in alkaline aqueous solution of sodium lactate and cupric sulphate.The vohammet-tic curves indicates two well-defined cathodic peaks at about-500 and about-800 mV (vs Ag/AgCl) due to the presence of cupric ions in the electrolyte

which were attributed to the formation of Cu and Cu

2

O on the substrate

respectively.The dependency of the cathodic potential on the growth temperature and the pH value of the electrolyte were investigated according to the cycle volt-ampere method.Lowering of the cathodic deposition potentials and increase in the deposition current are evident with the increase in temperature for both cathodic peaks.Both cathodic peaks were also shifted anemically with the decrease in pH value

accompanied with the increase in deposition current.As compared with that obtained in weak acidic aqueous solution

the tendency of anodic shift of these two cathodic peaks according to the decrease in pH value decreased obviously

which may stems from the fully ionization of lactate acid under alkaline circumstances and the excessive lactate acid as the ligand for both Cu (Ⅰ) and Cu (Ⅱ).The surface morphology and crystalline features of the deposited thin films were obtained by using the scanning electron microscope and X-ray diffraction methods

re-spectively.It was observed that the electro-deposition of Cu/CuzO nanocrystalline thin films on the flexible substrate is feasible in the deposition temperature and pH value range investigated in this work.And the surface morphology and crystalline features of the resultant deposits depends heavily on the cathodic potentials when the deposition temperature and pH value are the same.