de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Efficient organic photovoltaics from soluble discotic liquid crystalline materials

MPS-Authors
http://pubman.mpdl.mpg.de/cone/persons/resource/persons47860

Fechtenkötter,  Andreas
MPI for Polymer Research, Max Planck Society;

http://pubman.mpdl.mpg.de/cone/persons/resource/persons48459

Müllen,  Klaus
MPI for Polymer Research, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Schmidt-Mende, L., Fechtenkötter, A., Müllen, K., Friend, R. H., & MacKenzie, J. D. (2002). Efficient organic photovoltaics from soluble discotic liquid crystalline materials. Physica E, 14(1-2), 263-267.


Cite as: http://hdl.handle.net/11858/00-001M-0000-000F-6640-8
Abstract
Two different types of soluble discotic liquid crystalline materials and a crystalline perylene dye have been used to create, directly from solution, photovoltaic devices which are compared in this work. Self-organisation of the soluble electron-accepting perylene derivative and the soluble liquid crystalline (LC) discotic material which is stable in a LC phase at room temperature (HBC-PhC12) leads to segregated structures optimised for charge separation and transport in photovoltaic device structures. High external quantum efficiencies up to 34% near 490 nm have been reached. The high efficiencies result from efficient photo-induced charge transfer between the materials as well as effective transport of electrons and holes to the cathode and anode through segregated perylene and the discotic peri-hexabenzocoronene p- system. Atomic force microscopy and device characteristics suggest that the driving force for phase separation and surface energy effects during spin coating of the HBC-PhC12:perylene blend result in a spontaneous vertical segregation of the HBC and the perylene normal to the plane of the spun film. This represents a nearly ideal, self-organised structure in which vertical segregation of charge transport layers coexist with a high interfacial area between the two charge transfer components. This vertical segregation has not been observed in the spin-coated blends where the HBC-PhC12 is replaced by HBC- C-8(*). One probable reason for this may be the different phase stability of the LC phase in the HBCs, which leads to different film-forming properties and film morphologies. (C) 2002 Elsevier Science B.V. All rights reserved.