BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Unraveling the Photophysical Properties of Organic Semiconductors 
 - Professor Natalie Banerji\, University of Fribourg
DTSTART:20151125T143000Z
DTEND:20151125T153000Z
UID:TALK60887@talks.cam.ac.uk
CONTACT:Stuart Higgins
DESCRIPTION:Organic semiconductors offer numerous advantages compared to t
 heir inorganic counterparts\, such as\nlow-cost manufacturing\, flexibilit
 y and lightweight. One important application is their use in new\ngenerati
 on solar cells (Figure 1). The active layer of such photovoltaic devices o
 ften consists of a\nconjugated polymer\, blended with a fullerene derivati
 ve in a solid-state thin film. In order to understand\nhow those solar cel
 ls work and to improve their performance\, it is important to investigate 
 the lightmatter\ninteractions of the organic materials. We have done so by
  using a palette of experiments\,\nspanning from ultrafast spectroscopy\, 
 via Stark effect methods\, terahertz techniques\, photocurrent\nmeasuremen
 ts\, to nanoscale mobility characterization.\n\nI will briefly present our
  insights about the excited-state properties of conjugated polymers\, with
  focus on the importance of short-lived delocalization [1\,2]. I will then
  move on to discuss the correlation\nbetween the phase-morphology of polym
 er:fullerene blends and the photogeneration of free charge\ncarriers [3-5]
 . Indeed\, our work has shown that this essential step in solar cell funct
 ioning is largely\ndetermined by the way in which the polymer and fulleren
 e arrange at the nanoscale. Results\nwill be presented for the pBTTT and P
 BDTTPD polymers\, as obtained by transient absorption\, electromodulated\n
 differential absorption and terahertz spectroscopy. Finally\, I will give 
 an overview of our\nmost recent studies about organic and hybrid semicondu
 ctors [6]\, not just applied to photovoltaics\, but\nalso to transistors a
 nd biological sensors.\n[1] N. Banerji\, J. Mater. Chem. C. 2013\, 1\, 305
 2.\n[2] M. Scarongella\, A. Laktionov\, U. Röthlisberger\, N. Banerji\, J
 . Mater. Chem. C. 2013\, 1\, 2308.\n[3] M. Scarongella\, J. De Jonghe-Riss
 e\, E. Buchaca-Domingo\, M. Causa’\, Z. Fei\, M. Heeney\, J.-E.\nMoser\,
  N. Stingelin\, N. Banerji\, J. Amer. Chem. Soc. 2015\, 137\, 2908.\n[4] M
 . Scarongella\, A. A. Paraecattil\, E. Buchaca-Domingo\, J. D. Douglas\, S
 . Beaupre\, T. McCarthy-\nWard\, M. Heeney\, J.-E. Moser\, M. Leclerc\, J.
 -M. Fréchet\, N. Stingelin\, N. Banerji\, J. Mater. Chem.\nA. 2014\, 2\, 
 6218.\n[5] A. A. Paraecattil\, N. Banerji\, J. Amer. Chem. Soc. 2014\, 136
 \, 1471.\n[6] J. Brauer\, Y. H. Lee\, M. K. Nazeeruddin\, N. Banerji\, J. 
 Phys. Chem. Lett. 2015\, 6\, 3675.
LOCATION:Kapitza Building Seminar Room\, Cavendish Laboratory\, Department
  of Physics
END:VEVENT
END:VCALENDAR