CdSe/FTO thin film electrodes prepared by chemical bath, electrochemical and combined elecrochemical/chemical bath depositions: A comparative assessment of PEC characteristics
Date
2016-03-23
Authors
Abdulrahman, Nour
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Abstract
CdSe thin films have been deposited onto fluorine doped tin oxide (FTO/glass) substrates by three different techniques, electrochemical deposition (ECD), chemical bath deposition (CBD) and combined method based on electrochemical deposition (ECD) followed by chemical bath deposition (CBD). The films were comparatively characterized by a number of techniques including (photoluminescence spectra (PL), electronic absorption spectra, scanning electron microscopy (SEM) and X-ray diffraction (XRD)). Photo-electrochemical (PEC) characteristics of the electrodes including photo-current density-voltage (J-V) plots, conversion efficiency (ƞ) and fill factor (FF) were then studies. The PEC measurements indicate that all the CdSe films have n-type, and optical absorption measurements show that the prepared films have emission band with almost similar wavelength range (600-540 nm, 2.06 - 2.29 eV), while ECD shows some blue shift (580-520 nm) with higher band gap values (2.06 - 2.29 eV) to (2.132.38) eV. XRD results show that the three systems involved nano-sized CdSe particles with cubic type crystals. The new ECD/CBD-CdSe electrode exhibited higher photoelectrochemical conversion efficiency (ƞ% ̴ 4.40) than either ECD- or CBD-CdSe film electrodes.