Organic light-emitting diodes (OLEDs)

Organic light-emitting diodes (OLEDs): Materials, devices and applications
Edited by A Buckley, University of Sheffield, UK
Woodhead Publishing Series in Electronic and Optical Materials No. 36

Tuning the colour and efficiency of OLEDs
M. COCCHI, National Research Council of Italy and Consortium MIST E-R scrl, Italy

Abstract: This chapter provides an overview on the road map used to tune
the colour and efficiency of organic light emitting devices (OLEDs). A
comprehensive introduction to the potential of OLED technology is first
provided. Then attention is given on one way to obtain a multi- emission by a
single phosphor, making use of platinum(II) complexes as phosphorescent
emitters. OLEDs prepared using highly luminescent Pt(II) complexes
containing cyclometallating bidentate and terdentate ligands are presented.
These complexes with square planar configuration often lead to stacking and
formation of luminescent aggregates. A brief description of the nature of these
bimolecular exited states is reported. Taking advantage of this behaviour, many
types of OLEDs, such as White OLED (WOLED), Near-InfraRed OLED
(NIROLED) and Plant Growth OLED (PGOLED), are shown. Such devices
fulfil the requirements to become an important part of ‘green photonics’.