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    Electrodeposition and characterization of as-deposited and annealed CdTe thin films.
    (Ceylon Journal of Science, 45(2), 53–59. DOI: http://doi.org/10.4038/cjs.v45i2.7388, 2016) Kumarasinghe, K. D. M. S. P. K.; De Silva, D. S. M.; Pathiratne, K. A. S.; Salim, H. I.; Abdul-Manaf, N. A.; Dharmadasa, I. M.
    Thin films of CdTe semiconductor materials were grown on fluorine doped tin oxide (FTO) conducting glass substrates using the technique of electrodeposition. CdSO4 at high concentrations and CdCl2, TeO2 at low concentrations were used as precursor salts for electrodeposition. The range of deposition potentials was estimated using cyclic voltammetric measurements. The electrical, optical, structural and morphological characteristics of as-deposited and annealed CdTe thin films were characterized using photo-electrochemical (PEC) cell studies, UV-Vis spectrophotometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). These particular samples were converted from n-type into p-type after heat treatment. UV-Vis spectrometric measurements for CdTe layers indicated that, the energy band gaps of 1.45±0.02 eV for both as-deposited and annealed samples which exhibited the required optical property for fabricating CdS/CdTe solar cells. Little increase in (220) and (311) peaks of XRD spectra were observed for annealed layers compared to the as-deposited material. However, annealing exhibited a small reduction of cubic phase preferential orientation (111). The optical transmission for both as-deposited and annealed CdTe samples were about 60% for wavelengths longer than about 850 nm.
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    Electrodeposited Cu2O homojunction solar cells: Fabrication of a cell of high short circuit photocurrent
    (Elsevier, 2016) Wijesundera, R.P.; Gunawardhana, L.K.A.D.D.S.; Siripala, W.
    A Cu2O homojunction solar cell was fabricated using a consecutive electrodeposition method of deposition of an n-Cu2O film followed by a p-Cu2O film, in two different acetate baths. Both n-type and p-type film growth conditions were optimized separately to yield high photocurrents in a photoelctrochemical (PEC) cell. Further, the resulted bi-layer films were investigated in the PEC for the verification of the formation of the p-n homojunction. In addition, p-Cu2O film surfaces of the bi-layers were sulphided using Na2S and (NH4)2S in order to improve the photoresponse of the homojunction before depositing a Au film for the solar cell device. The structural, morphological and optoelectronic properties of the Cu2O films were investigated using X-ray diffraction (XRD), scanning electron micrographs (SEMs), dark and light current–voltage (I-V) and spectral response measurements and observed that the films are of good quality. Incident photon to current efficiency (IPCE) and I-V characteristics of the solar cell device demonstrated that the Cu2O homojunction can produce a high short circuit current density Jsc. However, the overall conversion efficiency of the device is low due to poor fill factor and Voc. The solar cell characteristics of the structure Ti/n-Cu2O/p-Cu2O/Au were Voc=287.0±0.1 mV, Jsc=12.4±0. 1 mA/cm2, FF=25±2% and η=0.89±0.02%, under AM 1.5 illumination. The record high Jsc value of the device demonstrates the prospect being improved the efficiency of Cu2O homojunction solar cells by optimizing deposition, pretreatment and post treatment processes.
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    Spectral responses of electrodeposited cuprous oxide thin film electrodes
    (Journal of the National Science Council of Sri Lanka, 1995) Siripala W
    Photoresponse of the electrodeposited cuprous oxide thin film electrodes were investigated in a photoelectrochemical cell. Spectral response measurements reveal that a Schottky-type junction is formed at the junction between the substrate and cuprous oxide resulting in n-type and p-type photosignals in a photoelectrochemical cell. The electrodeposited cuprous oxide is an n-type semiconductor.