Vladimir Dyakonov
Who are you?
Vladimir Dyakonov
I am Vladimir Dyakonov, a professor of experimental physics at the University of Würzburg, Germany. At the time the Nanotechnology paper was published I was doing research at the University of Oldenburg, closely collaborating with the solar cell group of Professor Jürgen Parisi. Moreover, Oldenburg is quite close to the University of Groningen, where 'Mr PCBM' Professor Kees Hummelen was working and who provided us with his 'magic' fullerenes, which by the way remain the best performing acceptors in polymer solar cells until now. Dana Chirvase, a PhD student, did an excellent job in the lab making devices.
What prompted you into this field of research?
In 1997, I joined a newly founded lab at the University of Linz, Austria, as a post-doctoral Lise-Meitner-Fellow. The head was Professor Serdar Sariciftci, who moved back to Europe from Santa Barbara and started building-up an 'European HQ' of organic photovoltaics (OPV). He inspired me to do plastic solar cells. Two years later I started my OPV group in Oldenburg.
Can you briefly describe what your paper reports and the impact that it has had on the field?
Solid blends of semiconducting polymers and fullerenes sound easy, but they are not easy at all and were one of the difficult to control OPV issues. The polymers and fullerenes interact with each other to form films of several of tens of nanometers, which people call 'morphology'. We decided to monitor the morphology by varying several parameters in a systematic way, i.e. by changing the fullerene load, processing temperature and seeing what the device performance will be. The result was the optimal recipe to make solar cells with the polymer P3HT (which was extremely popular at that time) and PCBM. A good resonance in the community, displayed by more than 40 citations a year, shows these results have some practical relevance for other groups. And we were lucky to publish this work before other groups. Nanotechnology is one of the fastest publishing journals, which does not mean we did not have problems with reviewers. All's well that ends well and we were very happy to overcome this, too.
Can you detail what direction your research went following on from this article and, if applicable, how the results reported in this article helped to influence this?
The OPV remains one of the most exciting interdisciplinary research fields. The record efficiency is now above 10%. Although the best solar cells are not built with the polymers we investigated that time, the ideas and concepts remain the same. Since 2004 our understanding of the complex physics behind organic PV grew up, which we recently summarized in another paper recently published with IOP Publishing (Reports On Progress In Physics 73 (2010) which has a good chance to take over our 2004 paper in terms of citations in the coming years
Co-authors on the paper:
Kees Hummelen
Jürgen Parisi