The light-emitting electrochemical cell (LEC) is an area-emitting device, which features a complex turn-on process that ends with the formation of a p-n junction doping structure within the active material. This in-situ doping transformation is attractive in that it promises to pave the way for an unprecedented low-cost fabrication of thin and light-weight devices that present efficient light emission at low applied voltage. In this review, we present recent insights regarding the operational mechanism, breakthroughs in the development of scalable and adaptable solution-based methods for cost-efficient fabrication, and successful efforts toward the realization of LEC devices with improved efficiency and stability.
Keywords: Conjugated polymer; Direct fabrication on complex surfaces; Doping; Efficient operation; Electrolyte; Ionic transition metal complex; Large-area emission; Light-emitting electrochemical cell; Light-weight and flexible device architectures; Long-term stability; P-n junction formation; Solution-based fabrication.