Title: Effect of alloying with Ruthenium on the properties of FeX2 (X=S, Se) thin films

Abstract

This research is interested in the fabrication of low-cost materials for several applications such as low-cost solar cells and several chemical applications. We focused on the Pyrite (FeS2, FeSe2,…etc) films because they are promising candidates for absorption and photocatalysis. Indeed, they are of great interest in applications of renewable energy conversion due to their high optical absorption coefficient (α>105 cm-1 for hν>1.4eV), their high abundance, their low cost, and their non-toxic constituent elements. Furthermore, the used technique for the fabrication of our pyrite layers is easier than others used previously, and it’s environmentally safe: it consists of spraying an aqueous solution of FeCl3.6H2O on pre-heated glass substrates followed by their heat treatment under sulfur or selenium atmosphere. However, after fabrication, the band gap energy values of the obtained pyrite films are close to 1eV that are shown relatively low for solar cells application. Thus, to develop pyrite-based photovoltaic, searching for practical ways to enlarge the band gap of FeS2 and FeSe2 is greatly necessary in the aim to achieve the optimum band gap energy value, for single-junction photovoltaic applications, within Shockley- Queasier theory, of about 1.5 eV. Alloying with ruthenium was our successful used technique. The fabricated Ru-alloyed pyrite films presented desired band gap energy values for several applications, especially for photovoltaic ones.

Biography

Beya Ouertani obtained her Bachelor's Degrees in physical sciences, her DEA in quantum physics, her PhD and the university qualification (“Habilitation”) about thin films for low cost solar cells, at the Faculty of Sciences of Tunis, University of Tunis El Manar. She had been researcher at the Photovoltaic and Semiconductor Materials Laboratory, at the National Engineering School of Tunis, University of Tunis El Manar, Tunisia. Then, she had attended the Laboratory of Semiconductors, Nanostructures and Advanced Technology (LSNTA), Research and Technology Center of Energy (CRTEn). During the last years she has been a researcher at the Photovoltaic Laboratory (LPV) at the same Research and Technology Center of Energy (CRTEn), Science and Technology Park of Borj Cedria, Tunisia. She has been teaching at the Higher Institute of the Environmental Sciences and Technologies of Borj Cédria, University of Carthage, since 2005.