Bonn 2010 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
AKE: Arbeitskreis Energie
AKE 1: Erneuerbare Energien I: Photovoltaik
AKE 1.3: Talk
Monday, March 15, 2010, 15:00–15:15, JUR D
Organic solar cells based on small molecules — •Jan Meiss, David Wynands, Christiane Falkenberg, Ronny Timmreck, Roland Gresser, Steffen Pfützner, Karl Leo, and Moritz Riede — Institut für angewandte Photophysik, TU Dresden
In recent years, organic solar cells (OSCs) have attracted considerable interest from both the research community and industry. Currently, several start-ups are working on the commercialisation of this type of photovoltaic technology. Advantages of OSCs are low material and energy consumption during production, allowing for light-weight, large-area, and flexible modules. Yet, there are still open questions on the fundamental physics, e.g. the process of free charge carrier generation; furthermore, device lifetime and power conversion efficiency have to be improved. One very promising approach for OSCs uses thermal evaporation of small molecules in vacuum to create organic stacks in the p-i-n architecture, i.e. an intrinsic absorber layer sandwiched between p- and n-doped transport layers. Vacuum deposition of the various layers in the OSC enables an easy stacking of many layers, which is essential for tandem solar cells. The controlled doping allows for an active control of the Fermi level in the doped layers, increases conductivity of transport layers by orders of magnitude, and creates ohmic contacts to the electrodes. Standard absorber materials are metal-phthalocyanines and C60 as electron donor and acceptor, respectively. Furthermore, there is a growing number of new materials. Material and device optimisation have recently lead to certified efficiencies of more than 6% on a device area exceeding 1cm2 with promising device lifetimes.