Effect of Deposition Time on the Electrodeposited n-Cu₂O Thin Film

Abstract

This work demonstrates the fabrication of Cu2O thin film onto a fluorine-doped tin oxide (FTO) glass substrate via electrodeposition method which was conducted in a solution containing copper (II) acetate monohydrate and lactic acid. While varying the deposition time ranging up to 80 minutes, the solution was kept constant at solution temperature of 40°C, solution pH 6.5 and current density-0.3 mA/cm2. The characteristics of electrodeposited Cu2O were investigated via x-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), current-voltage (I-V) test and surface profiler. The XRD results showed the intensity peak of Cu2O corresponded to reflection (111) increased when the deposition time increased. The topological characteristics from AFM characterization showed the increment of surface roughness decreased as the time increased from 5 to 60 minutes. However, the surface roughness decreased when the time reached 70 and 80 minutes. I-V characteristics of all electrodeposited Cu2O showed Ohmic behaviours indicating the successful fabrication of n-Cu2O thin film. From this study, the significant effect of deposition time of Cu2O was clearly observed and plays an important role in providing mechanism growth of the film.

Optimization of Cu2O Thickness to Enhance Photocatalytic Properties of Electrodeposited Cu2O/FTO Photoanode

“…Next, AFM scanning was performed horizontally, and a "step height" profile was obtained, shown in Figure 3. In addition to better density and coverage of Cu2O grains on the FTO surface, the thickness of the Cu2O film increased from 370 to 1100 nm with the increasing deposition time [18,28]. This result was consistent with the increase in total charge during electrochemical deposition.…”

“…The number of Cu2O material on the FTO surface depended on the deposition times, where the total charge (electric current times deposition time) during the electrochemical deposition process determined the grain number. Hence, the number of Cu2O grains increased as the deposition time increased, leading to the increase of the Cu2O film thickness [18].…”

“…For example, the fabrication of Cu2O photoelectrode prepared at pH 6.2 exhibited n-type conductivity, while those obtained at pH 11 showed p-type conductivity [17]. Furthermore, the variation of deposition time can change the morphology and thickness of n-type Cu2O [18]. Several works have attempted to enhance the photocatalytic performance of n-type Cu2O by changing the deposition parameters in the electrochemical deposition method [10][11][12]19].…”

Optical and dielectric properties of electrochemically deposited p-Cu2O films

“…They found that the films are comprised of Cu 2 O nanoparticles with distinctive wavelike surface feature. Hanif [19] reported that deposition time affected the structural, morphological and topological properties of n-Cu 2 O thin films. From the above literature reviews, most of the works have reported on effect of deposition times on surface morphology, crystal quality properties of the Cu 2 O films.…”

Cu2O Heterojunction Solar Cell with Photovoltaic Properties Enhanced by a Ti Buffer Layer

“…Compared to other techniques, electrodeposition by dissolving the precursor of copper ions in deionized water for controlled deposition of the Cu 2 O thin films is versatile, environmental benign, cost-effective, operated at room temperature, and flexible for depositing on both rigid and flexible conducting substrates of a large area. The keys to control the growth, texture, grain size and shape, film thickness and surface morphology [29][30][31][32] in electrodeposition are by adjusting process parameters such as current density and voltage between the electrodes, deposition temperature and time, the composition of the electrolytic solution, etc. Solar cells fabricated by employing the electrodeposition of Cu 2 O films have been reported on Cu 2 O/ZnO/ITO, glass/Cr/ITO/Cu 2 O/Zn 1−x Mg x O/AZO, FTO/Cu 2 O/AZO, etc.…”