Thermally activated delayed fluorescence emitters in light-emitting electrochemical cells

Thermally activated delayed fluorescence (TADF) represents a very promising singlet harvesting mechanism that permits harvesting of both singlet and triplet excitons in electroluminescent devices. In this chapter, the operating principle of TADF mechanism is introduced. Two major classes of TADF emitters employed in light-emitting electrochemical cell (LEC) devices, small molecule organic compounds, and copper(I) complexes, are discussed in the context of their optoelectronic properties and LEC device performance metrics. A critical outlook for each class of emitters is also provided.</p