title: Influence of the molecular weight and size dispersion of the electroluminescent polymer on the performance of air-stable hybrid light-emitting diodes.
abstract: The influence of the chain length and the molecular weight distribution of the electroluminescent polymer on the carrier transport properties and morphology of air stable hybrid light-emitting diodes is reported. It is found that variations between diverse as-received commercial batches play a major role in the performance of the devices, whose maximum luminance can differ up to 2 orders of magnitude. Through complementary optoelectronic, structural, and morphological characterization techniques, we provide insights into the relationship between charge dynamics and the structure of polymeric electroluminescent materials. The carrier dynamics are found to be dominated by both the polymeric chain length and the hole transport, which in turn is dependent on the concentration of trap states. Furthermore, the chain length is seen to affect the morphology of the active layer.
authors.affiliation: Fundació CETEMMSA , Avenida Ernest Lluch 36, E-08302 Mataró, Spain.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Martinez-Ferrero
authors.forename: Souren
authors.initials: S
authors.lastname: Grigorian
authors.forename: James W
authors.initials: JW
authors.lastname: Ryan
authors.forename: Werther
authors.initials: W
authors.lastname: Cambarau
authors.forename: Emilio
authors.initials: E
authors.lastname: Palomares
keywords: F8BT; charge carrier mobility; electroluminescent polymers; hybrid light-emitting diodes; molecular weight; polidispersity index