Photoelectrochemical solar cell studies on electroplated cuprous oxide thin films

Abstract

Cuprous oxide (Cu2O) is an interesting p-type semiconductor with a band gap of 2 eV suitable for solar cell applications. Deposition of Cu2O thin films by electrodeposition from aqueous solutions is a low temperature and inexpensive technique. in the present work, Cu2O thin films were cathodically deposited on Cu and tin oxide coated glass substrates by the cathodic reduction of copper (II) lactate solution. The optimized deposition conditions to synthesize cuprous oxide thin films were experimentally identified as; Deposition potential: −0.555 V versus SCE, pH: 9.0 ± 0.1, Bath temperature: 70∘C. X-ray diffraction studies revealed the formation of single phase cubic Cu2O films. The effect of annealing on the structure and morphology of Cu2O thin films are studied. The dielectric susceptibility, optical conductivity and packing density are evaluated. Photoelectrochemical solar cells based on p-Cu2O films are constructed. Spectral response studies indicate a peak in photo current density around 600 nm corresponding to the band gap of Cu2O thin films. The effects of annealing, chemical etching and photo etching on the solar cell parameters are studied.