Search results for " Solar cell"
showing 10 items of 309 documents
Electro-optical characterization of ruthenium-based dye sensitized solar cells: A study of light soaking, ageing and temperature effects
2017
Abstract 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 …
One diode circuital model of light soaking phenomena in Dye-Sensitized Solar Cells
2018
Abstract 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…
Organic Dye Bearing Asymmetric Double Donor-π-Acceptor Chains for Dye-Sensitized Solar Cells
2011
A novel efficient metal free sensitizer containing asymmetric double donor-π-acceptor chains (DC) was synthesized for dye-sensitized solar cells (DSSCs). Comparing to 3.80%, 4.40% and 4.64% for the DSSCs based on the dyes with single chain (SC1, SC2) and cosensitizers (SC1 + SC2), the overall conversion efficiency reaches 6.06% for DC-sensitized solar cells as a result of its longer electron lifetime and higher incident monochromatic photon-to-current conversion efficiency.
Electrical and photoelectrical measurements on ZnO-Nanowires coated with PEDOT:PSS for Dye-Sensitized Solar Cells
2011
ABSTRACTDye-sensitized solar cells composed of an n-doped ZnO nanowire array and a p-doped polymer layer appears to be a promising candidate for low-cost production of environment-friendly solar cells. In this work, we investigate hybrid devices consisting of a transparent conducting oxide (TCO) substrate, ZnO-nanowires (ZnO-NW) or a sol-gel prepared ZnO layer, a ruthenium dye (N719) and a PEDOT:PSS or P3HT layer. The dense polycrystalline ZnO layer is able to prevent short circuits, which have a strong effect on the performance of the solar cells. This is demonstrated by the use of only the ZnO layer which improves the open circuit voltage by a factor of 2 and the efficiency by a factor of…
2,3-Dipentyldithieno[3,2-f:2′,3′-h]quinoxaline-Based Organic Dyes for Efficient Dye-Sensitized Solar Cells: Effect of π-Bridges and Electron Donors o…
2015
Five novel metal-free organic dyes DQ1-5 containing a dipentyldithieno[3,2-f:2',3'-h]quinoxaline (DPQ) unit were synthesized and applied in dye-sensitized solar cells (DSSCs), where DPQ was employed as a π-spacer for the first time. Their photophysical, electrochemical, and theoretical calculations and photovoltaic properties were systematically investigated. All the five dyes show broad photoresponse. Especially the absorption edges of DQ3-5 extend to 800 nm on the TiO2 films. The inserted electron-rich unit 3,4-ethylenedioxythiophene or electron-withdrawing group benzothiadiazole (BTD) in DPQ-based dyes can greatly influence the optoelectronic properties of the dyes. In addition, the diff…
Effect of methaacrylic acid on the structure of Eu:YAG-PMMA composites
2014
Polymeric composites of lanthanide-doped materials were recently considered as potential candidates for the development of light emitting diodes, lasers and luminescent concentrators for solar cells. In particular, nanoparticles of yttrium aluminum garnet (YAG) doped with cerium ions embedded in polymetylmetacrylate (PMMA) have been valuable for white LED devices [1,2]. Different structures and micromechanical properties have been observed when the methacrylic acid (MAA) is present in the composite. With the aim to understand the effect of MAA on the composite structure, a series of Eu:YAG composites prepared by in situ polymerization starting from mixtures of MAA and methylmetacrylate (MMA…
Simultaneous determination of carrier lifetime and electron density-of-states in P3HT:PCBM organic solar cells under illumination by impedance spectr…
2010
We report new insights into recombination kinetics in poly(3-hexylthiophene):methanofullerene (P3HT:PCBM) bulk heterojunction (BHJ) solar cells, based on simultaneous determination of the density of states (DOS), internal recombination resistance, and carrier lifetime, at different steady states, by impedance spectroscopy. A set of measurements at open circuit under illumination was performed aiming to better understand the limitations to the photovoltage, which in this class of solar cells remains far below the theoretical limit which is the difference between the LUMO level of PCBM and the HOMO of P3HT (∼1.1 eV). Recombination kinetics follows a bimolecular law, being the recombination ti…
Synthesis and characterization of zinc carboxy–porphyrin complexes for dye sensitized solar cells
2018
Two zinc porphyrins, 2 and 8, have been synthesized. Porphyrin 8 displays better electronic communication between the dye and the TiO2 electrode. Photophysical measurements and electrochemistry experiments suggest that both porphyrins are very promising sensitizers for dye-sensitized solar cells (DSSCs). It was found that their molecular orbital energy levels favor electron injection and dye regeneration in DSSCs. Solar cells sensitized by 2 and 8 were fabricated, and it was found that they show power conversion efficiencies (PCEs) of 5.27% and 7.13%, respectively. Photovoltaic measurements (J–V curves) together with the incident photon-to-electron conversion efficiency spectra of the two c…
Analyses of innovative glass blocks for BIPV: assessment of thermal and optical performance
2015
This paper illustrates the results of the performance analyses conducted on an innovative glass block integrated with thirdgeneration dye-sensitised solar cells (DSCs), designed to enable the construction of translucent and sustainable building envelopes. The analyses include the simulation of both thermal and optical performance with regard to different configurations of the photovoltaic (PV)-integrated glass block, and the results obtained are presented using two different programs: Comsol Multiphysics and WINDOW. The configurations may differ – for example, because of the position of the module inside the glass block, the type of DSC module used (composition, transparency, design) and th…
Energy Optimization of BIPV Glass Blocks: a Multi-software Study
2017
Abstract The aim of this paper is to show the results of the performance analyses carried out on four patented glass block configurations integrated with third-generation Dye-sensitized Solar Cell (DSC) modules. The analyses take into account the thermal, optical and electrical performance by using three different software (COMSOL Multiphysics, WINDOW, Zemax), also enabling to take into consideration the peculiar three-dimensional geometry of this innovative glazed product. Starting from these results, new configurations improved as for the thermal insulation, are also introduced and studied, in order to make further considerations about the applicability of this building component for the …