Optik 135 (2017) 227–237 Contents lists available at ScienceDirect Optik journal homepage: www.elsevier.de/ijleo Original research article Electro-optical characterization of ruthenium-based dye sensitized solar cells: A study of light soaking, ageing and temperature effects Antonino Parisi ∗ , Riccardo Pernice, Andrea Andò, Alfonso C. Cino, Vincenzo Franzitta, Alessandro C. Busacca Department of Energy, Information Engineering and Mathematical Models (DEIM), University of Palermo, Viale delle Scienze, Building 9, 90128 Palermo, Italy a r t i c l e i n f o Article history: Received 8 November 2016 Accepted 29 January 2017 Keywords: Photovoltaics Dye sensitized solar cells (DSSCs) Light soaking Electro-optical characterizations a b s t r a c t In this work, we report on the electro-optical characterization of Dye Sensitized Solar Cells (DSSCs) which use ruthenium complexes as sensitizers. In particular, several kinds of mea- surements have been performed to study the electrical performances and the efficiency levels of the cells at different operating conditions. In detail, the measurements have been conducted at varying temperatures and hours of light soaking. Our results show that the short circuit current density J SC , the open circuit voltage V OC and the conversion efficiency  increase with the hours of light soaking, while they decrease with temperature. A thorough investigation on the light soaking process at the device level has been carried out, giving a wealth of experimental data which can be very useful to better single out and quantify the underlying physical phenomena and the effects on the cell parameters, which are still controversial among the scientific community. Finally, the ageing study demonstrates that the cell performance rapidly deteriorates in the first few months of exposure to light. All the obtained results are of great importance for a better understanding of the light soaking phenomenon and for improving the fabrication process of the DSSCs investigated during this study. © 2017 Elsevier GmbH. All rights reserved. 1. Introduction Starting with a glimpse of basic facts, we are assisting to a continuous and conspicuous increase of the world power consumption. Therefore, it is obvious that fossil fuel – which is nowadays the most commonly employed energy fuel – will soon need to be progressively more and more supported by the use of renewable energy sources (e.g., photovoltaics, wind power). In addition, another noteworthy disadvantage of fossil fuels consists in the fact that they contribute to increment the global warming. For the above-mentioned reasons, one of the most relevant research fields is to investigate on the utilization of sustainable carbon-free sources of energy. Among them, photovoltaics is definitely the most exploited one, since the Sun offers a huge amount of free and clean energy. Solar cells are devices that allow to directly convert the sunlight into electrical power, exploiting the photovoltaic effect discovered by Becquerel in 1839. ∗ Corresponding author. E-mail address: antonino.parisi@unipa.it (A. Parisi). http://dx.doi.org/10.1016/j.ijleo.2017.01.100 0030-4026/© 2017 Elsevier GmbH. All rights reserved.