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Molecularly Engineered Polymer Leds

Published online by Cambridge University Press:  16 February 2011

Stephen C. Moratti
Affiliation:
University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
Donald C. Bradley
Affiliation:
Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 OHE, U.K.
Richard H. Friend
Affiliation:
Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 OHE, U.K.
Neil C. Greenham
Affiliation:
Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 OHE, U.K.
Andrew B. Holmes
Affiliation:
University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
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Abstract

Polymeric light emitting devices may be fabricated from a simple structure consisting of a low work function cathode (typically calcium or Magnesium), a conjugated semiconducting polymer and a transparent anode (typically indium-tin oxide). Optimum device efficiencies require the balanced injection of electrons and holes. This paper describes the application of molecular engineering in the design of a family of poly (cyanoterephthalylidenene) s which show increased electron affinity over the unsubstituted analogue [poly (p-phenylenevinylene) PPV]. In particular these polymers as the emissive layer in a bilayer device with indium tin oxide (ITO, positive transparent contact) and aluminum (stable negative contact) and PPV as a hole transporting layer exhibit internal efficiencies up to 4%.

Type
Research Article
Copyright
Copyright © Materials Research Society 1994

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