Organic Small-Molecule Materials for Organic Light-Emitting Diodes

This chapter reviews most of the important small-molecular materials used in OLEDs. In many cases, where such data is available, we will also describe the related device structures and electroluminescence performance associated with those materials. Organic light-emitting diodes (OLED) devices are fabricated on a glass, plastic, metal, or ceramic substrate as a multilayer-stacked structure. The simplest manifestation of an OLED is a sandwich structure consisting of an emission layer between an anode and a cathode. The chapter summarizes the light-generating mechanism of OLEDs. Since an OLED is a multilayer device structure, the interfacial electronic structure at the organic–metal and organic–organic interfaces plays an important role in the devices. The chemical and photo-physical characteristics of the emissive material itself lead to categorization of OLEDs containing them into two main types: small molecule light-emitting diodes and polymer light-emitting diodes.