25 Years of Light‐Emitting Electrochemical Cells: A Flexible and Stretchable Perspective. Issue 21 (14th April 2021)

• Record Type: Journal Article
• Authors: Schlingman, Kory; Chen, Yiting; Carmichael, R. Stephen; Carmichael, Tricia Breen
• Is Part Of: Advanced materials. Volume 33:Issue 21(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-04-14
• Subjects: electroluminescence -- flexible electronics -- light‐emitting electrochemical cells -- printed electronics -- stretchable electronics; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202006863
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Light‐emitting electrochemical cells (LECs) are simple electroluminescent devices comprising an emissive material containing mobile ions sandwiched between two electrodes. The operating mechanism of the LEC involves both ionic and electronic transport, distinguishing it from its more well‐known cousin, the organic light‐emitting diode (OLED). While OLEDs have become a leading player in commercial displays, LECs have flourished in academic research due to the simple device architecture and unique features of its operating mechanism, inviting exploration of new materials and fabrication strategies. These explorations have brought LECs to an exciting frontier in advanced optoelectronics: flexible and stretchable light‐emitting devices. Flexible and stretchable LECs are discussed herein, presenting the LEC system as a robust and fault‐tolerant development platform. The engineering of emissive composites is highlighted to control mechanical properties, and how the tolerance of LECs to electrode work function and roughness has enabled the incorporation of new electrode materials to achieve flexibility and stretchability. As part of this story, the solution processability of LECs has led to exciting demonstrations of flexible and printed LECs. An outlook is provided for LECs that builds on these strengths, potentially leading to flexible, stretchable, low‐cost devices such as illuminated tags, smart packaging, flexible signage, and wearable illumination. Abstract : For 25 years, the unique structural and operating properties of light‐emitting electrochemical cells (LECs) have invited creative research exploration. A discussion of how the LEC became a robust and fault‐tolerant platform for mechanically flexible and stretchable devices through the integration of new emissive and electrode materials is presented. Printing fabrication methods, vital for the commercialization of flexible LECs, are also discussed.