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In this work, we report on the modelling of light soaking effect on Ruthenium-based Dye Sensitized Solar cells (DSSCs). Such a phenomenon can be detected when exposing the cells at increasing hours of illumination and produces a reversible performance increase. Starting from the results obtained through the electro-optical characterization of the cells, we applied a one-diode circuital-model. Our results show a good agreement between the experimental and the simulated data, with a mean square error in the order of 10 −12 and a maximum error in current lower than 0.6%. Finally such results allowed us to infer some precise trends followed by the cells main electrical parameters and of their equivalent one-diode electrical model due to light soaking effect. [ABSTRACT FROM AUTHOR]

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 measurements 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 η 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. [ABSTRACT FROM AUTHOR]

Two new Ru(II) complexes bearing with substituted dipyrrinato ligands ( GS3 and GS10 ) have been successfully synthesized and characterized. These sensitizers exhibit panchromatic light harvesting properties, rendering them promising for DSSC applications. GS3 has shown high overall power conversion efficiency (η = 2.79%) compared to GS10 which is the highest so far in the case of Ru (II) dipyrrinato dyes. Density functional theory (DFT) and time-dependent DFT calculations were measured for GS3 and GS10 to understand their structural, electronic and photophysical properties. [ABSTRACT FROM AUTHOR]

We designed and synthesized a new ruthenium complex using terpyridine as an anchoring ligand and BOC ( tert -butyloxycarbonyl) protected bidentate benzimidazole derivative as an ancillary ligand, coded as GS7 . The complex was characterized using 1 H NMR, FTIR, elemental analysis, UV–vis spectrophotometer, and cyclic voltammetry. We also tested photovoltaic performance of this complex for dye-sensitized solar cell (DSSCs). GS7 when used as a sensitizer for DSSCs with iodine triiodide electrolyte, showed a J sc of 15.25 mA cm − 2 , a V oc of 0.576 V, a FF of 0.691 and overall power conversion efficiency of (η) 6.07%. [ABSTRACT FROM AUTHOR]