Light-Emitting Electrochemical Cells: A Review on Recent Progress

Abstract

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.

Ion Transport beyond the Polyether Paradigm: Introducing Oligocarbonate Ion Transporters for Efficient Light‐Emitting Electrochemical Cells

“…In order to realize an optimum doping structure over the entire device area, it is therefore desirable that the electrolyte and the emitter are intimately mixed within the active material. If not, it is probable that the ion‐rich regions will exhibit a too high doping concentration that results in severe exciton quenching and self‐absorption, while the ion‐poor regions will suffer from a too low doping concentration with concomitant poor injection and transport . In this context, we note that previous studies on ether‐based electrolytes[9b,c,13b,d] have arrived at the same conclusion, viz., that an oligomeric ion transporter outperforms a structurally similar polymeric ion transporter in LEC devices.…”

On the Design of Host–Guest Light‐Emitting Electrochemical Cells: Should the Guest be Physically Blended or Chemically Incorporated into the Host for Efficient Emission?

“…The efficient operation of a LEC is dependent on that the electroactive compound can be both p‐type doped and n‐type doped 1a,14. As the observed oxidation and reduction reactions in CV are good indicators of electrochemical p‐type doping and n‐type doping, respectively, there are good reasons to believe that these host:guest compounds might function as the electroactive compound in LEC devices.…”

Recent Progress of Fiber Shaped Lighting Devices for Smart Display Applications—A Fibertronic Perspective

“…The research field of the LEC devices has been mainly classified by these two primary light‐emitting materials. For a detailed overview of LEC devices, the reader is referred to previously published review articles . In the following, we will briefly introduce the emission mechanism and properties of LECs and highlight some recent progress related to fiber‐based LEC devices.…”

“…i) Photographs of an operating stretchable fabric‐based PLEC. a) Reproduced with permission . Copyright 2016, Springer International Publishing Switzerland.…”