Kuwait University, Kuwait
Title: Co-electrodeposition of Zn-rich Cu-Zn-Sn metallic alloy and its conversion to Cu2ZnSnS4 and Cu2ZnSnSe4 photovoltaic absorber films
Biography: Ali Rakhshani
Cu2ZnSnS4 (CZTS) and Cu2ZnSnSe4 (CZTSe) compound semiconductors are promising absorber materials for thin film solar cells due to their intrinsic p-type conductivity, high optical absorption coefficient, and suitable band gap energy. Furthermore, these absorber films are composed from the abundant and non toxic elements. Among different techniques which can be used for the preparation of these two absorber layers, solution processed techniques are very attractive due to their simplicity and low cost advantages. Here, we report the results of our study on the co-electrodeposition of a Zn-rich precursor metallic alloy Cu-Zn-Sn film from a single water-based solution with a composition not previously reported. The precursor films were converted to CZTS and CZTSe by vapor phase sulfurization and selenization processes. The synthesized films were characterized for their surface morphology and structure by using scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. Raman spectroscopy was employed for the identification of films and the detection of impurity phases which could exist. Photocurrent spectroscopy was used to measure the films optical transition energies, including the band gap energy. Heterojunction CdS/CZTS and CdS/CZTSe devices with the typical diode-type current-voltage characteristics could be prepared and their device parameters were evaluated. The results revealed that device-quality absorber films can be synthesized successfully by co-electrodeposition from a single bath solution used in this study.
Recent Publications :
- Rakhshani A E (2017) Charactrization and device applications of p-type ZnO films prepared by thermal oxidation of sputter-deposited zinc oxynitride, Journal of Alloys and Compounds 695: 124-132
- Rakhshani A E (2016) Solution-grown near-stoichiometry
Cu2ZnSnS4 films: Optical transitions and defect levels, Journal of
Alloys and Compounds 675: 387-392.
- Rakhshani A E, Thomas S (2015) Cu2ZnSnS4 films grown on flexible
substrates by dip coating using a methanol-based solution:
electronic properties and devices, Journal of Electronic Materials
4. Rakhshani A E (2014) Visible light emission and UV light detection
properties of solution-grown ZnO/polymer heterojunction diodes
on stainless steel foil, Applied Surface Science 311: 614 – 620.
5. Rakhshani A E, Thomas S (2013) Nitrogen doping of ZnTe for the
preparation of ZnTe/ZnO light emitting diode, J. Mater. Sci. 48:
6386 – 6392.