Organic light-emitting diodes (LEDs) based on Langmuir-Blodgett films containing rare-earth complexes

In this paper we report the construction of an organic light-emitting diode (LED) containing a rare-earth molecular complex that was deposited as a Langmuir-Blodgett (LB) film. The complex is a donor-conjugated π-electron system acceptor (D-π-molecular cation coupled to a monovalent anion containing a trivalent rare-earth (Nd3+) cation surrounded by four organic singly charged anionic ligands. Devices were fabricated by LB deposition of multilayer films onto an indium-tin oxide (ITO)-coated glasls substrate on top of which aluminium was evaporated to form the diode structure. Such devices are found to electroluminesce when subjected to a forward bias of a few volts. We present here the electrical and optical characteristics of the device.