Effect of molecular weight on the efficiency of poly(N-vinylcarbazole)-based polymer light-emitting diodes
Title | Effect of molecular weight on the efficiency of poly(N-vinylcarbazole)-based polymer light-emitting diodes |
Publication Type | Journal Article |
Year of Publication | 2011 |
Authors | Cai, M, Xiao T, Chen Y, Hellerich E, Liu R, Shinar R, Shinar J |
Journal Title | Applied Physics Letters |
Volume | 99 |
Pages | 203302 |
Date Published | 11/14 |
ISBN Number | 0003-6951 |
Accession Number | ISI:000297786500062 |
Keywords | devices, LAYER |
Abstract | Polymer light-emitting diodes based on poly(N-vinylcarbazole) (PVK) with molecular weights M(W) of 1.1 x 10(6) and similar to 7.5 x 10(4) are compared. For devices without an electron transport layer (ETL), the high M(W) PVK yields higher external quantum efficiency (0.67% vs 0.18%), but for devices with an ETL, the low MW PVK yields higher efficiency (1.13% vs 0.83%). This intriguing difference is believed to result from higher energetic disorder in the high M(W) polymer and different recombination zone-quenching metal electrode distances, in agreement with Konezny et al. [Appl. Phys. Lett. 97, 143305 (2010)]. (C) 2011 American Institute of Physics. [doi:10.1063/1.3659467] |
URL | <Go to ISI>://000297786500062 |
DOI | 10.1063/1.3659467 |
Alternate Journal | Appl Phys Lett |