vub wapenschild

Organic photovoltaics

The main objective is to achieve a more profound understanding of the OPV blend nanomorphology-performance relationship by means of the physicochemical characteristics of the active components (solubility, molecular weight, polydispersity, aggregation phenomena, crystallization kinetics, kinetics of phase separation). Unravelling this relationship provides a fundamental toolbox to engineer the molecular structure of the materials involved, and the resulting blend nanomorphology. This would lead to a rational design of materials, and contribute to a unifying model that truly links performance to molecular structure and to constitution/composition, considering intermixed or phase-separated ordered/disordered/aggregated (nano)domains.

Projects

Phase behaviour and rheology of solutions and blends of conjugated polymers

Phase behaviour and rheology of solutions and blends of conjugated polymers

The goal of this project is to get insight in the fundamentals of the solution and phase behaviour of conjugated polymers in specific solvents, on the one hand, and to extend this knowledge to the rheological behaviour under shear or extension, on the other hand. This is extended from solutions of conducting polymers to mixtures of conjugated polymers with fullerene derivatives. These material ...

RAtional DEsign of blends for bulk heterojunction SOLar cells (RADESOL)

RAtional DEsign of blends for bulk heterojunction SOLar cells (RADESOL)

The main goal of the project is to unravel nanomorphology formation at the molecular level and its effect on device performance beyond the state-of-the-art by an integrated experimental effort and a unique combination of equipment and expertises, aiming at the study of blends via advanced thermal analysis, solid-state NMR, and X-ray diffraction and ptychography 3D imaging techniques, combined ...

 Nanostructuring, morphological stability, and mechanism of charge transfer in conjugated polymer/fullerene blends for organic photovoltaic cells. An experimental and theoretical study

Nanostructuring, morphological stability, and mechanism of charge transfer in conjugated polymer/fullerene blends for organic photovoltaic cells. An experimental and theoretical study

The aim of this project is to contribute to the fundamental insights into the mechanisms and criteria that affect the efficiency and stability of 'exciton' solar cells, based on the 'bulk heterojunction' concept. In this type of photovoltaic cells, foto-induced excitons (hole-electron pairs) that are formed in a donor phase of a phase separated system, must diffuse towards the (nano)interface ...

Molecular mixing in bulk heterojunction organic solar cells - nanomorphology vs performance

The photovoltaic behavior of organic bulk heterojunction (BHJ) blends of conjugated (donor) polymers and fullerene (acceptor) derivatives has been subject of many studies in fundamental chemistry and physics since its initial discovery in 1995. From the general understanding at this moment, the nanomorphology of the active layer blend seems to be crucial. The latter is the result of a complex ...