Study and comparison of conducting polymer hole injection layers in light emitting devices
2005 (English)In: Organic electronics, ISSN 1566-1199, Vol. 6, no 1, 21-33 p.Article in journal (Refereed) Published
A set of polyaniline- and poly(3,4-ethylene dioxythiophene)-based materials were studied as hole injection layers in polymer light emitting devices. The choice of polymeric counterion/dopant poly(styrenesulfonic acid), and poly(acrylamido-2-methyl-1-propanesulfonic acid), and poly(acrylamide) blended with polyaniline/poly(acrylamido-2-methyl-1-propanesulfonic acid) was found to influence both work function and film morphology, which in turn affects device performance. The work functions of the polymer films spanned the range of over 1 eV and the surface region of the films were found to be low in conducting polymer content compared to the bulk. This was particularly the case of the polyaniline/poly(acrylamido-2-methyl-1-propanesulfonic acid) blended with poly(acrylamide) which showed device efficiency equal to that of the poly(3,4-ethylene dioxythiophene)–poly(styrenesulfonic acid) reference. The turn on voltage, however, was significantly larger, likely due to the insulating poly(acrylamide)-rich surface region of the polyaniline/poly(acrylamido-2-methyl-1-propanesulfonic acid)/poly(acrylamide) film. The polymer blend of polyaniline/poly(styrenesulfonic acid) yielded the highest work function (5.5 ± 0.1 eV).
Place, publisher, year, edition, pages
2005. Vol. 6, no 1, 21-33 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-32255DOI: 10.1016/j.orgel.2005.02.001Local ID: 18135OAI: oai:DiVA.org:liu-32255DiVA: diva2:253077