@phdthesis{ArjonaEsteban2015,
  author    = {Arjona Esteban, Alhama},
  title     = {Merocyanine Dyes as Organic Semiconductors for Vacuum-processed Solar Cell and Transistor Devices},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129096},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {The present thesis comprises the synthesis of new functional merocyanine dyes, the study of their electro-optical properties as well as solid state packing and their application as p-type semiconductor materials in transistor and solar cell devices. The absorption properties of the obtained compounds could be modified by variation of the donor unit, the introduction of electron-withdrawing substituents in the acceptor unit or elongation of the polymethine chain. For a particular dye, the absorption band could be shifted by more than 160 nm by increasing the solvent polarity due to a conformational switch between a merocyanine-like and a cyanine-like structure. Single crystal analyses revealed that the studied dyes tend to pack either in an antiparallel fashion forming dimers with no overall dipole moment or in a staircase-like pattern where the dipole moments point to the same direction and are only balanced by another staircase oriented in the opposite direction (stair dimer). With respect to application as semiconductor materials, the latter packing arrangement resulted most favorable for charge carrier mobility. We concluded that this packing motif is preserved in the solar cell devices, where the selenium-containing dye afforded the highest performance of this series for an optimized planar-mixed heterojunction solar cell (6.2 \%).},
  subject      = {Merocyanine},
  language  = {en}
}