Search results for "Organic photovoltaic"
showing 10 items of 17 documents
Ester-functionalized poly(3-alkylthiophene) copolymers : synthesis, physicochemical characterization and performance in bulk heterojunction organic s…
2013
Abstract The introduction of functional moieties in the donor polymer (side chains) offers a potential pathway toward selective modification of the nanomorphology of conjugated polymer:fullerene active layer blends applied in bulk heterojunction organic photovoltaics, pursuing morphology control and solar cell stability. For this purpose, two types of poly(3-alkylthiophene) random copolymers, incorporating different amounts (10/30/50%) of ester-functionalized side chains, were efficiently synthesized using the Rieke method. The solar cell performance of the functionalized copolymers was evaluated and compared to the pristine P3HT:PCBM system. It was observed that the physicochemical and opt…
Efficient microwave-mediated synthesis of fullerene acceptors for organic photovoltaics
2014
Two different processes, namely the Bamford–Stevens and [4 + 2] Diels Alder reactions, have been optimized under microwave irradiation for the functionalization of fullerenes. In this manner, all the main C60- and C70-based acceptor derivatives for organic solar cells such as PCBM, DPM, BHN and ICBA, have been prepared in higher yields and shorter reaction times with respect to the reported data. These findings represent a step forward toward the wide production of cheaper organic solar cells as a consequence of the cost abatement of the acceptors given by higher yields, lower waste production, and reduced reaction time which means a strong energy saving.
Thiophene pyrenyl derivatives for the supramolecular processability of single-walled carbon nanotubes in thin film heterojunction
2017
Abstract A major problem for the use of single-wall carbon nanotubes (SWCNTs) in electronic devices relates to their poor processability. Chemical modification inevitably introduces defects in the nanotube lattice, resulting in a loss of electronic properties. In this contest, we report on a supramolecular approach with the aim of increasing the dispersion of SWCNTs in solution and in organic semiconductor matrices by ensuring the optoelectronic properties. In particular, new pyrenyl derivatives of thiophene have been synthesized and used to improve the solubility of SWCNTs for electron transfer in thin film heterojunction with poly(3-hexylthiophene) (P3HT) as donor system. Photoinduced ele…
A Very Low Band Gap Diketopyrrolopyrrole-Porphyrin Conjugated Polymer
2017
International audience; A porphyrin-diketopyrrolopyrrole-containing polymer (poly(porphyrin-diketopyrrolopyrrole) (PPDPP)) shows impressive molar absorption coefficients from lambda=300 to 1000 nm. The photophysical and structural properties of PPDPP have been studied. With PPDPP as the electron donor and [ 6,6]phenyl C-71 butyric acid methyl ester (PC71BM) as the electron acceptor, the bulk heterojunction polymer solar cell showed overall power conversion efficiencies of 4.18 and 6.44% for as-cast and two-step annealing processed PPDPP: PC71BM (1: 2) active layers, respectively. These results are quite impressive for porphyrin-containing polymers, especially when directly included in the p…
Donor/Acceptor Heterojunction Organic Solar Cells
2020
The operation and the design of organic solar cells with donor/acceptor heterojunction structure and exciton blocking layer is outlined and results of their initial development and assessment are reported. Under halogen lamp illumination with 100 mW/cm2 incident optical power density, the devices exhibits an open circuit voltage VOC = 0.45 V, a short circuit current density JSC between 2 and 2.5 mA/cm2 with a fill factor FF &asymp
Porphyrins and BODIPY as Building Blocks for Efficient Donor Materials in Bulk Heterojunction Solar Cells
2017
International audience; Advances in the synthesis and application of highly efficient polymers and small molecules over the last two decades have enabled the rapid advancement in the development of organic solar cells and photovoltaic technology as a promising alternative to conventional solar cells, based on silicon and other inorganic semiconducting materials. Among the different types of organic semiconducting materials, porphyrins and BODIPY-based small molecules and conjugated polymers attract high interest as efficient semiconducting organic materials for dye sensitized solar cells and bulk heterojunction organic solar cells. The highest power conversion efficiency exceeding 9% has be…
Donor–Acceptor Interfaces by Engineered Nanoparticles Assemblies for Enhanced Efficiency in Plastic Planar Heterojunction Solar Cells
2016
Precisely positioning functionalized gold nanoparticles assemblies at planar donor-acceptor interfaces results in 14-fold enhancement of power conversion efficiency in P3HT/PCBM organic solar cells on plastic (ITO/PET) substrates. This result has been achieved by employing naphthalenethiol-capped gold nanoparticles (NT-Au-NPs) produced by laser ablation in liquid and size varied in the 10-30 nm range. Upon surface functionalization with the aromatic thiol, these particles self-assemble in submicrometer aggregates, which give increased light scattering. When these aggregates are deposited in the planar heterojunction between the donor and the acceptor systems, the localized scattering leads …
Buckyballs
2013
Buckyballs represent a new and fascinating molecular allotropic form of carbon that has received a lot of attention by the chemical community during the last two decades. The unabating interest on this singular family of highly strained carbon spheres has allowed the establishing of the fundamental chemical reactivity of these carbon cages and, therefore, a huge variety of fullerene derivatives involving [60] and [70]fullerenes, higher fullerenes, and endohedral fullerenes have been prepared. Much less is known, however, of the chemistry of the uncommon non-IPR fullerenes which currently represent a scientific curiosity and which could pave the way to a range of new fullerenes. In this revi…