Abstract: Cuprous oxide (Cu₂O) thin films have been grown by electrodeposition technique onto ITO-coated glass substrates from aqueous copper acetate solutions with addition of sodium thiosulfate at 60℃. The effects of sodium thiosulfate on the electrochemical deposition of Cu₂O films were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were obtained at -0.58 V vs. SCE and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and optical, photoelectrochemical and electrical measurements. X-ray diffraction results indicated that the synthesized Cu₂O films had a pure cubic phase with a marked preferential orientation peak along (200) plane and with lattice constants a=b=c=0.425 nm. FTIR results confirmed the presence of Cu₂O films at peak 634 cm^-1. SEM images of Cu₂O films showed a better compactness and spherical-shaped composition. Optical properties of Cu₂O films reveal a high optical transmission (>80%) and high absorption coefficient (α > 104 cm^-1) in visiblelight region. The optical energy band gap was found to be 2.103 eV. Photoelectrochemical measurements indicated that Cu₂O films had n-type semiconductor conduction, which confirmed by Hall Effect measurements. Electrical properties of Cu₂O films showed a low electrical resistivity of 61.30 Ω·cm^-1, carrier concentration of -4.94×10¹⁵ cm^-3 and mobility of 20.61 cm²·V^-1·s^-1. The obtained Cu₂O thin films with suitable properties are promising semiconductor material for fabrication of photovoltaic solar cells.

Key words: Electrodeposition, Cuprous oxide, Thin films, Semiconductor, Cyclic voltammetry, Photoelectrochemical measurements

摘要： Cuprous oxide (Cu₂O) thin films have been grown by electrodeposition technique onto ITO-coated glass substrates from aqueous copper acetate solutions with addition of sodium thiosulfate at 60℃. The effects of sodium thiosulfate on the electrochemical deposition of Cu₂O films were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were obtained at -0.58 V vs. SCE and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and optical, photoelectrochemical and electrical measurements. X-ray diffraction results indicated that the synthesized Cu₂O films had a pure cubic phase with a marked preferential orientation peak along (200) plane and with lattice constants a=b=c=0.425 nm. FTIR results confirmed the presence of Cu₂O films at peak 634 cm^-1. SEM images of Cu₂O films showed a better compactness and spherical-shaped composition. Optical properties of Cu₂O films reveal a high optical transmission (>80%) and high absorption coefficient (α > 104 cm^-1) in visiblelight region. The optical energy band gap was found to be 2.103 eV. Photoelectrochemical measurements indicated that Cu₂O films had n-type semiconductor conduction, which confirmed by Hall Effect measurements. Electrical properties of Cu₂O films showed a low electrical resistivity of 61.30 Ω·cm^-1, carrier concentration of -4.94×10¹⁵ cm^-3 and mobility of 20.61 cm²·V^-1·s^-1. The obtained Cu₂O thin films with suitable properties are promising semiconductor material for fabrication of photovoltaic solar cells.

关键词: Electrodeposition, Cuprous oxide, Thin films, Semiconductor, Cyclic voltammetry, Photoelectrochemical measurements