Since the beginning of Organic Light-Emitting Diodes (OLEDs), blue emission has attracted the most attention and many research groups worldwide have worked on the design of materials for stable and highly efficient blue OLEDs. However, almost all the high-efficiency blue OLEDs using fluorescent materials are multi-layer devices, which are constituted of a stack of organic layers to improve the injection, transport and recombination of charges within the emissive layer. Despite the technology is mastered, it suffers from a real complexity, a high cost, and is time-consuming. Simplifying the multi-layer structure with single-layer one, simplest devices only made of the electrodes and the emissive layer has appeared as an appealing strategy for this technology. However, removing the functional organic layers of an OLED stack leads to a dramatic decrease of the performance and reaching high efficiency blue single-layer OLEDs has required intense researches and especially in term of materials design. We report herein an exhaustive review on blue emitting fluorophores, which have been incorporated in single-layer OLEDs and discuss the links between their electronic properties and the devices performance. We thus draw a structure/properties/device performance relationship map of interest for the future design of organic materials.
Cyril Poriel - cyril [dot] porieluniv-rennes1 [dot] fr,
Joelle Rault-Berthelot - joelle [dot] rault-berthelotuniv-rennes1 [dot] fr
Univ Rennes, CNRS, ISCR-6226, F-35000 Rennes, France
C. Poriel and J. Rault - Berthelot, Adv. Funct. Mat., 2020, in press. (10.1002/adfm.201910040)
‘Hot Topic Organic Electronics’