Light-Emitting Electrochemical Cells

During the last years, research on light-emitting electrochemical cells (LECs) has literally exploded. Interest for this kind of devices is supported by the specificity of LECs, namely that these devices are among the simplest electroluminescent devices known today. In their simplest form, LECs have the structure of early organic light-emitting diodes (OLEDs), with one layer of organic materials containing mobile ions sandwiched between two metal electrodes. Generally speaking, LECs have several advantages over OLEDs, such as a single-layer configuration, operating at low voltages and allowing the use of air-stable electrodes. Devices can also be entirely solution-processed, what is largely favorable to the development of low-cost and large-area lighting applications in the future. In this chapter, the recent advances and the main remaining challenges concerning LECs are discussed.