An-Najah Staff

Polycrystalline CdSe films have been deposited onto fluorine doped tin oxide (FTO/glass)
substrates by three different techniques, electrochemical deposition (ECD), chemical bath
deposition (CBD) and, for the first time, combined ECD and CBD (ECD/CBD). The films were
comparatively characterized by photoluminescence spectra (PL), electronic absorption spectra,
scanning electron microscopy (SEM) and X-ray diffraction (XRD).  The SEM micrographs show
that the films involved rod shaped agglomerates with various lengths and widths. XRD patterns
show that the three systems involved nano-sized CdSe particles with cubic type crystals. Based
on Scherrer’s equation, the ECD film showed larger particle size than the CBD film, while the
ECD/CBD film showed largest particles among the series.  Similarly, the band gap values varied
for different films as CBD > ECD > ECD/CBD. Photo-electrochemical (PEC) characteristics,
including photo-current density vs. voltage (J-V) plots, conversion efficiency (ƞ), fill factor (FF)
and stability were all studied for different film electrodes. The films exhibited n-type behaviors
with direct band gaps. The new ECD/CBD-CdSe electrode exhibited higher conversion
efficiency (ƞ%   4.40) than other counterparts. The results show the added value of combining
ECD and CBD methods in enhancing PEC characteristics of CdSe film electrodes, even with no
additional treatment.