Unsymmetrical Triphenylamine-Oligothiophene Hybrid Conjugated Systems as Donor Materials for High-Voltage Solution-Processed Organic Solar Cells

The synthesis of unsymmetrical triphenylamine-oligothiophene hybrid conjugated systems bearing dicyanovinyl electron acceptor end-groups is presented. When used as molecular donor materials in solution-processed bulk heteroj­unction solar cells, these compounds lead to efficient devices with very high open-circuit voltages

Two-dimensional topological superconductivity in Pb/Co/Si(111)

Just like insulators can host topological Dirac states at their edges, superconductors can also exhibit topological phases characterized by Majorana edge states. Remarkable zero-energy states have been recently observed at the two ends of proximity induced superconducting wires, and were interpreted as localized Majorana end states in one-dimensional (1D) topological superconductor. By contrast, propagating Majorana states should exist at the 1D edges of two-dimensional (2D) topological superconductors. Here we report the direct observation of dispersive in-gap states surrounding topological superconducting domains made of a single atomic layer of Pb covering magnetic islands of Co/Si(111). We interpret the observed continuous dispersion across the superconducting gap in terms of a spatial topological transition accompanied by a chiral edge mode and residual gaped helical edge states. Our experimental approach enables the engineering and control of a large variety of novel quantum phases. This opens new horizons in the field of quantum materials and quantum electronics where the magnetization of the domains could be used as a control parameter for the manipulation of topological states.Comment: 12 pages, 3 figure

Tristhienylphenylamine - extended dithiafulvene hybrids as bifunctional electroactive species

Extended hybrid conjugated systems based on a trithienylphenylamine core with 1, 2 and 3 peripheral dithiafulvenyl units have been synthesized and studied by cyclic voltammetry and UV-Vis. absorption spectroscopy. Theoretical calculations have also been undergone. The behaviour of these derivatives which depends on the number of dithiafulvene moieties grafted of the central core is cleared up. One polymer, obtained from derivative 3 presents polyelectrochromic properties

Semi-conducteurs Isotropes et Stables pour Cellules solaires Organiques

Date du colloque : 03/2011</p

A tailored hybrid BODIPY–oligothiophene donor for molecular bulk heterojunction solar cells with improved performances

Fixation of a 5-hexyl-2,2′-bithienyl unit on a conjugated BODIPY donor increases the conversion efficiency of the resulting molecular bulk heterojunction solar cells from 1.30 to 2.20%

One step synthesis of D-A-D chromophores as active materials for organic solar cells by basic condensation

Donor-Acceptor-Donor conjugated systems are synthesized in good yield by double condensation of aromatic aldehydes of triarylamines with 2,3-diaminomaleonitrile under microwave activation with trifluoroacetic acid as catalyst. The electronic properties of the compounds are investigated and discussed and a first evaluation of their potential as donor material in organic photovoltaic cells is presented

Soluble and Small Conjugated Molecules as Donor Materials in D:A Bulk-heterojunction Solar Cells

Date du colloque&nbsp;: 09/2009</p

Small and Soluble Molecules as Donors in Bulk-heterojunction Solar Cells

Date du colloque&nbsp;: 04/2010</p