Search results for "Solar cells"
showing 10 items of 178 documents
Bulk heterojunctions by boramers for plastic photovoltaics
2009
Polymer solar cells with novel fullerene-based acceptor
2004
Abstract Alternative acceptor materials are possible candidates to improve the optical absorption and/or the open circuit voltage of polymer–fullerene solar cells. We studied a novel fullerene-type acceptor, DPM-12, for application in polymer–fullerene bulk heterojunction photovoltaic devices. Though DPM-12 has the identical redox potentials as methanofullerene PCBM, surprisingly high open circuit voltages in the range V OC =0.95 V were measured for OC 1 C 10 -PPV:DPM-12-based samples. The potential for photovoltaic application was studied by means of photovoltaic characterization of solar cells including current–voltage measurements and external quantum yield spectroscopy. Further studies …
Assembling 3D Ordered Architectures in Thin Films for Organic Solar Cells
2010
Enhanced Efficiency of Organic Solar Cells by Thiol-capped Au-Nanoparticles
2015
In this work, we present a study on the effect of thiol-capped AuNPs of various sizesin an organic solar cell.AuNPs have been obtained by laser ablation in liquid solution[2], have been functionalized both with 2-naphthalenethiol and alkanethiol having different length. In addition to bulk heterojunction structures with optimized interpenetrating network of donors and acceptor domains, we have chosen to study planar heterojunctions (PHJs), consisting of three component thin films realized by sequential deposition of P3HT, AuNPs and PCBM from orthogonal solvents.
Enhanced power-conversion efficiency in organic solar cells incorporating polymeric compatibilizers
2018
Improved performance in flexible organic solar cells by using copolymeric phase-separation modulators
2018
One of the main problems related to the low performance of the organic solar cells (OSCs), concerns the low mobility of the materials constituting the heterojunction. Indeed, the poor charge transport in the active layer is the principal cause of a competition between separation and recombination of the photogenerated carriers. In this regard, a major obstacle to enhance OSCs efficiency is developing strategies to optimize the exciton dissociation and, consequently, the charge collection at the electrodes. Donor and acceptor systems must be well mixed on the length scale of 5 – 20 nm (exciton diffusion length) to meet the criteria for efficient exciton dissociation. In addition, the network…
Unconventional materials for light-emitting and photovoltaic applications
2018
La motivación de este trabajo es el problema energético y éste ha sido abordado de dos maneras en esta tesis doctoral: promover un aumento de producción de energía mediante energías renovables junto con una reducción del consumo energético mediante el uso de sistemas más eficientes. Para este propósito, en esta tesis se han desarrollado dispositivos electroluminiscentes y fotovoltaicos novedosos de bajo coste y eficientes. En concreto, el trabajo se ha focalizado en el desarrollo de células electroquímicas emisoras de luz (LECs) emisoras en el rojo e infrarrojo cercano y en la mejora de su estabilidad. Así como en la fabricación de células solares de perovskita de alta eficiencia. Los dispo…
Semitransparent Perovskite Solar Cells with Multilayered Metal Top Electrodes for BIPVs and Tandem Applications
Semitransparent perovskite-based solar cells (ST-PSCs) are highly desired to be integrated into buildings as electricity-generating solar windows in the context of Building-Integrated Photovoltaics (BIPVs), as well as in tandem solar cells combined with other low-bandgap solar cells (e.g. silicon or CIGS) to give enhanced light-harvesting. To fabricate high-performance ST-PSCs, one key challenge is that of replacing the conventional opaque metal top electrodes with suitable transparent alternatives. Recently, dielectric/metal/dielectric (DMD) multilayer architectures have been shown to be suitable candidates as transparent top electrodes, exhibiting ideal characteristics such as mechanical …
Spatial inhomogeneities and defect structures in CIGS and CIS materials: An ab-initio based Monte Carlo study
2011
The chalcopyrite semiconductors CuIn 1−x Ga x Se 2 (CIGS) and CuInSe 2 (CIS) are excellent materials for high efficiency and low cost thin-film solar cells. This is due to the effective absorption of the solar spectrum and the inherent resilience to defects and composition fluctuations. Although the CIGS and CIS material in solar cells is highly inhomogeneous and exhibits a lot of different defects, the cell efficiencies are exceptionally high. If single crystalline absorbers are used, efficiencies are lower. Therefore, studying spatial inhomogeneities and defect structures is of great importance for understanding what supports and what diminishes the efficiency and robustness of the cells.…
Plasmon-enhanced photocurrent in quasi-solid-state dye-sensitized solar cells by the inclusion of gold/silica core–shell nanoparticles in a TiO2 phot…
2013
Direct evidence of the effects of the localized surface plasmon resonance (LSPR) of gold nanoparticles (Au NPs) in TiO2 photoanodes on the performance enhancement in quasi-solid-state dye-sensitized solar cells (DSCs) is reported by comparing gold/silica core–shell nanoparticles (Au@SiO2 NPs) and hollow silica nanoparticles with the same shell size of the core–shell nanoparticles. The Au nanoparticles were shelled by a thin SiO2 layer to produce the core–shell structure, and the SiO2 hollow spheres were made by dissolving the Au cores of the gold/silica core–shell nanoparticles. Therefore, the size and morphology of the SiO2 hollow spheres were the same as the Au@SiO2 NPs. The energy conver…