About Establis

Earth receives enough sunlight in one hour to satisfy all human needs in a year. Using solar energy will reduce harmful CO2 emissions and resolve the forthcoming energy deficit. The market for stable, mass-produced Organic Solar Cells is estimated at one billion Euros by 2016.

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ESTABLIS will train a team of 11 PhDs and 4 Postdocs to become the scientific leaders in industry and academia. ESTABLIS Fellows will excel.

Research on organic solar cells

Complementarity is at the heart of Establis. To develop Organic Solar Cells requires a concerted combination of physical, synthetic and modelling capabilities. Establis members are working together–across preconceived scientific boundaries–to accelerate the production of Organic Solar Cells.

Partnerships & collaborations

Our Industrial Partners and Associate Partners ensure that the training and technology is economically feasible.

EU support

The EEC is constructively investing more than 3.9 M€ in Establis to train, research and collaborate at the highest international level and ensure our energy platform for the 21st century.

Scientific results

Characterization of the degradation process of Si-PCPDTBT : PC70BM(1:2) blend layers deposited on ITO/glass substrate

M. Secka,b,n, A. Vincze a,b, A. Satka a,b, D. Hasko a, F. Uherek a,b, A. Tournebize cH. Peisert c, T. Chasse c

 

 

a International Laser Centre, Ilkovicova 3, 841 04 Bratislava, Slovakia

b Institute of Electronics and Photonics, Slovak University of Technology, Ilkovicova 3, 812 19 Bratislava, Slovakia

c Eberhard Karls Universität Tübingen, Institut für Physikalische und Theoretische Chemie, Auf der Morgenstelle 18, 72076 Tübingen, Germany

 

Abstract

In organic photovoltaic (OPV), the photoactive layer is the main part, where the energy conversion process takes place. In our work we focus on Si-PCPDTBTRazzC70BM (1:2) photoactive blend layers, where Si-PCPDTBT and PC70BM are the poly[2,6-(4,4-bis(2-ethylhexyl)dithieno[3,2-b:2,3-d]silole)-alt-4,7-(2,1,3 benzothiadiazole)] and [6,6]-phenyl-C71-butyric acid methyl ester, respectively. The mixture of these materials was deposited on the ITO/glass substrate and investigated using different analytical methods such as secondary ion mass spectrometry (SIMS), atomic force microscopy (AFM) and scanning electron microscopy (SEM) before and after the degradation. The different degree degradation of layers measured as % of UV absorbance loss was performed under the illumination at ambient air using a solar simulator (AM 1.5, Xenon arc lamp). SIMS depth profiles reveal a diffusion of atmospheric oxygen through the photoactive layer leading to the photooxidation of organic materials as unveiled from the distribution of selected ions fragments (SO-, NO-, NO2-, SO2- and CO-). AFM and SEM images of the non-degraded sample show a relatively smooth surface. SEM investigations of the degraded layers reveal a homogenous formation of dispersed fibril-like nano-objects at the surface. The formation of such nano-objects may explain the increase of the layer surface oxidation and volatilization during the long-term degradation.

 

Full paper at http://www.sciencedirect.com/science/article/pii/S0927024814004966