Cookies Policy
X

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here

Space charge and polarization effects upon doping organic light-emitting diodes with pyran-containing donor-acceptor molecules

No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this article

+ Tax (if applicable)
Add to Favorites
You must be logged in to use this functionality

image of Research on Chemical Intermediates

Doping of organic light-emitting devices using highly luminescent molecules is a well-established strategy to improve brightness, efficiency and lifetime or to adjust emission color and color purity. Laser dyes from the pyran-containing donor-acceptor family are particularly interesting for emission in the yellow and red spectral domain. In solution, these polar dyes show marked solvatochromic shifts in the absorption and emission. The fluorescence quantum efficiency also depends strongly on solvent polarity, which suggests the occurrence of twisted excited states. In thin solid films such as the ones used in the fabrication of organic light-emitting diodes, additional effects have to be considered. When pyran derivatives are used as doping molecules in a Tris(8-hydroxyquinolinato)aluminium (Alq3) host matrix, the emission color is highly dependent on doping concentration. This is attributed to polarization effects induced by the doping molecules themselves. For some pyran derivatives, such as 4-(dicyanomethylene)-2-methyl-6-{2[(4-diphenylamino) phenyl]ethenyl}-4H-pyran (DCM-TPA), the electroluminescence spectrum is not pure and shows a green Alq3 shoulder, even at high concentrations. We have shown that these effects depend on the position of the frontier orbital energy levels with respect to those of the host. Charge carrier trapping by the doping molecules influences the charge density distribution. At high current densities, this can lead to a shift of the recombination zone out of the doped region. To impede charge recombination processes taking place in the undoped host matrix, charge blocking layers efficiently confine the recombination zone and give rise to increased efficiency.

10.1163/1568567041280863
/content/journals/10.1163/1568567041280863
dcterms_title,pub_keyword,dcterms_description,pub_author
6
3
Loading
Loading

Full text loading...

/content/journals/10.1163/1568567041280863
Loading

Data & Media loading...

http://brill.metastore.ingenta.com/content/journals/10.1163/1568567041280863
Loading

Article metrics loading...

/content/journals/10.1163/1568567041280863
2004-06-01
2016-12-03

Sign-in

Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Subscribe to ToC alert
  • Get permissions
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
     
    Research on Chemical Intermediates — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation